diff --git a/Bootloaders/CDC/makefile b/Bootloaders/CDC/makefile
index 92b63dad3c81ea416b68b326470a23771facd0ec..cdde8d2b95e9a3b1f53e7cc5ba160fe35417844f 100644
--- a/Bootloaders/CDC/makefile
+++ b/Bootloaders/CDC/makefile
@@ -67,8 +67,8 @@ BOARD = USBKEY
 #     calculate timings. Do NOT tack on a 'UL' at the end, this will be done
 #     automatically to create a 32-bit value in your source code.
 #
-#     This will be an integer division of F_CLOCK below, as it is sourced by
-#     F_CLOCK after it has run through any CPU prescalers. Note that this value
+#     This will be an integer division of F_USB below, as it is sourced by
+#     F_USB after it has run through any CPU prescalers. Note that this value
 #     does not *change* the processor frequency - it should merely be updated to
 #     reflect the processor speed set externally so that the code can use accurate
 #     software delays.
@@ -76,7 +76,7 @@ F_CPU = 8000000
 
 
 # Input clock frequency.
-#     This will define a symbol, F_CLOCK, in all source code files equal to the
+#     This will define a symbol, F_USB, in all source code files equal to the
 #     input clock frequency (before any prescaling is performed) in Hz. This value may
 #     differ from F_CPU if prescaling is used on the latter, and is required as the
 #     raw input clock is fed directly to the PLL sections of the AVR for high speed
@@ -86,7 +86,7 @@ F_CPU = 8000000
 #
 #     If no clock division is performed on the input clock inside the AVR (via the
 #     CPU clock adjust registers or the clock division fuses), this will be equal to F_CPU.
-F_CLOCK = $(F_CPU)
+F_USB = $(F_CPU)
 
 
 # Starting byte address of the bootloader, as a byte address - computed via the formula
@@ -190,7 +190,7 @@ CSTANDARD = -std=c99
 
 # Place -D or -U options here for C sources
 CDEFS  = -DF_CPU=$(F_CPU)UL
-CDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CDEFS += -DF_USB=$(F_USB)UL
 CDEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 CDEFS += -DBOOT_START_ADDR=$(BOOT_START)UL
 CDEFS += $(LUFA_OPTS)
@@ -198,7 +198,7 @@ CDEFS += $(LUFA_OPTS)
 
 # Place -D or -U options here for ASM sources
 ADEFS  = -DF_CPU=$(F_CPU)
-ADEFS += -DF_CLOCK=$(F_CLOCK)UL
+ADEFS += -DF_USB=$(F_USB)UL
 ADEFS += -DBOARD=BOARD_$(BOARD)
 ADEFS += -DBOOT_START_ADDR=$(BOOT_START)UL
 ADEFS += $(LUFA_OPTS)
@@ -206,7 +206,7 @@ ADEFS += $(LUFA_OPTS)
 
 # Place -D or -U options here for C++ sources
 CPPDEFS  = -DF_CPU=$(F_CPU)UL
-CPPDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CPPDEFS += -DF_USB=$(F_USB)UL
 CPPDEFS += -DBOARD=BOARD_$(BOARD)
 CPPDEFS += -DBOOT_START_ADDR=$(BOOT_START)UL
 CPPDEFS += $(LUFA_OPTS)
diff --git a/Bootloaders/DFU/makefile b/Bootloaders/DFU/makefile
index d77933b6bbbe07102484ff0d0048fdea4a696534..458a6ce869cb4794fcb07f937f507df80dda03b4 100644
--- a/Bootloaders/DFU/makefile
+++ b/Bootloaders/DFU/makefile
@@ -67,8 +67,8 @@ BOARD = USBKEY
 #     calculate timings. Do NOT tack on a 'UL' at the end, this will be done
 #     automatically to create a 32-bit value in your source code.
 #
-#     This will be an integer division of F_CLOCK below, as it is sourced by
-#     F_CLOCK after it has run through any CPU prescalers. Note that this value
+#     This will be an integer division of F_USB below, as it is sourced by
+#     F_USB after it has run through any CPU prescalers. Note that this value
 #     does not *change* the processor frequency - it should merely be updated to
 #     reflect the processor speed set externally so that the code can use accurate
 #     software delays.
@@ -76,7 +76,7 @@ F_CPU = 8000000
 
 
 # Input clock frequency.
-#     This will define a symbol, F_CLOCK, in all source code files equal to the
+#     This will define a symbol, F_USB, in all source code files equal to the
 #     input clock frequency (before any prescaling is performed) in Hz. This value may
 #     differ from F_CPU if prescaling is used on the latter, and is required as the
 #     raw input clock is fed directly to the PLL sections of the AVR for high speed
@@ -86,7 +86,7 @@ F_CPU = 8000000
 #
 #     If no clock division is performed on the input clock inside the AVR (via the
 #     CPU clock adjust registers or the clock division fuses), this will be equal to F_CPU.
-F_CLOCK = $(F_CPU)
+F_USB = $(F_CPU)
 
 
 # Starting byte address of the bootloader, as a byte address - computed via the formula
@@ -185,7 +185,7 @@ CSTANDARD = -std=c99
 
 # Place -D or -U options here for C sources
 CDEFS  = -DF_CPU=$(F_CPU)UL
-CDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CDEFS += -DF_USB=$(F_USB)UL
 CDEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 CDEFS += -DBOOT_START_ADDR=$(BOOT_START)UL
 CDEFS += $(LUFA_OPTS)
@@ -193,7 +193,7 @@ CDEFS += $(LUFA_OPTS)
 
 # Place -D or -U options here for ASM sources
 ADEFS  = -DF_CPU=$(F_CPU)
-ADEFS += -DF_CLOCK=$(F_CLOCK)UL
+ADEFS += -DF_USB=$(F_USB)UL
 ADEFS += -DBOARD=BOARD_$(BOARD)
 ADEFS += -DBOOT_START_ADDR=$(BOOT_START)UL
 ADEFS += $(LUFA_OPTS)
@@ -201,7 +201,7 @@ ADEFS += $(LUFA_OPTS)
 
 # Place -D or -U options here for C++ sources
 CPPDEFS  = -DF_CPU=$(F_CPU)UL
-CPPDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CPPDEFS += -DF_USB=$(F_USB)UL
 CPPDEFS += -DBOARD=BOARD_$(BOARD)
 CPPDEFS += -DBOOT_START_ADDR=$(BOOT_START)UL
 CPPDEFS += $(LUFA_OPTS)
diff --git a/Bootloaders/HID/makefile b/Bootloaders/HID/makefile
index 6d8fbf560b7a6f66aab72f60b340e41760233308..738ecc6383c90e3a7a9c5f05ebfc61e3534d1c35 100644
--- a/Bootloaders/HID/makefile
+++ b/Bootloaders/HID/makefile
@@ -67,8 +67,8 @@ BOARD = USBKEY
 #     calculate timings. Do NOT tack on a 'UL' at the end, this will be done
 #     automatically to create a 32-bit value in your source code.
 #
-#     This will be an integer division of F_CLOCK below, as it is sourced by
-#     F_CLOCK after it has run through any CPU prescalers. Note that this value
+#     This will be an integer division of F_USB below, as it is sourced by
+#     F_USB after it has run through any CPU prescalers. Note that this value
 #     does not *change* the processor frequency - it should merely be updated to
 #     reflect the processor speed set externally so that the code can use accurate
 #     software delays.
@@ -76,7 +76,7 @@ F_CPU = 8000000
 
 
 # Input clock frequency.
-#     This will define a symbol, F_CLOCK, in all source code files equal to the
+#     This will define a symbol, F_USB, in all source code files equal to the
 #     input clock frequency (before any prescaling is performed) in Hz. This value may
 #     differ from F_CPU if prescaling is used on the latter, and is required as the
 #     raw input clock is fed directly to the PLL sections of the AVR for high speed
@@ -86,7 +86,7 @@ F_CPU = 8000000
 #
 #     If no clock division is performed on the input clock inside the AVR (via the
 #     CPU clock adjust registers or the clock division fuses), this will be equal to F_CPU.
-F_CLOCK = $(F_CPU)
+F_USB = $(F_CPU)
 
 
 # Starting byte address of the bootloader, as a byte address - computed via the formula
@@ -185,7 +185,7 @@ CSTANDARD = -std=c99
 
 # Place -D or -U options here for C sources
 CDEFS  = -DF_CPU=$(F_CPU)UL
-CDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CDEFS += -DF_USB=$(F_USB)UL
 CDEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 CDEFS += -DBOOT_START_ADDR=$(BOOT_START)UL
 CDEFS += $(LUFA_OPTS)
@@ -193,7 +193,7 @@ CDEFS += $(LUFA_OPTS)
 
 # Place -D or -U options here for ASM sources
 ADEFS  = -DF_CPU=$(F_CPU)
-ADEFS += -DF_CLOCK=$(F_CLOCK)UL
+ADEFS += -DF_USB=$(F_USB)UL
 ADEFS += -DBOARD=BOARD_$(BOARD)
 ADEFS += -DBOOT_START_ADDR=$(BOOT_START)UL
 ADEFS += $(LUFA_OPTS)
@@ -201,7 +201,7 @@ ADEFS += $(LUFA_OPTS)
 
 # Place -D or -U options here for C++ sources
 CPPDEFS  = -DF_CPU=$(F_CPU)UL
-CPPDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CPPDEFS += -DF_USB=$(F_USB)UL
 CPPDEFS += -DBOARD=BOARD_$(BOARD)
 CPPDEFS += -DBOOT_START_ADDR=$(BOOT_START)UL
 CPPDEFS += $(LUFA_OPTS)
diff --git a/Demos/Device/ClassDriver/AudioInput/makefile b/Demos/Device/ClassDriver/AudioInput/makefile
index 371375567be982a9e25654d0c200ed71615a7e1a..969aa904e74628a73650549e1164b90dc5a50746 100644
--- a/Demos/Device/ClassDriver/AudioInput/makefile
+++ b/Demos/Device/ClassDriver/AudioInput/makefile
@@ -79,8 +79,8 @@ BOARD = USBKEY
 #     calculate timings. Do NOT tack on a 'UL' at the end, this will be done
 #     automatically to create a 32-bit value in your source code.
 #
-#     This will be an integer division of F_CLOCK below, as it is sourced by
-#     F_CLOCK after it has run through any CPU prescalers. Note that this value
+#     This will be an integer division of F_USB below, as it is sourced by
+#     F_USB after it has run through any CPU prescalers. Note that this value
 #     does not *change* the processor frequency - it should merely be updated to
 #     reflect the processor speed set externally so that the code can use accurate
 #     software delays.
@@ -88,7 +88,7 @@ F_CPU = 8000000
 
 
 # Input clock frequency.
-#     This will define a symbol, F_CLOCK, in all source code files equal to the
+#     This will define a symbol, F_USB, in all source code files equal to the
 #     input clock frequency (before any prescaling is performed) in Hz. This value may
 #     differ from F_CPU if prescaling is used on the latter, and is required as the
 #     raw input clock is fed directly to the PLL sections of the AVR for high speed
@@ -98,7 +98,7 @@ F_CPU = 8000000
 #
 #     If no clock division is performed on the input clock inside the AVR (via the
 #     CPU clock adjust registers or the clock division fuses), this will be equal to F_CPU.
-F_CLOCK = $(F_CPU)
+F_USB = $(F_CPU)
 
 
 # Output format. (can be srec, ihex, binary)
@@ -185,20 +185,20 @@ CSTANDARD = -std=c99
 
 # Place -D or -U options here for C sources
 CDEFS  = -DF_CPU=$(F_CPU)UL
-CDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CDEFS += -DF_USB=$(F_USB)UL
 CDEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 CDEFS += $(LUFA_OPTS)
 
 
 # Place -D or -U options here for ASM sources
 ADEFS  = -DF_CPU=$(F_CPU)
-ADEFS += -DF_CLOCK=$(F_CLOCK)UL
+ADEFS += -DF_USB=$(F_USB)UL
 ADEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 ADEFS += $(LUFA_OPTS)
 
 # Place -D or -U options here for C++ sources
 CPPDEFS  = -DF_CPU=$(F_CPU)UL
-CPPDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CPPDEFS += -DF_USB=$(F_USB)UL
 CPPDEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 CPPDEFS += $(LUFA_OPTS)
 #CPPDEFS += -D__STDC_LIMIT_MACROS
diff --git a/Demos/Device/ClassDriver/AudioOutput/makefile b/Demos/Device/ClassDriver/AudioOutput/makefile
index 2f23514eaefd908cdbf8d58b7e5dd41f8e3a8d47..dce868a965457f5389884396ddd9134f60881b3d 100644
--- a/Demos/Device/ClassDriver/AudioOutput/makefile
+++ b/Demos/Device/ClassDriver/AudioOutput/makefile
@@ -79,8 +79,8 @@ BOARD = USBKEY
 #     calculate timings. Do NOT tack on a 'UL' at the end, this will be done
 #     automatically to create a 32-bit value in your source code.
 #
-#     This will be an integer division of F_CLOCK below, as it is sourced by
-#     F_CLOCK after it has run through any CPU prescalers. Note that this value
+#     This will be an integer division of F_USB below, as it is sourced by
+#     F_USB after it has run through any CPU prescalers. Note that this value
 #     does not *change* the processor frequency - it should merely be updated to
 #     reflect the processor speed set externally so that the code can use accurate
 #     software delays.
@@ -88,7 +88,7 @@ F_CPU = 8000000
 
 
 # Input clock frequency.
-#     This will define a symbol, F_CLOCK, in all source code files equal to the
+#     This will define a symbol, F_USB, in all source code files equal to the
 #     input clock frequency (before any prescaling is performed) in Hz. This value may
 #     differ from F_CPU if prescaling is used on the latter, and is required as the
 #     raw input clock is fed directly to the PLL sections of the AVR for high speed
@@ -98,7 +98,7 @@ F_CPU = 8000000
 #
 #     If no clock division is performed on the input clock inside the AVR (via the
 #     CPU clock adjust registers or the clock division fuses), this will be equal to F_CPU.
-F_CLOCK = $(F_CPU)
+F_USB = $(F_CPU)
 
 
 # Output format. (can be srec, ihex, binary)
@@ -186,20 +186,20 @@ CSTANDARD = -std=c99
 
 # Place -D or -U options here for C sources
 CDEFS  = -DF_CPU=$(F_CPU)UL
-CDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CDEFS += -DF_USB=$(F_USB)UL
 CDEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 CDEFS += $(LUFA_OPTS)
 
 
 # Place -D or -U options here for ASM sources
 ADEFS  = -DF_CPU=$(F_CPU)
-ADEFS += -DF_CLOCK=$(F_CLOCK)UL
+ADEFS += -DF_USB=$(F_USB)UL
 ADEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 ADEFS += $(LUFA_OPTS)
 
 # Place -D or -U options here for C++ sources
 CPPDEFS  = -DF_CPU=$(F_CPU)UL
-CPPDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CPPDEFS += -DF_USB=$(F_USB)UL
 CPPDEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 CPPDEFS += $(LUFA_OPTS)
 #CPPDEFS += -D__STDC_LIMIT_MACROS
diff --git a/Demos/Device/ClassDriver/DualVirtualSerial/makefile b/Demos/Device/ClassDriver/DualVirtualSerial/makefile
index 9234fe9e6e6b941a58fba001d7f3f58b57ad6c70..75d9bed97fc81c4b66edc35cd824a8c6c2ae061f 100644
--- a/Demos/Device/ClassDriver/DualVirtualSerial/makefile
+++ b/Demos/Device/ClassDriver/DualVirtualSerial/makefile
@@ -79,8 +79,8 @@ BOARD = USBKEY
 #     calculate timings. Do NOT tack on a 'UL' at the end, this will be done
 #     automatically to create a 32-bit value in your source code.
 #
-#     This will be an integer division of F_CLOCK below, as it is sourced by
-#     F_CLOCK after it has run through any CPU prescalers. Note that this value
+#     This will be an integer division of F_USB below, as it is sourced by
+#     F_USB after it has run through any CPU prescalers. Note that this value
 #     does not *change* the processor frequency - it should merely be updated to
 #     reflect the processor speed set externally so that the code can use accurate
 #     software delays.
@@ -88,7 +88,7 @@ F_CPU = 8000000
 
 
 # Input clock frequency.
-#     This will define a symbol, F_CLOCK, in all source code files equal to the
+#     This will define a symbol, F_USB, in all source code files equal to the
 #     input clock frequency (before any prescaling is performed) in Hz. This value may
 #     differ from F_CPU if prescaling is used on the latter, and is required as the
 #     raw input clock is fed directly to the PLL sections of the AVR for high speed
@@ -98,7 +98,7 @@ F_CPU = 8000000
 #
 #     If no clock division is performed on the input clock inside the AVR (via the
 #     CPU clock adjust registers or the clock division fuses), this will be equal to F_CPU.
-F_CLOCK = $(F_CPU)
+F_USB = $(F_CPU)
 
 
 # Output format. (can be srec, ihex, binary)
@@ -182,20 +182,20 @@ CSTANDARD = -std=c99
 
 # Place -D or -U options here for C sources
 CDEFS  = -DF_CPU=$(F_CPU)UL
-CDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CDEFS += -DF_USB=$(F_USB)UL
 CDEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 CDEFS += $(LUFA_OPTS)
 
 
 # Place -D or -U options here for ASM sources
 ADEFS  = -DF_CPU=$(F_CPU)
-ADEFS += -DF_CLOCK=$(F_CLOCK)UL
+ADEFS += -DF_USB=$(F_USB)UL
 ADEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 ADEFS += $(LUFA_OPTS)
 
 # Place -D or -U options here for C++ sources
 CPPDEFS  = -DF_CPU=$(F_CPU)UL
-CPPDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CPPDEFS += -DF_USB=$(F_USB)UL
 CPPDEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 CPPDEFS += $(LUFA_OPTS)
 #CPPDEFS += -D__STDC_LIMIT_MACROS
diff --git a/Demos/Device/ClassDriver/GenericHID/makefile b/Demos/Device/ClassDriver/GenericHID/makefile
index b20d045d9ddcac406d09c37befed17e7db08c914..d015b23fc2349b0a446e030b8d2069e5823a5e62 100644
--- a/Demos/Device/ClassDriver/GenericHID/makefile
+++ b/Demos/Device/ClassDriver/GenericHID/makefile
@@ -79,8 +79,8 @@ BOARD = USBKEY
 #     calculate timings. Do NOT tack on a 'UL' at the end, this will be done
 #     automatically to create a 32-bit value in your source code.
 #
-#     This will be an integer division of F_CLOCK below, as it is sourced by
-#     F_CLOCK after it has run through any CPU prescalers. Note that this value
+#     This will be an integer division of F_USB below, as it is sourced by
+#     F_USB after it has run through any CPU prescalers. Note that this value
 #     does not *change* the processor frequency - it should merely be updated to
 #     reflect the processor speed set externally so that the code can use accurate
 #     software delays.
@@ -88,7 +88,7 @@ F_CPU = 8000000
 
 
 # Input clock frequency.
-#     This will define a symbol, F_CLOCK, in all source code files equal to the
+#     This will define a symbol, F_USB, in all source code files equal to the
 #     input clock frequency (before any prescaling is performed) in Hz. This value may
 #     differ from F_CPU if prescaling is used on the latter, and is required as the
 #     raw input clock is fed directly to the PLL sections of the AVR for high speed
@@ -98,7 +98,7 @@ F_CPU = 8000000
 #
 #     If no clock division is performed on the input clock inside the AVR (via the
 #     CPU clock adjust registers or the clock division fuses), this will be equal to F_CPU.
-F_CLOCK = $(F_CPU)
+F_USB = $(F_CPU)
 
 
 # Output format. (can be srec, ihex, binary)
@@ -182,20 +182,20 @@ CSTANDARD = -std=c99
 
 # Place -D or -U options here for C sources
 CDEFS  = -DF_CPU=$(F_CPU)UL
-CDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CDEFS += -DF_USB=$(F_USB)UL
 CDEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 CDEFS += $(LUFA_OPTS)
 
 
 # Place -D or -U options here for ASM sources
 ADEFS  = -DF_CPU=$(F_CPU)
-ADEFS += -DF_CLOCK=$(F_CLOCK)UL
+ADEFS += -DF_USB=$(F_USB)UL
 ADEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 ADEFS += $(LUFA_OPTS)
 
 # Place -D or -U options here for C++ sources
 CPPDEFS  = -DF_CPU=$(F_CPU)UL
-CPPDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CPPDEFS += -DF_USB=$(F_USB)UL
 CPPDEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 CPPDEFS += $(LUFA_OPTS)
 #CPPDEFS += -D__STDC_LIMIT_MACROS
diff --git a/Demos/Device/ClassDriver/Joystick/makefile b/Demos/Device/ClassDriver/Joystick/makefile
index 23845f4b52dbd2164771f1cf76fd87571f919ce9..0ec41198c0a2a82dbef49ce9360c73af3321a113 100644
--- a/Demos/Device/ClassDriver/Joystick/makefile
+++ b/Demos/Device/ClassDriver/Joystick/makefile
@@ -79,8 +79,8 @@ BOARD = USBKEY
 #     calculate timings. Do NOT tack on a 'UL' at the end, this will be done
 #     automatically to create a 32-bit value in your source code.
 #
-#     This will be an integer division of F_CLOCK below, as it is sourced by
-#     F_CLOCK after it has run through any CPU prescalers. Note that this value
+#     This will be an integer division of F_USB below, as it is sourced by
+#     F_USB after it has run through any CPU prescalers. Note that this value
 #     does not *change* the processor frequency - it should merely be updated to
 #     reflect the processor speed set externally so that the code can use accurate
 #     software delays.
@@ -88,7 +88,7 @@ F_CPU = 8000000
 
 
 # Input clock frequency.
-#     This will define a symbol, F_CLOCK, in all source code files equal to the
+#     This will define a symbol, F_USB, in all source code files equal to the
 #     input clock frequency (before any prescaling is performed) in Hz. This value may
 #     differ from F_CPU if prescaling is used on the latter, and is required as the
 #     raw input clock is fed directly to the PLL sections of the AVR for high speed
@@ -98,7 +98,7 @@ F_CPU = 8000000
 #
 #     If no clock division is performed on the input clock inside the AVR (via the
 #     CPU clock adjust registers or the clock division fuses), this will be equal to F_CPU.
-F_CLOCK = $(F_CPU)
+F_USB = $(F_CPU)
 
 
 # Output format. (can be srec, ihex, binary)
@@ -182,20 +182,20 @@ CSTANDARD = -std=c99
 
 # Place -D or -U options here for C sources
 CDEFS  = -DF_CPU=$(F_CPU)UL
-CDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CDEFS += -DF_USB=$(F_USB)UL
 CDEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 CDEFS += $(LUFA_OPTS)
 
 
 # Place -D or -U options here for ASM sources
 ADEFS  = -DF_CPU=$(F_CPU)
-ADEFS += -DF_CLOCK=$(F_CLOCK)UL
+ADEFS += -DF_USB=$(F_USB)UL
 ADEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 ADEFS += $(LUFA_OPTS)
 
 # Place -D or -U options here for C++ sources
 CPPDEFS  = -DF_CPU=$(F_CPU)UL
-CPPDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CPPDEFS += -DF_USB=$(F_USB)UL
 CPPDEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 CPPDEFS += $(LUFA_OPTS)
 #CPPDEFS += -D__STDC_LIMIT_MACROS
diff --git a/Demos/Device/ClassDriver/Keyboard/makefile b/Demos/Device/ClassDriver/Keyboard/makefile
index 7981b5d034266c4150751bbbc14b047c8ae6efad..31236f0347e61585a585da7c96a23476e30a950a 100644
--- a/Demos/Device/ClassDriver/Keyboard/makefile
+++ b/Demos/Device/ClassDriver/Keyboard/makefile
@@ -79,8 +79,8 @@ BOARD = USBKEY
 #     calculate timings. Do NOT tack on a 'UL' at the end, this will be done
 #     automatically to create a 32-bit value in your source code.
 #
-#     This will be an integer division of F_CLOCK below, as it is sourced by
-#     F_CLOCK after it has run through any CPU prescalers. Note that this value
+#     This will be an integer division of F_USB below, as it is sourced by
+#     F_USB after it has run through any CPU prescalers. Note that this value
 #     does not *change* the processor frequency - it should merely be updated to
 #     reflect the processor speed set externally so that the code can use accurate
 #     software delays.
@@ -88,7 +88,7 @@ F_CPU = 8000000
 
 
 # Input clock frequency.
-#     This will define a symbol, F_CLOCK, in all source code files equal to the
+#     This will define a symbol, F_USB, in all source code files equal to the
 #     input clock frequency (before any prescaling is performed) in Hz. This value may
 #     differ from F_CPU if prescaling is used on the latter, and is required as the
 #     raw input clock is fed directly to the PLL sections of the AVR for high speed
@@ -98,7 +98,7 @@ F_CPU = 8000000
 #
 #     If no clock division is performed on the input clock inside the AVR (via the
 #     CPU clock adjust registers or the clock division fuses), this will be equal to F_CPU.
-F_CLOCK = $(F_CPU)
+F_USB = $(F_CPU)
 
 
 # Output format. (can be srec, ihex, binary)
@@ -182,20 +182,20 @@ CSTANDARD = -std=c99
 
 # Place -D or -U options here for C sources
 CDEFS  = -DF_CPU=$(F_CPU)UL
-CDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CDEFS += -DF_USB=$(F_USB)UL
 CDEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 CDEFS += $(LUFA_OPTS)
 
 
 # Place -D or -U options here for ASM sources
 ADEFS  = -DF_CPU=$(F_CPU)
-ADEFS += -DF_CLOCK=$(F_CLOCK)UL
+ADEFS += -DF_USB=$(F_USB)UL
 ADEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 ADEFS += $(LUFA_OPTS)
 
 # Place -D or -U options here for C++ sources
 CPPDEFS  = -DF_CPU=$(F_CPU)UL
-CPPDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CPPDEFS += -DF_USB=$(F_USB)UL
 CPPDEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 CPPDEFS += $(LUFA_OPTS)
 #CPPDEFS += -D__STDC_LIMIT_MACROS
diff --git a/Demos/Device/ClassDriver/KeyboardMouse/makefile b/Demos/Device/ClassDriver/KeyboardMouse/makefile
index c4477dc00f5210444ee708f2985228fda40b1d2d..bc2d6914aaa3b94b1fd662d1421d3365cdf2e521 100644
--- a/Demos/Device/ClassDriver/KeyboardMouse/makefile
+++ b/Demos/Device/ClassDriver/KeyboardMouse/makefile
@@ -79,8 +79,8 @@ BOARD = USBKEY
 #     calculate timings. Do NOT tack on a 'UL' at the end, this will be done
 #     automatically to create a 32-bit value in your source code.
 #
-#     This will be an integer division of F_CLOCK below, as it is sourced by
-#     F_CLOCK after it has run through any CPU prescalers. Note that this value
+#     This will be an integer division of F_USB below, as it is sourced by
+#     F_USB after it has run through any CPU prescalers. Note that this value
 #     does not *change* the processor frequency - it should merely be updated to
 #     reflect the processor speed set externally so that the code can use accurate
 #     software delays.
@@ -88,7 +88,7 @@ F_CPU = 8000000
 
 
 # Input clock frequency.
-#     This will define a symbol, F_CLOCK, in all source code files equal to the
+#     This will define a symbol, F_USB, in all source code files equal to the
 #     input clock frequency (before any prescaling is performed) in Hz. This value may
 #     differ from F_CPU if prescaling is used on the latter, and is required as the
 #     raw input clock is fed directly to the PLL sections of the AVR for high speed
@@ -98,7 +98,7 @@ F_CPU = 8000000
 #
 #     If no clock division is performed on the input clock inside the AVR (via the
 #     CPU clock adjust registers or the clock division fuses), this will be equal to F_CPU.
-F_CLOCK = $(F_CPU)
+F_USB = $(F_CPU)
 
 
 # Output format. (can be srec, ihex, binary)
@@ -182,20 +182,20 @@ CSTANDARD = -std=c99
 
 # Place -D or -U options here for C sources
 CDEFS  = -DF_CPU=$(F_CPU)UL
-CDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CDEFS += -DF_USB=$(F_USB)UL
 CDEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 CDEFS += $(LUFA_OPTS)
 
 
 # Place -D or -U options here for ASM sources
 ADEFS  = -DF_CPU=$(F_CPU)
-ADEFS += -DF_CLOCK=$(F_CLOCK)UL
+ADEFS += -DF_USB=$(F_USB)UL
 ADEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 ADEFS += $(LUFA_OPTS)
 
 # Place -D or -U options here for C++ sources
 CPPDEFS  = -DF_CPU=$(F_CPU)UL
-CPPDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CPPDEFS += -DF_USB=$(F_USB)UL
 CPPDEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 CPPDEFS += $(LUFA_OPTS)
 #CPPDEFS += -D__STDC_LIMIT_MACROS
diff --git a/Demos/Device/ClassDriver/KeyboardMouseMultiReport/makefile b/Demos/Device/ClassDriver/KeyboardMouseMultiReport/makefile
index 9fcd9aeae316951b5b7e50836e9f7bf4b89da3be..317d26db1b5d199d0cf578bab536b97183fb9980 100644
--- a/Demos/Device/ClassDriver/KeyboardMouseMultiReport/makefile
+++ b/Demos/Device/ClassDriver/KeyboardMouseMultiReport/makefile
@@ -79,8 +79,8 @@ BOARD = USBKEY
 #     calculate timings. Do NOT tack on a 'UL' at the end, this will be done
 #     automatically to create a 32-bit value in your source code.
 #
-#     This will be an integer division of F_CLOCK below, as it is sourced by
-#     F_CLOCK after it has run through any CPU prescalers. Note that this value
+#     This will be an integer division of F_USB below, as it is sourced by
+#     F_USB after it has run through any CPU prescalers. Note that this value
 #     does not *change* the processor frequency - it should merely be updated to
 #     reflect the processor speed set externally so that the code can use accurate
 #     software delays.
@@ -88,7 +88,7 @@ F_CPU = 8000000
 
 
 # Input clock frequency.
-#     This will define a symbol, F_CLOCK, in all source code files equal to the
+#     This will define a symbol, F_USB, in all source code files equal to the
 #     input clock frequency (before any prescaling is performed) in Hz. This value may
 #     differ from F_CPU if prescaling is used on the latter, and is required as the
 #     raw input clock is fed directly to the PLL sections of the AVR for high speed
@@ -98,7 +98,7 @@ F_CPU = 8000000
 #
 #     If no clock division is performed on the input clock inside the AVR (via the
 #     CPU clock adjust registers or the clock division fuses), this will be equal to F_CPU.
-F_CLOCK = $(F_CPU)
+F_USB = $(F_CPU)
 
 
 # Output format. (can be srec, ihex, binary)
@@ -182,20 +182,20 @@ CSTANDARD = -std=c99
 
 # Place -D or -U options here for C sources
 CDEFS  = -DF_CPU=$(F_CPU)UL
-CDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CDEFS += -DF_USB=$(F_USB)UL
 CDEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 CDEFS += $(LUFA_OPTS)
 
 
 # Place -D or -U options here for ASM sources
 ADEFS  = -DF_CPU=$(F_CPU)
-ADEFS += -DF_CLOCK=$(F_CLOCK)UL
+ADEFS += -DF_USB=$(F_USB)UL
 ADEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 ADEFS += $(LUFA_OPTS)
 
 # Place -D or -U options here for C++ sources
 CPPDEFS  = -DF_CPU=$(F_CPU)UL
-CPPDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CPPDEFS += -DF_USB=$(F_USB)UL
 CPPDEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 CPPDEFS += $(LUFA_OPTS)
 #CPPDEFS += -D__STDC_LIMIT_MACROS
diff --git a/Demos/Device/ClassDriver/MIDI/makefile b/Demos/Device/ClassDriver/MIDI/makefile
index 11b76deb4a5255abc2113193e7dcfd75d2aafd9d..945d992038e07cff96da7748221b296ead1618df 100644
--- a/Demos/Device/ClassDriver/MIDI/makefile
+++ b/Demos/Device/ClassDriver/MIDI/makefile
@@ -79,8 +79,8 @@ BOARD = USBKEY
 #     calculate timings. Do NOT tack on a 'UL' at the end, this will be done
 #     automatically to create a 32-bit value in your source code.
 #
-#     This will be an integer division of F_CLOCK below, as it is sourced by
-#     F_CLOCK after it has run through any CPU prescalers. Note that this value
+#     This will be an integer division of F_USB below, as it is sourced by
+#     F_USB after it has run through any CPU prescalers. Note that this value
 #     does not *change* the processor frequency - it should merely be updated to
 #     reflect the processor speed set externally so that the code can use accurate
 #     software delays.
@@ -88,7 +88,7 @@ F_CPU = 8000000
 
 
 # Input clock frequency.
-#     This will define a symbol, F_CLOCK, in all source code files equal to the
+#     This will define a symbol, F_USB, in all source code files equal to the
 #     input clock frequency (before any prescaling is performed) in Hz. This value may
 #     differ from F_CPU if prescaling is used on the latter, and is required as the
 #     raw input clock is fed directly to the PLL sections of the AVR for high speed
@@ -98,7 +98,7 @@ F_CPU = 8000000
 #
 #     If no clock division is performed on the input clock inside the AVR (via the
 #     CPU clock adjust registers or the clock division fuses), this will be equal to F_CPU.
-F_CLOCK = $(F_CPU)
+F_USB = $(F_CPU)
 
 
 # Output format. (can be srec, ihex, binary)
@@ -182,20 +182,20 @@ CSTANDARD = -std=c99
 
 # Place -D or -U options here for C sources
 CDEFS  = -DF_CPU=$(F_CPU)UL
-CDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CDEFS += -DF_USB=$(F_USB)UL
 CDEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 CDEFS += $(LUFA_OPTS)
 
 
 # Place -D or -U options here for ASM sources
 ADEFS  = -DF_CPU=$(F_CPU)
-ADEFS += -DF_CLOCK=$(F_CLOCK)UL
+ADEFS += -DF_USB=$(F_USB)UL
 ADEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 ADEFS += $(LUFA_OPTS)
 
 # Place -D or -U options here for C++ sources
 CPPDEFS  = -DF_CPU=$(F_CPU)UL
-CPPDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CPPDEFS += -DF_USB=$(F_USB)UL
 CPPDEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 CPPDEFS += $(LUFA_OPTS)
 #CPPDEFS += -D__STDC_LIMIT_MACROS
diff --git a/Demos/Device/ClassDriver/MassStorage/makefile b/Demos/Device/ClassDriver/MassStorage/makefile
index bd548f8763e97271434de456414371e1bea8e94a..0e8988fff993940d15a771da008908e54014febe 100644
--- a/Demos/Device/ClassDriver/MassStorage/makefile
+++ b/Demos/Device/ClassDriver/MassStorage/makefile
@@ -79,8 +79,8 @@ BOARD = USBKEY
 #     calculate timings. Do NOT tack on a 'UL' at the end, this will be done
 #     automatically to create a 32-bit value in your source code.
 #
-#     This will be an integer division of F_CLOCK below, as it is sourced by
-#     F_CLOCK after it has run through any CPU prescalers. Note that this value
+#     This will be an integer division of F_USB below, as it is sourced by
+#     F_USB after it has run through any CPU prescalers. Note that this value
 #     does not *change* the processor frequency - it should merely be updated to
 #     reflect the processor speed set externally so that the code can use accurate
 #     software delays.
@@ -88,7 +88,7 @@ F_CPU = 8000000
 
 
 # Input clock frequency.
-#     This will define a symbol, F_CLOCK, in all source code files equal to the
+#     This will define a symbol, F_USB, in all source code files equal to the
 #     input clock frequency (before any prescaling is performed) in Hz. This value may
 #     differ from F_CPU if prescaling is used on the latter, and is required as the
 #     raw input clock is fed directly to the PLL sections of the AVR for high speed
@@ -98,7 +98,7 @@ F_CPU = 8000000
 #
 #     If no clock division is performed on the input clock inside the AVR (via the
 #     CPU clock adjust registers or the clock division fuses), this will be equal to F_CPU.
-F_CLOCK = $(F_CPU)
+F_USB = $(F_CPU)
 
 
 # Output format. (can be srec, ihex, binary)
@@ -185,20 +185,20 @@ CSTANDARD = -std=c99
 
 # Place -D or -U options here for C sources
 CDEFS  = -DF_CPU=$(F_CPU)UL
-CDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CDEFS += -DF_USB=$(F_USB)UL
 CDEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 CDEFS += $(LUFA_OPTS)
 
 
 # Place -D or -U options here for ASM sources
 ADEFS  = -DF_CPU=$(F_CPU)
-ADEFS += -DF_CLOCK=$(F_CLOCK)UL
+ADEFS += -DF_USB=$(F_USB)UL
 ADEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 ADEFS += $(LUFA_OPTS)
 
 # Place -D or -U options here for C++ sources
 CPPDEFS  = -DF_CPU=$(F_CPU)UL
-CPPDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CPPDEFS += -DF_USB=$(F_USB)UL
 CPPDEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 CPPDEFS += $(LUFA_OPTS)
 #CPPDEFS += -D__STDC_LIMIT_MACROS
diff --git a/Demos/Device/ClassDriver/MassStorageKeyboard/makefile b/Demos/Device/ClassDriver/MassStorageKeyboard/makefile
index 1d7eaca5388959a82fa14f54493ff664577c0dc8..c044a89fb52e74b90e89be7b80ea9f83ca412560 100644
--- a/Demos/Device/ClassDriver/MassStorageKeyboard/makefile
+++ b/Demos/Device/ClassDriver/MassStorageKeyboard/makefile
@@ -79,8 +79,8 @@ BOARD = USBKEY
 #     calculate timings. Do NOT tack on a 'UL' at the end, this will be done
 #     automatically to create a 32-bit value in your source code.
 #
-#     This will be an integer division of F_CLOCK below, as it is sourced by
-#     F_CLOCK after it has run through any CPU prescalers. Note that this value
+#     This will be an integer division of F_USB below, as it is sourced by
+#     F_USB after it has run through any CPU prescalers. Note that this value
 #     does not *change* the processor frequency - it should merely be updated to
 #     reflect the processor speed set externally so that the code can use accurate
 #     software delays.
@@ -88,7 +88,7 @@ F_CPU = 8000000
 
 
 # Input clock frequency.
-#     This will define a symbol, F_CLOCK, in all source code files equal to the
+#     This will define a symbol, F_USB, in all source code files equal to the
 #     input clock frequency (before any prescaling is performed) in Hz. This value may
 #     differ from F_CPU if prescaling is used on the latter, and is required as the
 #     raw input clock is fed directly to the PLL sections of the AVR for high speed
@@ -98,7 +98,7 @@ F_CPU = 8000000
 #
 #     If no clock division is performed on the input clock inside the AVR (via the
 #     CPU clock adjust registers or the clock division fuses), this will be equal to F_CPU.
-F_CLOCK = $(F_CPU)
+F_USB = $(F_CPU)
 
 
 # Output format. (can be srec, ihex, binary)
@@ -185,20 +185,20 @@ CSTANDARD = -std=c99
 
 # Place -D or -U options here for C sources
 CDEFS  = -DF_CPU=$(F_CPU)UL
-CDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CDEFS += -DF_USB=$(F_USB)UL
 CDEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 CDEFS += $(LUFA_OPTS)
 
 
 # Place -D or -U options here for ASM sources
 ADEFS  = -DF_CPU=$(F_CPU)
-ADEFS += -DF_CLOCK=$(F_CLOCK)UL
+ADEFS += -DF_USB=$(F_USB)UL
 ADEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 ADEFS += $(LUFA_OPTS)
 
 # Place -D or -U options here for C++ sources
 CPPDEFS  = -DF_CPU=$(F_CPU)UL
-CPPDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CPPDEFS += -DF_USB=$(F_USB)UL
 CPPDEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 CPPDEFS += $(LUFA_OPTS)
 #CPPDEFS += -D__STDC_LIMIT_MACROS
diff --git a/Demos/Device/ClassDriver/Mouse/makefile b/Demos/Device/ClassDriver/Mouse/makefile
index 317005f3ae764af42cccc419774960a1c7065d11..792682bf178f123afc024c0930340816cabfbd16 100644
--- a/Demos/Device/ClassDriver/Mouse/makefile
+++ b/Demos/Device/ClassDriver/Mouse/makefile
@@ -79,8 +79,8 @@ BOARD = USBKEY
 #     calculate timings. Do NOT tack on a 'UL' at the end, this will be done
 #     automatically to create a 32-bit value in your source code.
 #
-#     This will be an integer division of F_CLOCK below, as it is sourced by
-#     F_CLOCK after it has run through any CPU prescalers. Note that this value
+#     This will be an integer division of F_USB below, as it is sourced by
+#     F_USB after it has run through any CPU prescalers. Note that this value
 #     does not *change* the processor frequency - it should merely be updated to
 #     reflect the processor speed set externally so that the code can use accurate
 #     software delays.
@@ -88,7 +88,7 @@ F_CPU = 8000000
 
 
 # Input clock frequency.
-#     This will define a symbol, F_CLOCK, in all source code files equal to the
+#     This will define a symbol, F_USB, in all source code files equal to the
 #     input clock frequency (before any prescaling is performed) in Hz. This value may
 #     differ from F_CPU if prescaling is used on the latter, and is required as the
 #     raw input clock is fed directly to the PLL sections of the AVR for high speed
@@ -98,7 +98,7 @@ F_CPU = 8000000
 #
 #     If no clock division is performed on the input clock inside the AVR (via the
 #     CPU clock adjust registers or the clock division fuses), this will be equal to F_CPU.
-F_CLOCK = $(F_CPU)
+F_USB = $(F_CPU)
 
 
 # Output format. (can be srec, ihex, binary)
@@ -182,20 +182,20 @@ CSTANDARD = -std=c99
 
 # Place -D or -U options here for C sources
 CDEFS  = -DF_CPU=$(F_CPU)UL
-CDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CDEFS += -DF_USB=$(F_USB)UL
 CDEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 CDEFS += $(LUFA_OPTS)
 
 
 # Place -D or -U options here for ASM sources
 ADEFS  = -DF_CPU=$(F_CPU)
-ADEFS += -DF_CLOCK=$(F_CLOCK)UL
+ADEFS += -DF_USB=$(F_USB)UL
 ADEFS += -DBOARD=BOARD_$(BOARD)
 ADEFS += $(LUFA_OPTS)
 
 # Place -D or -U options here for C++ sources
 CPPDEFS  = -DF_CPU=$(F_CPU)UL
-CPPDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CPPDEFS += -DF_USB=$(F_USB)UL
 CPPDEFS += -DBOARD=BOARD_$(BOARD)
 CPPDEFS += $(LUFA_OPTS)
 #CPPDEFS += -D__STDC_LIMIT_MACROS
diff --git a/Demos/Device/ClassDriver/RNDISEthernet/makefile b/Demos/Device/ClassDriver/RNDISEthernet/makefile
index 910452b7da912804f4c7a5b37c9b38e97da13799..e3044c8862eeb530c6ac573ecd20f19abe90801d 100644
--- a/Demos/Device/ClassDriver/RNDISEthernet/makefile
+++ b/Demos/Device/ClassDriver/RNDISEthernet/makefile
@@ -79,8 +79,8 @@ BOARD = USBKEY
 #     calculate timings. Do NOT tack on a 'UL' at the end, this will be done
 #     automatically to create a 32-bit value in your source code.
 #
-#     This will be an integer division of F_CLOCK below, as it is sourced by
-#     F_CLOCK after it has run through any CPU prescalers. Note that this value
+#     This will be an integer division of F_USB below, as it is sourced by
+#     F_USB after it has run through any CPU prescalers. Note that this value
 #     does not *change* the processor frequency - it should merely be updated to
 #     reflect the processor speed set externally so that the code can use accurate
 #     software delays.
@@ -88,7 +88,7 @@ F_CPU = 8000000
 
 
 # Input clock frequency.
-#     This will define a symbol, F_CLOCK, in all source code files equal to the
+#     This will define a symbol, F_USB, in all source code files equal to the
 #     input clock frequency (before any prescaling is performed) in Hz. This value may
 #     differ from F_CPU if prescaling is used on the latter, and is required as the
 #     raw input clock is fed directly to the PLL sections of the AVR for high speed
@@ -98,7 +98,7 @@ F_CPU = 8000000
 #
 #     If no clock division is performed on the input clock inside the AVR (via the
 #     CPU clock adjust registers or the clock division fuses), this will be equal to F_CPU.
-F_CLOCK = $(F_CPU)
+F_USB = $(F_CPU)
 
 
 # Output format. (can be srec, ihex, binary)
@@ -200,20 +200,20 @@ CSTANDARD = -std=c99
 
 # Place -D or -U options here for C sources
 CDEFS  = -DF_CPU=$(F_CPU)UL
-CDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CDEFS += -DF_USB=$(F_USB)UL
 CDEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 CDEFS += $(LUFA_OPTS)
 
 
 # Place -D or -U options here for ASM sources
 ADEFS  = -DF_CPU=$(F_CPU)
-ADEFS += -DF_CLOCK=$(F_CLOCK)UL
+ADEFS += -DF_USB=$(F_USB)UL
 ADEFS += -DBOARD=BOARD_$(BOARD)
 ADEFS += $(LUFA_OPTS)
 
 # Place -D or -U options here for C++ sources
 CPPDEFS  = -DF_CPU=$(F_CPU)UL
-CPPDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CPPDEFS += -DF_USB=$(F_USB)UL
 CPPDEFS += -DBOARD=BOARD_$(BOARD)
 CPPDEFS += $(LUFA_OPTS)
 #CPPDEFS += -D__STDC_LIMIT_MACROS
diff --git a/Demos/Device/ClassDriver/VirtualSerial/makefile b/Demos/Device/ClassDriver/VirtualSerial/makefile
index fb7dd779faedbc5a4506c3d4529e0e547ea62727..98d3d72e993456c1a91283eeeae975ba3f4a2d4d 100644
--- a/Demos/Device/ClassDriver/VirtualSerial/makefile
+++ b/Demos/Device/ClassDriver/VirtualSerial/makefile
@@ -79,8 +79,8 @@ BOARD = USBKEY
 #     calculate timings. Do NOT tack on a 'UL' at the end, this will be done
 #     automatically to create a 32-bit value in your source code.
 #
-#     This will be an integer division of F_CLOCK below, as it is sourced by
-#     F_CLOCK after it has run through any CPU prescalers. Note that this value
+#     This will be an integer division of F_USB below, as it is sourced by
+#     F_USB after it has run through any CPU prescalers. Note that this value
 #     does not *change* the processor frequency - it should merely be updated to
 #     reflect the processor speed set externally so that the code can use accurate
 #     software delays.
@@ -88,7 +88,7 @@ F_CPU = 8000000
 
 
 # Input clock frequency.
-#     This will define a symbol, F_CLOCK, in all source code files equal to the
+#     This will define a symbol, F_USB, in all source code files equal to the
 #     input clock frequency (before any prescaling is performed) in Hz. This value may
 #     differ from F_CPU if prescaling is used on the latter, and is required as the
 #     raw input clock is fed directly to the PLL sections of the AVR for high speed
@@ -98,7 +98,7 @@ F_CPU = 8000000
 #
 #     If no clock division is performed on the input clock inside the AVR (via the
 #     CPU clock adjust registers or the clock division fuses), this will be equal to F_CPU.
-F_CLOCK = $(F_CPU)
+F_USB = $(F_CPU)
 
 
 # Output format. (can be srec, ihex, binary)
@@ -182,20 +182,20 @@ CSTANDARD = -std=c99
 
 # Place -D or -U options here for C sources
 CDEFS  = -DF_CPU=$(F_CPU)UL
-CDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CDEFS += -DF_USB=$(F_USB)UL
 CDEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 CDEFS += $(LUFA_OPTS)
 
 
 # Place -D or -U options here for ASM sources
 ADEFS  = -DF_CPU=$(F_CPU)
-ADEFS += -DF_CLOCK=$(F_CLOCK)UL
+ADEFS += -DF_USB=$(F_USB)UL
 ADEFS += -DBOARD=BOARD_$(BOARD)
 ADEFS += $(LUFA_OPTS)
 
 # Place -D or -U options here for C++ sources
 CPPDEFS  = -DF_CPU=$(F_CPU)UL
-CPPDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CPPDEFS += -DF_USB=$(F_USB)UL
 CPPDEFS += -DBOARD=BOARD_$(BOARD)
 CPPDEFS += $(LUFA_OPTS)
 #CPPDEFS += -D__STDC_LIMIT_MACROS
diff --git a/Demos/Device/ClassDriver/VirtualSerialMassStorage/makefile b/Demos/Device/ClassDriver/VirtualSerialMassStorage/makefile
index 658e8db30d863222e36ab50dd16f075548cdc719..a6975183356c87445d9437f27eca93f9ac9fba27 100644
--- a/Demos/Device/ClassDriver/VirtualSerialMassStorage/makefile
+++ b/Demos/Device/ClassDriver/VirtualSerialMassStorage/makefile
@@ -79,8 +79,8 @@ BOARD = USBKEY
 #     calculate timings. Do NOT tack on a 'UL' at the end, this will be done
 #     automatically to create a 32-bit value in your source code.
 #
-#     This will be an integer division of F_CLOCK below, as it is sourced by
-#     F_CLOCK after it has run through any CPU prescalers. Note that this value
+#     This will be an integer division of F_USB below, as it is sourced by
+#     F_USB after it has run through any CPU prescalers. Note that this value
 #     does not *change* the processor frequency - it should merely be updated to
 #     reflect the processor speed set externally so that the code can use accurate
 #     software delays.
@@ -88,7 +88,7 @@ F_CPU = 8000000
 
 
 # Input clock frequency.
-#     This will define a symbol, F_CLOCK, in all source code files equal to the
+#     This will define a symbol, F_USB, in all source code files equal to the
 #     input clock frequency (before any prescaling is performed) in Hz. This value may
 #     differ from F_CPU if prescaling is used on the latter, and is required as the
 #     raw input clock is fed directly to the PLL sections of the AVR for high speed
@@ -98,7 +98,7 @@ F_CPU = 8000000
 #
 #     If no clock division is performed on the input clock inside the AVR (via the
 #     CPU clock adjust registers or the clock division fuses), this will be equal to F_CPU.
-F_CLOCK = $(F_CPU)
+F_USB = $(F_CPU)
 
 
 # Output format. (can be srec, ihex, binary)
@@ -184,20 +184,20 @@ CSTANDARD = -std=c99
 
 # Place -D or -U options here for C sources
 CDEFS  = -DF_CPU=$(F_CPU)UL
-CDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CDEFS += -DF_USB=$(F_USB)UL
 CDEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 CDEFS += $(LUFA_OPTS)
 
 
 # Place -D or -U options here for ASM sources
 ADEFS  = -DF_CPU=$(F_CPU)
-ADEFS += -DF_CLOCK=$(F_CLOCK)UL
+ADEFS += -DF_USB=$(F_USB)UL
 ADEFS += -DBOARD=BOARD_$(BOARD)
 ADEFS += $(LUFA_OPTS)
 
 # Place -D or -U options here for C++ sources
 CPPDEFS  = -DF_CPU=$(F_CPU)UL
-CPPDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CPPDEFS += -DF_USB=$(F_USB)UL
 CPPDEFS += -DBOARD=BOARD_$(BOARD)
 CPPDEFS += $(LUFA_OPTS)
 #CPPDEFS += -D__STDC_LIMIT_MACROS
diff --git a/Demos/Device/ClassDriver/VirtualSerialMouse/makefile b/Demos/Device/ClassDriver/VirtualSerialMouse/makefile
index 2ed7afddf68ce05ae44ee6b988f8f9d446c3b807..a4ed81b565acca5ae3eccfa0d7fd0e95639fac3d 100644
--- a/Demos/Device/ClassDriver/VirtualSerialMouse/makefile
+++ b/Demos/Device/ClassDriver/VirtualSerialMouse/makefile
@@ -79,8 +79,8 @@ BOARD = USBKEY
 #     calculate timings. Do NOT tack on a 'UL' at the end, this will be done
 #     automatically to create a 32-bit value in your source code.
 #
-#     This will be an integer division of F_CLOCK below, as it is sourced by
-#     F_CLOCK after it has run through any CPU prescalers. Note that this value
+#     This will be an integer division of F_USB below, as it is sourced by
+#     F_USB after it has run through any CPU prescalers. Note that this value
 #     does not *change* the processor frequency - it should merely be updated to
 #     reflect the processor speed set externally so that the code can use accurate
 #     software delays.
@@ -88,7 +88,7 @@ F_CPU = 8000000
 
 
 # Input clock frequency.
-#     This will define a symbol, F_CLOCK, in all source code files equal to the
+#     This will define a symbol, F_USB, in all source code files equal to the
 #     input clock frequency (before any prescaling is performed) in Hz. This value may
 #     differ from F_CPU if prescaling is used on the latter, and is required as the
 #     raw input clock is fed directly to the PLL sections of the AVR for high speed
@@ -98,7 +98,7 @@ F_CPU = 8000000
 #
 #     If no clock division is performed on the input clock inside the AVR (via the
 #     CPU clock adjust registers or the clock division fuses), this will be equal to F_CPU.
-F_CLOCK = $(F_CPU)
+F_USB = $(F_CPU)
 
 
 # Output format. (can be srec, ihex, binary)
@@ -182,20 +182,20 @@ CSTANDARD = -std=c99
 
 # Place -D or -U options here for C sources
 CDEFS  = -DF_CPU=$(F_CPU)UL
-CDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CDEFS += -DF_USB=$(F_USB)UL
 CDEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 CDEFS += $(LUFA_OPTS)
 
 
 # Place -D or -U options here for ASM sources
 ADEFS  = -DF_CPU=$(F_CPU)
-ADEFS += -DF_CLOCK=$(F_CLOCK)UL
+ADEFS += -DF_USB=$(F_USB)UL
 ADEFS += -DBOARD=BOARD_$(BOARD)
 ADEFS += $(LUFA_OPTS)
 
 # Place -D or -U options here for C++ sources
 CPPDEFS  = -DF_CPU=$(F_CPU)UL
-CPPDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CPPDEFS += -DF_USB=$(F_USB)UL
 CPPDEFS += -DBOARD=BOARD_$(BOARD)
 CPPDEFS += $(LUFA_OPTS)
 #CPPDEFS += -D__STDC_LIMIT_MACROS
diff --git a/Demos/Device/Incomplete/Sideshow/makefile b/Demos/Device/Incomplete/Sideshow/makefile
index 9439e1d9effa1ea9147ae47a5ed7574666f1aed4..22c5c76dfc519da64468c4da21fc5bc88d2e4d1a 100644
--- a/Demos/Device/Incomplete/Sideshow/makefile
+++ b/Demos/Device/Incomplete/Sideshow/makefile
@@ -79,8 +79,8 @@ BOARD = USBKEY
 #     calculate timings. Do NOT tack on a 'UL' at the end, this will be done
 #     automatically to create a 32-bit value in your source code.
 #
-#     This will be an integer division of F_CLOCK below, as it is sourced by
-#     F_CLOCK after it has run through any CPU prescalers. Note that this value
+#     This will be an integer division of F_USB below, as it is sourced by
+#     F_USB after it has run through any CPU prescalers. Note that this value
 #     does not *change* the processor frequency - it should merely be updated to
 #     reflect the processor speed set externally so that the code can use accurate
 #     software delays.
@@ -88,7 +88,7 @@ F_CPU = 8000000
 
 
 # Input clock frequency.
-#     This will define a symbol, F_CLOCK, in all source code files equal to the
+#     This will define a symbol, F_USB, in all source code files equal to the
 #     input clock frequency (before any prescaling is performed) in Hz. This value may
 #     differ from F_CPU if prescaling is used on the latter, and is required as the
 #     raw input clock is fed directly to the PLL sections of the AVR for high speed
@@ -98,7 +98,7 @@ F_CPU = 8000000
 #
 #     If no clock division is performed on the input clock inside the AVR (via the
 #     CPU clock adjust registers or the clock division fuses), this will be equal to F_CPU.
-F_CLOCK = $(F_CPU)
+F_USB = $(F_CPU)
 
 
 # Output format. (can be srec, ihex, binary)
@@ -186,20 +186,20 @@ CSTANDARD = -std=c99
 
 # Place -D or -U options here for C sources
 CDEFS  = -DF_CPU=$(F_CPU)UL
-CDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CDEFS += -DF_USB=$(F_USB)UL
 CDEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 CDEFS += $(LUFA_OPTS)
 
 
 # Place -D or -U options here for ASM sources
 ADEFS  = -DF_CPU=$(F_CPU)
-ADEFS += -DF_CLOCK=$(F_CLOCK)UL
+ADEFS += -DF_USB=$(F_USB)UL
 ADEFS += -DBOARD=BOARD_$(BOARD)
 ADEFS += $(LUFA_OPTS)
 
 # Place -D or -U options here for C++ sources
 CPPDEFS  = -DF_CPU=$(F_CPU)UL
-CPPDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CPPDEFS += -DF_USB=$(F_USB)UL
 CPPDEFS += -DBOARD=BOARD_$(BOARD)
 CPPDEFS += $(LUFA_OPTS)
 #CPPDEFS += -D__STDC_LIMIT_MACROS
diff --git a/Demos/Device/Incomplete/TestAndMeasurement/makefile b/Demos/Device/Incomplete/TestAndMeasurement/makefile
index 298cd2281c4fb9bb04a507f25e7656e02631ac8a..2f21e102746cddd7f2cdd16457447006bcebab0d 100644
--- a/Demos/Device/Incomplete/TestAndMeasurement/makefile
+++ b/Demos/Device/Incomplete/TestAndMeasurement/makefile
@@ -79,8 +79,8 @@ BOARD = USBKEY
 #     calculate timings. Do NOT tack on a 'UL' at the end, this will be done
 #     automatically to create a 32-bit value in your source code.
 #
-#     This will be an integer division of F_CLOCK below, as it is sourced by
-#     F_CLOCK after it has run through any CPU prescalers. Note that this value
+#     This will be an integer division of F_USB below, as it is sourced by
+#     F_USB after it has run through any CPU prescalers. Note that this value
 #     does not *change* the processor frequency - it should merely be updated to
 #     reflect the processor speed set externally so that the code can use accurate
 #     software delays.
@@ -88,7 +88,7 @@ F_CPU = 8000000
 
 
 # Input clock frequency.
-#     This will define a symbol, F_CLOCK, in all source code files equal to the
+#     This will define a symbol, F_USB, in all source code files equal to the
 #     input clock frequency (before any prescaling is performed) in Hz. This value may
 #     differ from F_CPU if prescaling is used on the latter, and is required as the
 #     raw input clock is fed directly to the PLL sections of the AVR for high speed
@@ -98,7 +98,7 @@ F_CPU = 8000000
 #
 #     If no clock division is performed on the input clock inside the AVR (via the
 #     CPU clock adjust registers or the clock division fuses), this will be equal to F_CPU.
-F_CLOCK = $(F_CPU)
+F_USB = $(F_CPU)
 
 
 # Output format. (can be srec, ihex, binary)
@@ -182,20 +182,20 @@ CSTANDARD = -std=c99
 
 # Place -D or -U options here for C sources
 CDEFS  = -DF_CPU=$(F_CPU)UL
-CDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CDEFS += -DF_USB=$(F_USB)UL
 CDEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 CDEFS += $(LUFA_OPTS)
 
 
 # Place -D or -U options here for ASM sources
 ADEFS  = -DF_CPU=$(F_CPU)
-ADEFS += -DF_CLOCK=$(F_CLOCK)UL
+ADEFS += -DF_USB=$(F_USB)UL
 ADEFS += -DBOARD=BOARD_$(BOARD)
 ADEFS += $(LUFA_OPTS)
 
 # Place -D or -U options here for C++ sources
 CPPDEFS  = -DF_CPU=$(F_CPU)UL
-CPPDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CPPDEFS += -DF_USB=$(F_USB)UL
 CPPDEFS += -DBOARD=BOARD_$(BOARD)
 CPPDEFS += $(LUFA_OPTS)
 #CPPDEFS += -D__STDC_LIMIT_MACROS
diff --git a/Demos/Device/LowLevel/AudioInput/makefile b/Demos/Device/LowLevel/AudioInput/makefile
index 40746f8f93790c0310e0780d13114d22882d85da..520abbebdd04ddcc66230eb0aa55efd3f622c63d 100644
--- a/Demos/Device/LowLevel/AudioInput/makefile
+++ b/Demos/Device/LowLevel/AudioInput/makefile
@@ -79,8 +79,8 @@ BOARD = USBKEY
 #     calculate timings. Do NOT tack on a 'UL' at the end, this will be done
 #     automatically to create a 32-bit value in your source code.
 #
-#     This will be an integer division of F_CLOCK below, as it is sourced by
-#     F_CLOCK after it has run through any CPU prescalers. Note that this value
+#     This will be an integer division of F_USB below, as it is sourced by
+#     F_USB after it has run through any CPU prescalers. Note that this value
 #     does not *change* the processor frequency - it should merely be updated to
 #     reflect the processor speed set externally so that the code can use accurate
 #     software delays.
@@ -88,7 +88,7 @@ F_CPU = 8000000
 
 
 # Input clock frequency.
-#     This will define a symbol, F_CLOCK, in all source code files equal to the
+#     This will define a symbol, F_USB, in all source code files equal to the
 #     input clock frequency (before any prescaling is performed) in Hz. This value may
 #     differ from F_CPU if prescaling is used on the latter, and is required as the
 #     raw input clock is fed directly to the PLL sections of the AVR for high speed
@@ -98,7 +98,7 @@ F_CPU = 8000000
 #
 #     If no clock division is performed on the input clock inside the AVR (via the
 #     CPU clock adjust registers or the clock division fuses), this will be equal to F_CPU.
-F_CLOCK = $(F_CPU)
+F_USB = $(F_CPU)
 
 
 # Output format. (can be srec, ihex, binary)
@@ -184,20 +184,20 @@ CSTANDARD = -std=c99
 
 # Place -D or -U options here for C sources
 CDEFS  = -DF_CPU=$(F_CPU)UL
-CDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CDEFS += -DF_USB=$(F_USB)UL
 CDEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 CDEFS += $(LUFA_OPTS)
 
 
 # Place -D or -U options here for ASM sources
 ADEFS  = -DF_CPU=$(F_CPU)
-ADEFS += -DF_CLOCK=$(F_CLOCK)UL
+ADEFS += -DF_USB=$(F_USB)UL
 ADEFS += -DBOARD=BOARD_$(BOARD)
 ADEFS += $(LUFA_OPTS)
 
 # Place -D or -U options here for C++ sources
 CPPDEFS  = -DF_CPU=$(F_CPU)UL
-CPPDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CPPDEFS += -DF_USB=$(F_USB)UL
 CPPDEFS += -DBOARD=BOARD_$(BOARD)
 CPPDEFS += $(LUFA_OPTS)
 #CPPDEFS += -D__STDC_LIMIT_MACROS
diff --git a/Demos/Device/LowLevel/AudioOutput/makefile b/Demos/Device/LowLevel/AudioOutput/makefile
index 28bc1c286a83cb603e2898d45fee2f98c8160142..1623cf1557df481a2e875081d358745479bb6e6e 100644
--- a/Demos/Device/LowLevel/AudioOutput/makefile
+++ b/Demos/Device/LowLevel/AudioOutput/makefile
@@ -79,8 +79,8 @@ BOARD = USBKEY
 #     calculate timings. Do NOT tack on a 'UL' at the end, this will be done
 #     automatically to create a 32-bit value in your source code.
 #
-#     This will be an integer division of F_CLOCK below, as it is sourced by
-#     F_CLOCK after it has run through any CPU prescalers. Note that this value
+#     This will be an integer division of F_USB below, as it is sourced by
+#     F_USB after it has run through any CPU prescalers. Note that this value
 #     does not *change* the processor frequency - it should merely be updated to
 #     reflect the processor speed set externally so that the code can use accurate
 #     software delays.
@@ -88,7 +88,7 @@ F_CPU = 8000000
 
 
 # Input clock frequency.
-#     This will define a symbol, F_CLOCK, in all source code files equal to the
+#     This will define a symbol, F_USB, in all source code files equal to the
 #     input clock frequency (before any prescaling is performed) in Hz. This value may
 #     differ from F_CPU if prescaling is used on the latter, and is required as the
 #     raw input clock is fed directly to the PLL sections of the AVR for high speed
@@ -98,7 +98,7 @@ F_CPU = 8000000
 #
 #     If no clock division is performed on the input clock inside the AVR (via the
 #     CPU clock adjust registers or the clock division fuses), this will be equal to F_CPU.
-F_CLOCK = $(F_CPU)
+F_USB = $(F_CPU)
 
 
 # Output format. (can be srec, ihex, binary)
@@ -185,20 +185,20 @@ CSTANDARD = -std=c99
 
 # Place -D or -U options here for C sources
 CDEFS  = -DF_CPU=$(F_CPU)UL
-CDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CDEFS += -DF_USB=$(F_USB)UL
 CDEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 CDEFS += $(LUFA_OPTS)
 
 
 # Place -D or -U options here for ASM sources
 ADEFS  = -DF_CPU=$(F_CPU)
-ADEFS += -DF_CLOCK=$(F_CLOCK)UL
+ADEFS += -DF_USB=$(F_USB)UL
 ADEFS += -DBOARD=BOARD_$(BOARD)
 ADEFS += $(LUFA_OPTS)
 
 # Place -D or -U options here for C++ sources
 CPPDEFS  = -DF_CPU=$(F_CPU)UL
-CPPDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CPPDEFS += -DF_USB=$(F_USB)UL
 CPPDEFS += -DBOARD=BOARD_$(BOARD)
 CPPDEFS += $(LUFA_OPTS)
 #CPPDEFS += -D__STDC_LIMIT_MACROS
diff --git a/Demos/Device/LowLevel/DualVirtualSerial/makefile b/Demos/Device/LowLevel/DualVirtualSerial/makefile
index 6808429211c1c85a0ffe99658240030a7c1a14c3..f245a58dc097de0f0bbf002e0ae3eadfb1c75eb4 100644
--- a/Demos/Device/LowLevel/DualVirtualSerial/makefile
+++ b/Demos/Device/LowLevel/DualVirtualSerial/makefile
@@ -79,8 +79,8 @@ BOARD = USBKEY
 #     calculate timings. Do NOT tack on a 'UL' at the end, this will be done
 #     automatically to create a 32-bit value in your source code.
 #
-#     This will be an integer division of F_CLOCK below, as it is sourced by
-#     F_CLOCK after it has run through any CPU prescalers. Note that this value
+#     This will be an integer division of F_USB below, as it is sourced by
+#     F_USB after it has run through any CPU prescalers. Note that this value
 #     does not *change* the processor frequency - it should merely be updated to
 #     reflect the processor speed set externally so that the code can use accurate
 #     software delays.
@@ -88,7 +88,7 @@ F_CPU = 8000000
 
 
 # Input clock frequency.
-#     This will define a symbol, F_CLOCK, in all source code files equal to the
+#     This will define a symbol, F_USB, in all source code files equal to the
 #     input clock frequency (before any prescaling is performed) in Hz. This value may
 #     differ from F_CPU if prescaling is used on the latter, and is required as the
 #     raw input clock is fed directly to the PLL sections of the AVR for high speed
@@ -98,7 +98,7 @@ F_CPU = 8000000
 #
 #     If no clock division is performed on the input clock inside the AVR (via the
 #     CPU clock adjust registers or the clock division fuses), this will be equal to F_CPU.
-F_CLOCK = $(F_CPU)
+F_USB = $(F_CPU)
 
 
 # Output format. (can be srec, ihex, binary)
@@ -181,20 +181,20 @@ CSTANDARD = -std=c99
 
 # Place -D or -U options here for C sources
 CDEFS  = -DF_CPU=$(F_CPU)UL
-CDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CDEFS += -DF_USB=$(F_USB)UL
 CDEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 CDEFS += $(LUFA_OPTS)
 
 
 # Place -D or -U options here for ASM sources
 ADEFS  = -DF_CPU=$(F_CPU)
-ADEFS += -DF_CLOCK=$(F_CLOCK)UL
+ADEFS += -DF_USB=$(F_USB)UL
 ADEFS += -DBOARD=BOARD_$(BOARD)
 ADEFS += $(LUFA_OPTS)
 
 # Place -D or -U options here for C++ sources
 CPPDEFS  = -DF_CPU=$(F_CPU)UL
-CPPDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CPPDEFS += -DF_USB=$(F_USB)UL
 CPPDEFS += -DBOARD=BOARD_$(BOARD)
 CPPDEFS += $(LUFA_OPTS)
 #CPPDEFS += -D__STDC_LIMIT_MACROS
diff --git a/Demos/Device/LowLevel/GenericHID/makefile b/Demos/Device/LowLevel/GenericHID/makefile
index d87f6dc69e6b587c89b9ec83a38ffad35dfbd87a..3c707fcc8165cb76438479a5f32a8abb499a3f07 100644
--- a/Demos/Device/LowLevel/GenericHID/makefile
+++ b/Demos/Device/LowLevel/GenericHID/makefile
@@ -79,8 +79,8 @@ BOARD = USBKEY
 #     calculate timings. Do NOT tack on a 'UL' at the end, this will be done
 #     automatically to create a 32-bit value in your source code.
 #
-#     This will be an integer division of F_CLOCK below, as it is sourced by
-#     F_CLOCK after it has run through any CPU prescalers. Note that this value
+#     This will be an integer division of F_USB below, as it is sourced by
+#     F_USB after it has run through any CPU prescalers. Note that this value
 #     does not *change* the processor frequency - it should merely be updated to
 #     reflect the processor speed set externally so that the code can use accurate
 #     software delays.
@@ -88,7 +88,7 @@ F_CPU = 8000000
 
 
 # Input clock frequency.
-#     This will define a symbol, F_CLOCK, in all source code files equal to the
+#     This will define a symbol, F_USB, in all source code files equal to the
 #     input clock frequency (before any prescaling is performed) in Hz. This value may
 #     differ from F_CPU if prescaling is used on the latter, and is required as the
 #     raw input clock is fed directly to the PLL sections of the AVR for high speed
@@ -98,7 +98,7 @@ F_CPU = 8000000
 #
 #     If no clock division is performed on the input clock inside the AVR (via the
 #     CPU clock adjust registers or the clock division fuses), this will be equal to F_CPU.
-F_CLOCK = $(F_CPU)
+F_USB = $(F_CPU)
 
 
 # Output format. (can be srec, ihex, binary)
@@ -181,20 +181,20 @@ CSTANDARD = -std=c99
 
 # Place -D or -U options here for C sources
 CDEFS  = -DF_CPU=$(F_CPU)UL
-CDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CDEFS += -DF_USB=$(F_USB)UL
 CDEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 CDEFS += $(LUFA_OPTS)
 
 
 # Place -D or -U options here for ASM sources
 ADEFS  = -DF_CPU=$(F_CPU)
-ADEFS += -DF_CLOCK=$(F_CLOCK)UL
+ADEFS += -DF_USB=$(F_USB)UL
 ADEFS += -DBOARD=BOARD_$(BOARD)
 ADEFS += $(LUFA_OPTS)
 
 # Place -D or -U options here for C++ sources
 CPPDEFS  = -DF_CPU=$(F_CPU)UL
-CPPDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CPPDEFS += -DF_USB=$(F_USB)UL
 CPPDEFS += -DBOARD=BOARD_$(BOARD)
 CPPDEFS += $(LUFA_OPTS)
 #CPPDEFS += -D__STDC_LIMIT_MACROS
diff --git a/Demos/Device/LowLevel/Joystick/makefile b/Demos/Device/LowLevel/Joystick/makefile
index ba9c1589909d8db4e86f64838622a18e44d28aa5..ff10a659a45a7c4b2edc55bbf405eeeb55573409 100644
--- a/Demos/Device/LowLevel/Joystick/makefile
+++ b/Demos/Device/LowLevel/Joystick/makefile
@@ -79,8 +79,8 @@ BOARD = USBKEY
 #     calculate timings. Do NOT tack on a 'UL' at the end, this will be done
 #     automatically to create a 32-bit value in your source code.
 #
-#     This will be an integer division of F_CLOCK below, as it is sourced by
-#     F_CLOCK after it has run through any CPU prescalers. Note that this value
+#     This will be an integer division of F_USB below, as it is sourced by
+#     F_USB after it has run through any CPU prescalers. Note that this value
 #     does not *change* the processor frequency - it should merely be updated to
 #     reflect the processor speed set externally so that the code can use accurate
 #     software delays.
@@ -88,7 +88,7 @@ F_CPU = 8000000
 
 
 # Input clock frequency.
-#     This will define a symbol, F_CLOCK, in all source code files equal to the
+#     This will define a symbol, F_USB, in all source code files equal to the
 #     input clock frequency (before any prescaling is performed) in Hz. This value may
 #     differ from F_CPU if prescaling is used on the latter, and is required as the
 #     raw input clock is fed directly to the PLL sections of the AVR for high speed
@@ -98,7 +98,7 @@ F_CPU = 8000000
 #
 #     If no clock division is performed on the input clock inside the AVR (via the
 #     CPU clock adjust registers or the clock division fuses), this will be equal to F_CPU.
-F_CLOCK = $(F_CPU)
+F_USB = $(F_CPU)
 
 
 # Output format. (can be srec, ihex, binary)
@@ -181,20 +181,20 @@ CSTANDARD = -std=c99
 
 # Place -D or -U options here for C sources
 CDEFS  = -DF_CPU=$(F_CPU)UL
-CDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CDEFS += -DF_USB=$(F_USB)UL
 CDEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 CDEFS += $(LUFA_OPTS)
 
 
 # Place -D or -U options here for ASM sources
 ADEFS  = -DF_CPU=$(F_CPU)
-ADEFS += -DF_CLOCK=$(F_CLOCK)UL
+ADEFS += -DF_USB=$(F_USB)UL
 ADEFS += -DBOARD=BOARD_$(BOARD)
 ADEFS += $(LUFA_OPTS)
 
 # Place -D or -U options here for C++ sources
 CPPDEFS  = -DF_CPU=$(F_CPU)UL
-CPPDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CPPDEFS += -DF_USB=$(F_USB)UL
 CPPDEFS += -DBOARD=BOARD_$(BOARD)
 CPPDEFS += $(LUFA_OPTS)
 #CPPDEFS += -D__STDC_LIMIT_MACROS
diff --git a/Demos/Device/LowLevel/Keyboard/makefile b/Demos/Device/LowLevel/Keyboard/makefile
index 3e764d9d72c3e41d9bee26dd2fd772662f784255..7f29e0631bf663759ef21c53fc68c07a23a180ee 100644
--- a/Demos/Device/LowLevel/Keyboard/makefile
+++ b/Demos/Device/LowLevel/Keyboard/makefile
@@ -79,8 +79,8 @@ BOARD = USBKEY
 #     calculate timings. Do NOT tack on a 'UL' at the end, this will be done
 #     automatically to create a 32-bit value in your source code.
 #
-#     This will be an integer division of F_CLOCK below, as it is sourced by
-#     F_CLOCK after it has run through any CPU prescalers. Note that this value
+#     This will be an integer division of F_USB below, as it is sourced by
+#     F_USB after it has run through any CPU prescalers. Note that this value
 #     does not *change* the processor frequency - it should merely be updated to
 #     reflect the processor speed set externally so that the code can use accurate
 #     software delays.
@@ -88,7 +88,7 @@ F_CPU = 8000000
 
 
 # Input clock frequency.
-#     This will define a symbol, F_CLOCK, in all source code files equal to the
+#     This will define a symbol, F_USB, in all source code files equal to the
 #     input clock frequency (before any prescaling is performed) in Hz. This value may
 #     differ from F_CPU if prescaling is used on the latter, and is required as the
 #     raw input clock is fed directly to the PLL sections of the AVR for high speed
@@ -98,7 +98,7 @@ F_CPU = 8000000
 #
 #     If no clock division is performed on the input clock inside the AVR (via the
 #     CPU clock adjust registers or the clock division fuses), this will be equal to F_CPU.
-F_CLOCK = $(F_CPU)
+F_USB = $(F_CPU)
 
 
 # Output format. (can be srec, ihex, binary)
@@ -181,20 +181,20 @@ CSTANDARD = -std=c99
 
 # Place -D or -U options here for C sources
 CDEFS  = -DF_CPU=$(F_CPU)UL
-CDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CDEFS += -DF_USB=$(F_USB)UL
 CDEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 CDEFS += $(LUFA_OPTS)
 
 
 # Place -D or -U options here for ASM sources
 ADEFS  = -DF_CPU=$(F_CPU)
-ADEFS += -DF_CLOCK=$(F_CLOCK)UL
+ADEFS += -DF_USB=$(F_USB)UL
 ADEFS += -DBOARD=BOARD_$(BOARD)
 ADEFS += $(LUFA_OPTS)
 
 # Place -D or -U options here for C++ sources
 CPPDEFS  = -DF_CPU=$(F_CPU)UL
-CPPDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CPPDEFS += -DF_USB=$(F_USB)UL
 CPPDEFS += -DBOARD=BOARD_$(BOARD)
 CPPDEFS += $(LUFA_OPTS)
 #CPPDEFS += -D__STDC_LIMIT_MACROS
diff --git a/Demos/Device/LowLevel/KeyboardMouse/makefile b/Demos/Device/LowLevel/KeyboardMouse/makefile
index 12490fc614bd311a79d4f22b9caf528f5d3b573b..98f9e128544e45b3b5b37899d62e35fcf338ace3 100644
--- a/Demos/Device/LowLevel/KeyboardMouse/makefile
+++ b/Demos/Device/LowLevel/KeyboardMouse/makefile
@@ -79,8 +79,8 @@ BOARD = USBKEY
 #     calculate timings. Do NOT tack on a 'UL' at the end, this will be done
 #     automatically to create a 32-bit value in your source code.
 #
-#     This will be an integer division of F_CLOCK below, as it is sourced by
-#     F_CLOCK after it has run through any CPU prescalers. Note that this value
+#     This will be an integer division of F_USB below, as it is sourced by
+#     F_USB after it has run through any CPU prescalers. Note that this value
 #     does not *change* the processor frequency - it should merely be updated to
 #     reflect the processor speed set externally so that the code can use accurate
 #     software delays.
@@ -88,7 +88,7 @@ F_CPU = 8000000
 
 
 # Input clock frequency.
-#     This will define a symbol, F_CLOCK, in all source code files equal to the
+#     This will define a symbol, F_USB, in all source code files equal to the
 #     input clock frequency (before any prescaling is performed) in Hz. This value may
 #     differ from F_CPU if prescaling is used on the latter, and is required as the
 #     raw input clock is fed directly to the PLL sections of the AVR for high speed
@@ -98,7 +98,7 @@ F_CPU = 8000000
 #
 #     If no clock division is performed on the input clock inside the AVR (via the
 #     CPU clock adjust registers or the clock division fuses), this will be equal to F_CPU.
-F_CLOCK = $(F_CPU)
+F_USB = $(F_CPU)
 
 
 # Output format. (can be srec, ihex, binary)
@@ -181,20 +181,20 @@ CSTANDARD = -std=c99
 
 # Place -D or -U options here for C sources
 CDEFS  = -DF_CPU=$(F_CPU)UL
-CDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CDEFS += -DF_USB=$(F_USB)UL
 CDEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 CDEFS += $(LUFA_OPTS)
 
 
 # Place -D or -U options here for ASM sources
 ADEFS  = -DF_CPU=$(F_CPU)
-ADEFS += -DF_CLOCK=$(F_CLOCK)UL
+ADEFS += -DF_USB=$(F_USB)UL
 ADEFS += -DBOARD=BOARD_$(BOARD)
 ADEFS += $(LUFA_OPTS)
 
 # Place -D or -U options here for C++ sources
 CPPDEFS  = -DF_CPU=$(F_CPU)UL
-CPPDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CPPDEFS += -DF_USB=$(F_USB)UL
 CPPDEFS += -DBOARD=BOARD_$(BOARD)
 CPPDEFS += $(LUFA_OPTS)
 #CPPDEFS += -D__STDC_LIMIT_MACROS
diff --git a/Demos/Device/LowLevel/MIDI/makefile b/Demos/Device/LowLevel/MIDI/makefile
index 7b8a242c49339708ff593dd2bf3b12d033086616..079fae94b93c326d1188a2e436876475ef0c6b98 100644
--- a/Demos/Device/LowLevel/MIDI/makefile
+++ b/Demos/Device/LowLevel/MIDI/makefile
@@ -79,8 +79,8 @@ BOARD = USBKEY
 #     calculate timings. Do NOT tack on a 'UL' at the end, this will be done
 #     automatically to create a 32-bit value in your source code.
 #
-#     This will be an integer division of F_CLOCK below, as it is sourced by
-#     F_CLOCK after it has run through any CPU prescalers. Note that this value
+#     This will be an integer division of F_USB below, as it is sourced by
+#     F_USB after it has run through any CPU prescalers. Note that this value
 #     does not *change* the processor frequency - it should merely be updated to
 #     reflect the processor speed set externally so that the code can use accurate
 #     software delays.
@@ -88,7 +88,7 @@ F_CPU = 8000000
 
 
 # Input clock frequency.
-#     This will define a symbol, F_CLOCK, in all source code files equal to the
+#     This will define a symbol, F_USB, in all source code files equal to the
 #     input clock frequency (before any prescaling is performed) in Hz. This value may
 #     differ from F_CPU if prescaling is used on the latter, and is required as the
 #     raw input clock is fed directly to the PLL sections of the AVR for high speed
@@ -98,7 +98,7 @@ F_CPU = 8000000
 #
 #     If no clock division is performed on the input clock inside the AVR (via the
 #     CPU clock adjust registers or the clock division fuses), this will be equal to F_CPU.
-F_CLOCK = $(F_CPU)
+F_USB = $(F_CPU)
 
 
 # Output format. (can be srec, ihex, binary)
@@ -181,20 +181,20 @@ CSTANDARD = -std=c99
 
 # Place -D or -U options here for C sources
 CDEFS  = -DF_CPU=$(F_CPU)UL
-CDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CDEFS += -DF_USB=$(F_USB)UL
 CDEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 CDEFS += $(LUFA_OPTS)
 
 
 # Place -D or -U options here for ASM sources
 ADEFS  = -DF_CPU=$(F_CPU)
-ADEFS += -DF_CLOCK=$(F_CLOCK)UL
+ADEFS += -DF_USB=$(F_USB)UL
 ADEFS += -DBOARD=BOARD_$(BOARD)
 ADEFS += $(LUFA_OPTS)
 
 # Place -D or -U options here for C++ sources
 CPPDEFS  = -DF_CPU=$(F_CPU)UL
-CPPDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CPPDEFS += -DF_USB=$(F_USB)UL
 CPPDEFS += -DBOARD=BOARD_$(BOARD)
 CPPDEFS += $(LUFA_OPTS)
 #CPPDEFS += -D__STDC_LIMIT_MACROS
diff --git a/Demos/Device/LowLevel/MassStorage/makefile b/Demos/Device/LowLevel/MassStorage/makefile
index becdfab0f51ea578b633ac947784b55ed3c5a99e..7e72a987a2a68569a2a8983c53c45a3ae833293b 100644
--- a/Demos/Device/LowLevel/MassStorage/makefile
+++ b/Demos/Device/LowLevel/MassStorage/makefile
@@ -79,8 +79,8 @@ BOARD = USBKEY
 #     calculate timings. Do NOT tack on a 'UL' at the end, this will be done
 #     automatically to create a 32-bit value in your source code.
 #
-#     This will be an integer division of F_CLOCK below, as it is sourced by
-#     F_CLOCK after it has run through any CPU prescalers. Note that this value
+#     This will be an integer division of F_USB below, as it is sourced by
+#     F_USB after it has run through any CPU prescalers. Note that this value
 #     does not *change* the processor frequency - it should merely be updated to
 #     reflect the processor speed set externally so that the code can use accurate
 #     software delays.
@@ -88,7 +88,7 @@ F_CPU = 8000000
 
 
 # Input clock frequency.
-#     This will define a symbol, F_CLOCK, in all source code files equal to the
+#     This will define a symbol, F_USB, in all source code files equal to the
 #     input clock frequency (before any prescaling is performed) in Hz. This value may
 #     differ from F_CPU if prescaling is used on the latter, and is required as the
 #     raw input clock is fed directly to the PLL sections of the AVR for high speed
@@ -98,7 +98,7 @@ F_CPU = 8000000
 #
 #     If no clock division is performed on the input clock inside the AVR (via the
 #     CPU clock adjust registers or the clock division fuses), this will be equal to F_CPU.
-F_CLOCK = $(F_CPU)
+F_USB = $(F_CPU)
 
 
 # Output format. (can be srec, ihex, binary)
@@ -184,20 +184,20 @@ CSTANDARD = -std=c99
 
 # Place -D or -U options here for C sources
 CDEFS  = -DF_CPU=$(F_CPU)UL
-CDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CDEFS += -DF_USB=$(F_USB)UL
 CDEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 CDEFS += $(LUFA_OPTS)
 
 
 # Place -D or -U options here for ASM sources
 ADEFS  = -DF_CPU=$(F_CPU)
-ADEFS += -DF_CLOCK=$(F_CLOCK)UL
+ADEFS += -DF_USB=$(F_USB)UL
 ADEFS += -DBOARD=BOARD_$(BOARD)
 ADEFS += $(LUFA_OPTS)
 
 # Place -D or -U options here for C++ sources
 CPPDEFS  = -DF_CPU=$(F_CPU)UL
-CPPDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CPPDEFS += -DF_USB=$(F_USB)UL
 CPPDEFS += -DBOARD=BOARD_$(BOARD)
 CPPDEFS += $(LUFA_OPTS)
 #CPPDEFS += -D__STDC_LIMIT_MACROS
diff --git a/Demos/Device/LowLevel/Mouse/makefile b/Demos/Device/LowLevel/Mouse/makefile
index 7b8d8eea215ddc12b512fdb31e8a802063b6422c..a962a80d298578e593bf9328f8e562809139f984 100644
--- a/Demos/Device/LowLevel/Mouse/makefile
+++ b/Demos/Device/LowLevel/Mouse/makefile
@@ -79,8 +79,8 @@ BOARD = USBKEY
 #     calculate timings. Do NOT tack on a 'UL' at the end, this will be done
 #     automatically to create a 32-bit value in your source code.
 #
-#     This will be an integer division of F_CLOCK below, as it is sourced by
-#     F_CLOCK after it has run through any CPU prescalers. Note that this value
+#     This will be an integer division of F_USB below, as it is sourced by
+#     F_USB after it has run through any CPU prescalers. Note that this value
 #     does not *change* the processor frequency - it should merely be updated to
 #     reflect the processor speed set externally so that the code can use accurate
 #     software delays.
@@ -88,7 +88,7 @@ F_CPU = 8000000
 
 
 # Input clock frequency.
-#     This will define a symbol, F_CLOCK, in all source code files equal to the
+#     This will define a symbol, F_USB, in all source code files equal to the
 #     input clock frequency (before any prescaling is performed) in Hz. This value may
 #     differ from F_CPU if prescaling is used on the latter, and is required as the
 #     raw input clock is fed directly to the PLL sections of the AVR for high speed
@@ -98,7 +98,7 @@ F_CPU = 8000000
 #
 #     If no clock division is performed on the input clock inside the AVR (via the
 #     CPU clock adjust registers or the clock division fuses), this will be equal to F_CPU.
-F_CLOCK = $(F_CPU)
+F_USB = $(F_CPU)
 
 
 # Output format. (can be srec, ihex, binary)
@@ -181,20 +181,20 @@ CSTANDARD = -std=c99
 
 # Place -D or -U options here for C sources
 CDEFS  = -DF_CPU=$(F_CPU)UL
-CDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CDEFS += -DF_USB=$(F_USB)UL
 CDEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 CDEFS += $(LUFA_OPTS)
 
 
 # Place -D or -U options here for ASM sources
 ADEFS  = -DF_CPU=$(F_CPU)
-ADEFS += -DF_CLOCK=$(F_CLOCK)UL
+ADEFS += -DF_USB=$(F_USB)UL
 ADEFS += -DBOARD=BOARD_$(BOARD)
 ADEFS += $(LUFA_OPTS)
 
 # Place -D or -U options here for C++ sources
 CPPDEFS  = -DF_CPU=$(F_CPU)UL
-CPPDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CPPDEFS += -DF_USB=$(F_USB)UL
 CPPDEFS += -DBOARD=BOARD_$(BOARD)
 CPPDEFS += $(LUFA_OPTS)
 #CPPDEFS += -D__STDC_LIMIT_MACROS
diff --git a/Demos/Device/LowLevel/RNDISEthernet/makefile b/Demos/Device/LowLevel/RNDISEthernet/makefile
index 66528646dd7d3d46acd61131ebec6558ab57ad59..37d90f9bcacd0533669f079e45e9c23e277b24c6 100644
--- a/Demos/Device/LowLevel/RNDISEthernet/makefile
+++ b/Demos/Device/LowLevel/RNDISEthernet/makefile
@@ -79,8 +79,8 @@ BOARD = USBKEY
 #     calculate timings. Do NOT tack on a 'UL' at the end, this will be done
 #     automatically to create a 32-bit value in your source code.
 #
-#     This will be an integer division of F_CLOCK below, as it is sourced by
-#     F_CLOCK after it has run through any CPU prescalers. Note that this value
+#     This will be an integer division of F_USB below, as it is sourced by
+#     F_USB after it has run through any CPU prescalers. Note that this value
 #     does not *change* the processor frequency - it should merely be updated to
 #     reflect the processor speed set externally so that the code can use accurate
 #     software delays.
@@ -88,7 +88,7 @@ F_CPU = 8000000
 
 
 # Input clock frequency.
-#     This will define a symbol, F_CLOCK, in all source code files equal to the
+#     This will define a symbol, F_USB, in all source code files equal to the
 #     input clock frequency (before any prescaling is performed) in Hz. This value may
 #     differ from F_CPU if prescaling is used on the latter, and is required as the
 #     raw input clock is fed directly to the PLL sections of the AVR for high speed
@@ -98,7 +98,7 @@ F_CPU = 8000000
 #
 #     If no clock division is performed on the input clock inside the AVR (via the
 #     CPU clock adjust registers or the clock division fuses), this will be equal to F_CPU.
-F_CLOCK = $(F_CPU)
+F_USB = $(F_CPU)
 
 
 # Output format. (can be srec, ihex, binary)
@@ -200,20 +200,20 @@ CSTANDARD = -std=c99
 
 # Place -D or -U options here for C sources
 CDEFS  = -DF_CPU=$(F_CPU)UL
-CDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CDEFS += -DF_USB=$(F_USB)UL
 CDEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 CDEFS += $(LUFA_OPTS)
 
 
 # Place -D or -U options here for ASM sources
 ADEFS  = -DF_CPU=$(F_CPU)
-ADEFS += -DF_CLOCK=$(F_CLOCK)UL
+ADEFS += -DF_USB=$(F_USB)UL
 ADEFS += -DBOARD=BOARD_$(BOARD)
 ADEFS += $(LUFA_OPTS)
 
 # Place -D or -U options here for C++ sources
 CPPDEFS  = -DF_CPU=$(F_CPU)UL
-CPPDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CPPDEFS += -DF_USB=$(F_USB)UL
 CPPDEFS += -DBOARD=BOARD_$(BOARD)
 CPPDEFS += $(LUFA_OPTS)
 #CPPDEFS += -D__STDC_LIMIT_MACROS
diff --git a/Demos/Device/LowLevel/VirtualSerial/makefile b/Demos/Device/LowLevel/VirtualSerial/makefile
index fd13fc64e61a88b2af7173587f9ac77ff52302b5..ba8911850eed8f10acd7a51bcabd39fd2e1cf923 100644
--- a/Demos/Device/LowLevel/VirtualSerial/makefile
+++ b/Demos/Device/LowLevel/VirtualSerial/makefile
@@ -79,8 +79,8 @@ BOARD = USBKEY
 #     calculate timings. Do NOT tack on a 'UL' at the end, this will be done
 #     automatically to create a 32-bit value in your source code.
 #
-#     This will be an integer division of F_CLOCK below, as it is sourced by
-#     F_CLOCK after it has run through any CPU prescalers. Note that this value
+#     This will be an integer division of F_USB below, as it is sourced by
+#     F_USB after it has run through any CPU prescalers. Note that this value
 #     does not *change* the processor frequency - it should merely be updated to
 #     reflect the processor speed set externally so that the code can use accurate
 #     software delays.
@@ -88,7 +88,7 @@ F_CPU = 8000000
 
 
 # Input clock frequency.
-#     This will define a symbol, F_CLOCK, in all source code files equal to the
+#     This will define a symbol, F_USB, in all source code files equal to the
 #     input clock frequency (before any prescaling is performed) in Hz. This value may
 #     differ from F_CPU if prescaling is used on the latter, and is required as the
 #     raw input clock is fed directly to the PLL sections of the AVR for high speed
@@ -98,7 +98,7 @@ F_CPU = 8000000
 #
 #     If no clock division is performed on the input clock inside the AVR (via the
 #     CPU clock adjust registers or the clock division fuses), this will be equal to F_CPU.
-F_CLOCK = $(F_CPU)
+F_USB = $(F_CPU)
 
 
 # Output format. (can be srec, ihex, binary)
@@ -181,20 +181,20 @@ CSTANDARD = -std=c99
 
 # Place -D or -U options here for C sources
 CDEFS  = -DF_CPU=$(F_CPU)UL
-CDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CDEFS += -DF_USB=$(F_USB)UL
 CDEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 CDEFS += $(LUFA_OPTS)
 
 
 # Place -D or -U options here for ASM sources
 ADEFS  = -DF_CPU=$(F_CPU)
-ADEFS += -DF_CLOCK=$(F_CLOCK)UL
+ADEFS += -DF_USB=$(F_USB)UL
 ADEFS += -DBOARD=BOARD_$(BOARD)
 ADEFS += $(LUFA_OPTS)
 
 # Place -D or -U options here for C++ sources
 CPPDEFS  = -DF_CPU=$(F_CPU)UL
-CPPDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CPPDEFS += -DF_USB=$(F_USB)UL
 CPPDEFS += -DBOARD=BOARD_$(BOARD)
 CPPDEFS += $(LUFA_OPTS)
 #CPPDEFS += -D__STDC_LIMIT_MACROS
diff --git a/Demos/DualRole/ClassDriver/MouseHostDevice/makefile b/Demos/DualRole/ClassDriver/MouseHostDevice/makefile
index c9b74eb2bfa0dede005229bac38982fdd34da052..db646f3524f59cfc1c2aee81c1223ceeccfa5193 100644
--- a/Demos/DualRole/ClassDriver/MouseHostDevice/makefile
+++ b/Demos/DualRole/ClassDriver/MouseHostDevice/makefile
@@ -79,8 +79,8 @@ BOARD = USBKEY
 #     calculate timings. Do NOT tack on a 'UL' at the end, this will be done
 #     automatically to create a 32-bit value in your source code.
 #
-#     This will be an integer division of F_CLOCK below, as it is sourced by
-#     F_CLOCK after it has run through any CPU prescalers. Note that this value
+#     This will be an integer division of F_USB below, as it is sourced by
+#     F_USB after it has run through any CPU prescalers. Note that this value
 #     does not *change* the processor frequency - it should merely be updated to
 #     reflect the processor speed set externally so that the code can use accurate
 #     software delays.
@@ -88,7 +88,7 @@ F_CPU = 8000000
 
 
 # Input clock frequency.
-#     This will define a symbol, F_CLOCK, in all source code files equal to the
+#     This will define a symbol, F_USB, in all source code files equal to the
 #     input clock frequency (before any prescaling is performed) in Hz. This value may
 #     differ from F_CPU if prescaling is used on the latter, and is required as the
 #     raw input clock is fed directly to the PLL sections of the AVR for high speed
@@ -98,7 +98,7 @@ F_CPU = 8000000
 #
 #     If no clock division is performed on the input clock inside the AVR (via the
 #     CPU clock adjust registers or the clock division fuses), this will be equal to F_CPU.
-F_CLOCK = $(F_CPU)
+F_USB = $(F_CPU)
 
 
 # Output format. (can be srec, ihex, binary)
@@ -184,20 +184,20 @@ CSTANDARD = -std=c99
 
 # Place -D or -U options here for C sources
 CDEFS  = -DF_CPU=$(F_CPU)UL
-CDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CDEFS += -DF_USB=$(F_USB)UL
 CDEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 CDEFS += $(LUFA_OPTS)
 
 
 # Place -D or -U options here for ASM sources
 ADEFS  = -DF_CPU=$(F_CPU)
-ADEFS += -DF_CLOCK=$(F_CLOCK)UL
+ADEFS += -DF_USB=$(F_USB)UL
 ADEFS += -DBOARD=BOARD_$(BOARD)
 ADEFS += $(LUFA_OPTS)
 
 # Place -D or -U options here for C++ sources
 CPPDEFS  = -DF_CPU=$(F_CPU)UL
-CPPDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CPPDEFS += -DF_USB=$(F_USB)UL
 CPPDEFS += -DBOARD=BOARD_$(BOARD)
 CPPDEFS += $(LUFA_OPTS)
 #CPPDEFS += -D__STDC_LIMIT_MACROS
diff --git a/Demos/Host/ClassDriver/JoystickHostWithParser/makefile b/Demos/Host/ClassDriver/JoystickHostWithParser/makefile
index f72c1e3006aa58157d44afc8c33c374d58be31c9..e5c3429a9af5b01b04a21b5174b4d416f8353318 100644
--- a/Demos/Host/ClassDriver/JoystickHostWithParser/makefile
+++ b/Demos/Host/ClassDriver/JoystickHostWithParser/makefile
@@ -79,8 +79,8 @@ BOARD = USBKEY
 #     calculate timings. Do NOT tack on a 'UL' at the end, this will be done
 #     automatically to create a 32-bit value in your source code.
 #
-#     This will be an integer division of F_CLOCK below, as it is sourced by
-#     F_CLOCK after it has run through any CPU prescalers. Note that this value
+#     This will be an integer division of F_USB below, as it is sourced by
+#     F_USB after it has run through any CPU prescalers. Note that this value
 #     does not *change* the processor frequency - it should merely be updated to
 #     reflect the processor speed set externally so that the code can use accurate
 #     software delays.
@@ -88,7 +88,7 @@ F_CPU = 8000000
 
 
 # Input clock frequency.
-#     This will define a symbol, F_CLOCK, in all source code files equal to the
+#     This will define a symbol, F_USB, in all source code files equal to the
 #     input clock frequency (before any prescaling is performed) in Hz. This value may
 #     differ from F_CPU if prescaling is used on the latter, and is required as the
 #     raw input clock is fed directly to the PLL sections of the AVR for high speed
@@ -98,7 +98,7 @@ F_CPU = 8000000
 #
 #     If no clock division is performed on the input clock inside the AVR (via the
 #     CPU clock adjust registers or the clock division fuses), this will be equal to F_CPU.
-F_CLOCK = $(F_CPU)
+F_USB = $(F_CPU)
 
 
 # Output format. (can be srec, ihex, binary)
@@ -179,20 +179,20 @@ CSTANDARD = -std=c99
 
 # Place -D or -U options here for C sources
 CDEFS  = -DF_CPU=$(F_CPU)UL
-CDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CDEFS += -DF_USB=$(F_USB)UL
 CDEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 CDEFS += $(LUFA_OPTS)
 
 
 # Place -D or -U options here for ASM sources
 ADEFS  = -DF_CPU=$(F_CPU)
-ADEFS += -DF_CLOCK=$(F_CLOCK)UL
+ADEFS += -DF_USB=$(F_USB)UL
 ADEFS += -DBOARD=BOARD_$(BOARD)
 ADEFS += $(LUFA_OPTS)
 
 # Place -D or -U options here for C++ sources
 CPPDEFS  = -DF_CPU=$(F_CPU)UL
-CPPDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CPPDEFS += -DF_USB=$(F_USB)UL
 CPPDEFS += -DBOARD=BOARD_$(BOARD)
 CPPDEFS += $(LUFA_OPTS)
 #CPPDEFS += -D__STDC_LIMIT_MACROS
diff --git a/Demos/Host/ClassDriver/KeyboardHost/makefile b/Demos/Host/ClassDriver/KeyboardHost/makefile
index ba0e92fe03e9d4ef87bf51001bd41509c5ea2303..4eb6968120fa949e9d0a14a60fbbc5bccd289429 100644
--- a/Demos/Host/ClassDriver/KeyboardHost/makefile
+++ b/Demos/Host/ClassDriver/KeyboardHost/makefile
@@ -79,8 +79,8 @@ BOARD = USBKEY
 #     calculate timings. Do NOT tack on a 'UL' at the end, this will be done
 #     automatically to create a 32-bit value in your source code.
 #
-#     This will be an integer division of F_CLOCK below, as it is sourced by
-#     F_CLOCK after it has run through any CPU prescalers. Note that this value
+#     This will be an integer division of F_USB below, as it is sourced by
+#     F_USB after it has run through any CPU prescalers. Note that this value
 #     does not *change* the processor frequency - it should merely be updated to
 #     reflect the processor speed set externally so that the code can use accurate
 #     software delays.
@@ -88,7 +88,7 @@ F_CPU = 8000000
 
 
 # Input clock frequency.
-#     This will define a symbol, F_CLOCK, in all source code files equal to the
+#     This will define a symbol, F_USB, in all source code files equal to the
 #     input clock frequency (before any prescaling is performed) in Hz. This value may
 #     differ from F_CPU if prescaling is used on the latter, and is required as the
 #     raw input clock is fed directly to the PLL sections of the AVR for high speed
@@ -98,7 +98,7 @@ F_CPU = 8000000
 #
 #     If no clock division is performed on the input clock inside the AVR (via the
 #     CPU clock adjust registers or the clock division fuses), this will be equal to F_CPU.
-F_CLOCK = $(F_CPU)
+F_USB = $(F_CPU)
 
 
 # Output format. (can be srec, ihex, binary)
@@ -179,20 +179,20 @@ CSTANDARD = -std=c99
 
 # Place -D or -U options here for C sources
 CDEFS  = -DF_CPU=$(F_CPU)UL
-CDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CDEFS += -DF_USB=$(F_USB)UL
 CDEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 CDEFS += $(LUFA_OPTS)
 
 
 # Place -D or -U options here for ASM sources
 ADEFS  = -DF_CPU=$(F_CPU)
-ADEFS += -DF_CLOCK=$(F_CLOCK)UL
+ADEFS += -DF_USB=$(F_USB)UL
 ADEFS += -DBOARD=BOARD_$(BOARD)
 ADEFS += $(LUFA_OPTS)
 
 # Place -D or -U options here for C++ sources
 CPPDEFS  = -DF_CPU=$(F_CPU)UL
-CPPDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CPPDEFS += -DF_USB=$(F_USB)UL
 CPPDEFS += -DBOARD=BOARD_$(BOARD)
 CPPDEFS += $(LUFA_OPTS)
 #CPPDEFS += -D__STDC_LIMIT_MACROS
diff --git a/Demos/Host/ClassDriver/KeyboardHostWithParser/makefile b/Demos/Host/ClassDriver/KeyboardHostWithParser/makefile
index b1070f9c822ecdaf2e52032a096abed579f28672..171d4cdd5f28015e00d79e73b5be9bffdcd68702 100644
--- a/Demos/Host/ClassDriver/KeyboardHostWithParser/makefile
+++ b/Demos/Host/ClassDriver/KeyboardHostWithParser/makefile
@@ -79,8 +79,8 @@ BOARD = USBKEY
 #     calculate timings. Do NOT tack on a 'UL' at the end, this will be done
 #     automatically to create a 32-bit value in your source code.
 #
-#     This will be an integer division of F_CLOCK below, as it is sourced by
-#     F_CLOCK after it has run through any CPU prescalers. Note that this value
+#     This will be an integer division of F_USB below, as it is sourced by
+#     F_USB after it has run through any CPU prescalers. Note that this value
 #     does not *change* the processor frequency - it should merely be updated to
 #     reflect the processor speed set externally so that the code can use accurate
 #     software delays.
@@ -88,7 +88,7 @@ F_CPU = 8000000
 
 
 # Input clock frequency.
-#     This will define a symbol, F_CLOCK, in all source code files equal to the
+#     This will define a symbol, F_USB, in all source code files equal to the
 #     input clock frequency (before any prescaling is performed) in Hz. This value may
 #     differ from F_CPU if prescaling is used on the latter, and is required as the
 #     raw input clock is fed directly to the PLL sections of the AVR for high speed
@@ -98,7 +98,7 @@ F_CPU = 8000000
 #
 #     If no clock division is performed on the input clock inside the AVR (via the
 #     CPU clock adjust registers or the clock division fuses), this will be equal to F_CPU.
-F_CLOCK = $(F_CPU)
+F_USB = $(F_CPU)
 
 
 # Output format. (can be srec, ihex, binary)
@@ -179,20 +179,20 @@ CSTANDARD = -std=c99
 
 # Place -D or -U options here for C sources
 CDEFS  = -DF_CPU=$(F_CPU)UL
-CDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CDEFS += -DF_USB=$(F_USB)UL
 CDEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 CDEFS += $(LUFA_OPTS)
 
 
 # Place -D or -U options here for ASM sources
 ADEFS  = -DF_CPU=$(F_CPU)
-ADEFS += -DF_CLOCK=$(F_CLOCK)UL
+ADEFS += -DF_USB=$(F_USB)UL
 ADEFS += -DBOARD=BOARD_$(BOARD)
 ADEFS += $(LUFA_OPTS)
 
 # Place -D or -U options here for C++ sources
 CPPDEFS  = -DF_CPU=$(F_CPU)UL
-CPPDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CPPDEFS += -DF_USB=$(F_USB)UL
 CPPDEFS += -DBOARD=BOARD_$(BOARD)
 CPPDEFS += $(LUFA_OPTS)
 #CPPDEFS += -D__STDC_LIMIT_MACROS
diff --git a/Demos/Host/ClassDriver/MIDIHost/makefile b/Demos/Host/ClassDriver/MIDIHost/makefile
index 99e529f4ddcc0e3bed21ae5d59794ab9571a0465..39fcc705afb3a0b842e17cc54b3618edb48c1e86 100644
--- a/Demos/Host/ClassDriver/MIDIHost/makefile
+++ b/Demos/Host/ClassDriver/MIDIHost/makefile
@@ -79,8 +79,8 @@ BOARD = USBKEY
 #     calculate timings. Do NOT tack on a 'UL' at the end, this will be done
 #     automatically to create a 32-bit value in your source code.
 #
-#     This will be an integer division of F_CLOCK below, as it is sourced by
-#     F_CLOCK after it has run through any CPU prescalers. Note that this value
+#     This will be an integer division of F_USB below, as it is sourced by
+#     F_USB after it has run through any CPU prescalers. Note that this value
 #     does not *change* the processor frequency - it should merely be updated to
 #     reflect the processor speed set externally so that the code can use accurate
 #     software delays.
@@ -88,7 +88,7 @@ F_CPU = 8000000
 
 
 # Input clock frequency.
-#     This will define a symbol, F_CLOCK, in all source code files equal to the
+#     This will define a symbol, F_USB, in all source code files equal to the
 #     input clock frequency (before any prescaling is performed) in Hz. This value may
 #     differ from F_CPU if prescaling is used on the latter, and is required as the
 #     raw input clock is fed directly to the PLL sections of the AVR for high speed
@@ -98,7 +98,7 @@ F_CPU = 8000000
 #
 #     If no clock division is performed on the input clock inside the AVR (via the
 #     CPU clock adjust registers or the clock division fuses), this will be equal to F_CPU.
-F_CLOCK = $(F_CPU)
+F_USB = $(F_CPU)
 
 
 # Output format. (can be srec, ihex, binary)
@@ -179,20 +179,20 @@ CSTANDARD = -std=c99
 
 # Place -D or -U options here for C sources
 CDEFS  = -DF_CPU=$(F_CPU)UL
-CDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CDEFS += -DF_USB=$(F_USB)UL
 CDEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 CDEFS += $(LUFA_OPTS)
 
 
 # Place -D or -U options here for ASM sources
 ADEFS  = -DF_CPU=$(F_CPU)
-ADEFS += -DF_CLOCK=$(F_CLOCK)UL
+ADEFS += -DF_USB=$(F_USB)UL
 ADEFS += -DBOARD=BOARD_$(BOARD)
 ADEFS += $(LUFA_OPTS)
 
 # Place -D or -U options here for C++ sources
 CPPDEFS  = -DF_CPU=$(F_CPU)UL
-CPPDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CPPDEFS += -DF_USB=$(F_USB)UL
 CPPDEFS += -DBOARD=BOARD_$(BOARD)
 CPPDEFS += $(LUFA_OPTS)
 #CPPDEFS += -D__STDC_LIMIT_MACROS
diff --git a/Demos/Host/ClassDriver/MassStorageHost/makefile b/Demos/Host/ClassDriver/MassStorageHost/makefile
index 22b9b14caf22e72494c454fad8acc45607143ebf..8cbf111e65e68d74abc3a1863714bb27d1e61295 100644
--- a/Demos/Host/ClassDriver/MassStorageHost/makefile
+++ b/Demos/Host/ClassDriver/MassStorageHost/makefile
@@ -79,8 +79,8 @@ BOARD = USBKEY
 #     calculate timings. Do NOT tack on a 'UL' at the end, this will be done
 #     automatically to create a 32-bit value in your source code.
 #
-#     This will be an integer division of F_CLOCK below, as it is sourced by
-#     F_CLOCK after it has run through any CPU prescalers. Note that this value
+#     This will be an integer division of F_USB below, as it is sourced by
+#     F_USB after it has run through any CPU prescalers. Note that this value
 #     does not *change* the processor frequency - it should merely be updated to
 #     reflect the processor speed set externally so that the code can use accurate
 #     software delays.
@@ -88,7 +88,7 @@ F_CPU = 8000000
 
 
 # Input clock frequency.
-#     This will define a symbol, F_CLOCK, in all source code files equal to the
+#     This will define a symbol, F_USB, in all source code files equal to the
 #     input clock frequency (before any prescaling is performed) in Hz. This value may
 #     differ from F_CPU if prescaling is used on the latter, and is required as the
 #     raw input clock is fed directly to the PLL sections of the AVR for high speed
@@ -98,7 +98,7 @@ F_CPU = 8000000
 #
 #     If no clock division is performed on the input clock inside the AVR (via the
 #     CPU clock adjust registers or the clock division fuses), this will be equal to F_CPU.
-F_CLOCK = $(F_CPU)
+F_USB = $(F_CPU)
 
 
 # Output format. (can be srec, ihex, binary)
@@ -180,20 +180,20 @@ CSTANDARD = -std=c99
 
 # Place -D or -U options here for C sources
 CDEFS  = -DF_CPU=$(F_CPU)UL
-CDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CDEFS += -DF_USB=$(F_USB)UL
 CDEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 CDEFS += $(LUFA_OPTS)
 
 
 # Place -D or -U options here for ASM sources
 ADEFS  = -DF_CPU=$(F_CPU)
-ADEFS += -DF_CLOCK=$(F_CLOCK)UL
+ADEFS += -DF_USB=$(F_USB)UL
 ADEFS += -DBOARD=BOARD_$(BOARD)
 ADEFS += $(LUFA_OPTS)
 
 # Place -D or -U options here for C++ sources
 CPPDEFS  = -DF_CPU=$(F_CPU)UL
-CPPDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CPPDEFS += -DF_USB=$(F_USB)UL
 CPPDEFS += -DBOARD=BOARD_$(BOARD)
 CPPDEFS += $(LUFA_OPTS)
 #CPPDEFS += -D__STDC_LIMIT_MACROS
diff --git a/Demos/Host/ClassDriver/MouseHost/makefile b/Demos/Host/ClassDriver/MouseHost/makefile
index 748213a1a2a605424b80aba1765bd8608b7d9ca4..7126d6bba4efcea5e1c313ccb5ef41c5257704ce 100644
--- a/Demos/Host/ClassDriver/MouseHost/makefile
+++ b/Demos/Host/ClassDriver/MouseHost/makefile
@@ -79,8 +79,8 @@ BOARD = USBKEY
 #     calculate timings. Do NOT tack on a 'UL' at the end, this will be done
 #     automatically to create a 32-bit value in your source code.
 #
-#     This will be an integer division of F_CLOCK below, as it is sourced by
-#     F_CLOCK after it has run through any CPU prescalers. Note that this value
+#     This will be an integer division of F_USB below, as it is sourced by
+#     F_USB after it has run through any CPU prescalers. Note that this value
 #     does not *change* the processor frequency - it should merely be updated to
 #     reflect the processor speed set externally so that the code can use accurate
 #     software delays.
@@ -88,7 +88,7 @@ F_CPU = 8000000
 
 
 # Input clock frequency.
-#     This will define a symbol, F_CLOCK, in all source code files equal to the
+#     This will define a symbol, F_USB, in all source code files equal to the
 #     input clock frequency (before any prescaling is performed) in Hz. This value may
 #     differ from F_CPU if prescaling is used on the latter, and is required as the
 #     raw input clock is fed directly to the PLL sections of the AVR for high speed
@@ -98,7 +98,7 @@ F_CPU = 8000000
 #
 #     If no clock division is performed on the input clock inside the AVR (via the
 #     CPU clock adjust registers or the clock division fuses), this will be equal to F_CPU.
-F_CLOCK = $(F_CPU)
+F_USB = $(F_CPU)
 
 
 # Output format. (can be srec, ihex, binary)
@@ -179,20 +179,20 @@ CSTANDARD = -std=c99
 
 # Place -D or -U options here for C sources
 CDEFS  = -DF_CPU=$(F_CPU)UL
-CDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CDEFS += -DF_USB=$(F_USB)UL
 CDEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 CDEFS += $(LUFA_OPTS)
 
 
 # Place -D or -U options here for ASM sources
 ADEFS  = -DF_CPU=$(F_CPU)
-ADEFS += -DF_CLOCK=$(F_CLOCK)UL
+ADEFS += -DF_USB=$(F_USB)UL
 ADEFS += -DBOARD=BOARD_$(BOARD)
 ADEFS += $(LUFA_OPTS)
 
 # Place -D or -U options here for C++ sources
 CPPDEFS  = -DF_CPU=$(F_CPU)UL
-CPPDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CPPDEFS += -DF_USB=$(F_USB)UL
 CPPDEFS += -DBOARD=BOARD_$(BOARD)
 CPPDEFS += $(LUFA_OPTS)
 #CPPDEFS += -D__STDC_LIMIT_MACROS
diff --git a/Demos/Host/ClassDriver/MouseHostWithParser/makefile b/Demos/Host/ClassDriver/MouseHostWithParser/makefile
index 040f2697ebf9bb7703a40bb591ea33b0656a2a96..b5fd3cf55a595cbe90349899c639e9c4b76053c4 100644
--- a/Demos/Host/ClassDriver/MouseHostWithParser/makefile
+++ b/Demos/Host/ClassDriver/MouseHostWithParser/makefile
@@ -79,8 +79,8 @@ BOARD = USBKEY
 #     calculate timings. Do NOT tack on a 'UL' at the end, this will be done
 #     automatically to create a 32-bit value in your source code.
 #
-#     This will be an integer division of F_CLOCK below, as it is sourced by
-#     F_CLOCK after it has run through any CPU prescalers. Note that this value
+#     This will be an integer division of F_USB below, as it is sourced by
+#     F_USB after it has run through any CPU prescalers. Note that this value
 #     does not *change* the processor frequency - it should merely be updated to
 #     reflect the processor speed set externally so that the code can use accurate
 #     software delays.
@@ -88,7 +88,7 @@ F_CPU = 8000000
 
 
 # Input clock frequency.
-#     This will define a symbol, F_CLOCK, in all source code files equal to the
+#     This will define a symbol, F_USB, in all source code files equal to the
 #     input clock frequency (before any prescaling is performed) in Hz. This value may
 #     differ from F_CPU if prescaling is used on the latter, and is required as the
 #     raw input clock is fed directly to the PLL sections of the AVR for high speed
@@ -98,7 +98,7 @@ F_CPU = 8000000
 #
 #     If no clock division is performed on the input clock inside the AVR (via the
 #     CPU clock adjust registers or the clock division fuses), this will be equal to F_CPU.
-F_CLOCK = $(F_CPU)
+F_USB = $(F_CPU)
 
 
 # Output format. (can be srec, ihex, binary)
@@ -179,20 +179,20 @@ CSTANDARD = -std=c99
 
 # Place -D or -U options here for C sources
 CDEFS  = -DF_CPU=$(F_CPU)UL
-CDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CDEFS += -DF_USB=$(F_USB)UL
 CDEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 CDEFS += $(LUFA_OPTS)
 
 
 # Place -D or -U options here for ASM sources
 ADEFS  = -DF_CPU=$(F_CPU)
-ADEFS += -DF_CLOCK=$(F_CLOCK)UL
+ADEFS += -DF_USB=$(F_USB)UL
 ADEFS += -DBOARD=BOARD_$(BOARD)
 ADEFS += $(LUFA_OPTS)
 
 # Place -D or -U options here for C++ sources
 CPPDEFS  = -DF_CPU=$(F_CPU)UL
-CPPDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CPPDEFS += -DF_USB=$(F_USB)UL
 CPPDEFS += -DBOARD=BOARD_$(BOARD)
 CPPDEFS += $(LUFA_OPTS)
 #CPPDEFS += -D__STDC_LIMIT_MACROS
diff --git a/Demos/Host/ClassDriver/PrinterHost/makefile b/Demos/Host/ClassDriver/PrinterHost/makefile
index 85638aec5db41d66b5e91ca6f10782fc125a75cc..401f340a9a4902eec255ed86df502a0b16d96eb2 100644
--- a/Demos/Host/ClassDriver/PrinterHost/makefile
+++ b/Demos/Host/ClassDriver/PrinterHost/makefile
@@ -79,8 +79,8 @@ BOARD = USBKEY
 #     calculate timings. Do NOT tack on a 'UL' at the end, this will be done
 #     automatically to create a 32-bit value in your source code.
 #
-#     This will be an integer division of F_CLOCK below, as it is sourced by
-#     F_CLOCK after it has run through any CPU prescalers. Note that this value
+#     This will be an integer division of F_USB below, as it is sourced by
+#     F_USB after it has run through any CPU prescalers. Note that this value
 #     does not *change* the processor frequency - it should merely be updated to
 #     reflect the processor speed set externally so that the code can use accurate
 #     software delays.
@@ -88,7 +88,7 @@ F_CPU = 8000000
 
 
 # Input clock frequency.
-#     This will define a symbol, F_CLOCK, in all source code files equal to the
+#     This will define a symbol, F_USB, in all source code files equal to the
 #     input clock frequency (before any prescaling is performed) in Hz. This value may
 #     differ from F_CPU if prescaling is used on the latter, and is required as the
 #     raw input clock is fed directly to the PLL sections of the AVR for high speed
@@ -98,7 +98,7 @@ F_CPU = 8000000
 #
 #     If no clock division is performed on the input clock inside the AVR (via the
 #     CPU clock adjust registers or the clock division fuses), this will be equal to F_CPU.
-F_CLOCK = $(F_CPU)
+F_USB = $(F_CPU)
 
 
 # Output format. (can be srec, ihex, binary)
@@ -179,20 +179,20 @@ CSTANDARD = -std=c99
 
 # Place -D or -U options here for C sources
 CDEFS  = -DF_CPU=$(F_CPU)UL
-CDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CDEFS += -DF_USB=$(F_USB)UL
 CDEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 CDEFS += $(LUFA_OPTS)
 
 
 # Place -D or -U options here for ASM sources
 ADEFS  = -DF_CPU=$(F_CPU)
-ADEFS += -DF_CLOCK=$(F_CLOCK)UL
+ADEFS += -DF_USB=$(F_USB)UL
 ADEFS += -DBOARD=BOARD_$(BOARD)
 ADEFS += $(LUFA_OPTS)
 
 # Place -D or -U options here for C++ sources
 CPPDEFS  = -DF_CPU=$(F_CPU)UL
-CPPDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CPPDEFS += -DF_USB=$(F_USB)UL
 CPPDEFS += -DBOARD=BOARD_$(BOARD)
 CPPDEFS += $(LUFA_OPTS)
 #CPPDEFS += -D__STDC_LIMIT_MACROS
diff --git a/Demos/Host/ClassDriver/RNDISEthernetHost/makefile b/Demos/Host/ClassDriver/RNDISEthernetHost/makefile
index 9ed8fb08e5e8fe6c9271a3e6190a2eb4f3d30b30..7ebd355bc9c9a90f6f60c6f8c36dbf2cde2861c4 100644
--- a/Demos/Host/ClassDriver/RNDISEthernetHost/makefile
+++ b/Demos/Host/ClassDriver/RNDISEthernetHost/makefile
@@ -79,8 +79,8 @@ BOARD = USBKEY
 #     calculate timings. Do NOT tack on a 'UL' at the end, this will be done
 #     automatically to create a 32-bit value in your source code.
 #
-#     This will be an integer division of F_CLOCK below, as it is sourced by
-#     F_CLOCK after it has run through any CPU prescalers. Note that this value
+#     This will be an integer division of F_USB below, as it is sourced by
+#     F_USB after it has run through any CPU prescalers. Note that this value
 #     does not *change* the processor frequency - it should merely be updated to
 #     reflect the processor speed set externally so that the code can use accurate
 #     software delays.
@@ -88,7 +88,7 @@ F_CPU = 8000000
 
 
 # Input clock frequency.
-#     This will define a symbol, F_CLOCK, in all source code files equal to the
+#     This will define a symbol, F_USB, in all source code files equal to the
 #     input clock frequency (before any prescaling is performed) in Hz. This value may
 #     differ from F_CPU if prescaling is used on the latter, and is required as the
 #     raw input clock is fed directly to the PLL sections of the AVR for high speed
@@ -98,7 +98,7 @@ F_CPU = 8000000
 #
 #     If no clock division is performed on the input clock inside the AVR (via the
 #     CPU clock adjust registers or the clock division fuses), this will be equal to F_CPU.
-F_CLOCK = $(F_CPU)
+F_USB = $(F_CPU)
 
 
 # Output format. (can be srec, ihex, binary)
@@ -179,20 +179,20 @@ CSTANDARD = -std=c99
 
 # Place -D or -U options here for C sources
 CDEFS  = -DF_CPU=$(F_CPU)UL
-CDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CDEFS += -DF_USB=$(F_USB)UL
 CDEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 CDEFS += $(LUFA_OPTS)
 
 
 # Place -D or -U options here for ASM sources
 ADEFS  = -DF_CPU=$(F_CPU)
-ADEFS += -DF_CLOCK=$(F_CLOCK)UL
+ADEFS += -DF_USB=$(F_USB)UL
 ADEFS += -DBOARD=BOARD_$(BOARD)
 ADEFS += $(LUFA_OPTS)
 
 # Place -D or -U options here for C++ sources
 CPPDEFS  = -DF_CPU=$(F_CPU)UL
-CPPDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CPPDEFS += -DF_USB=$(F_USB)UL
 CPPDEFS += -DBOARD=BOARD_$(BOARD)
 CPPDEFS += $(LUFA_OPTS)
 #CPPDEFS += -D__STDC_LIMIT_MACROS
diff --git a/Demos/Host/ClassDriver/StillImageHost/makefile b/Demos/Host/ClassDriver/StillImageHost/makefile
index 1c8a2c38becc286b6bfc82ef4cb095e789d9c469..6969bde81ec2a46cbc531f9b2f1296f621a7e2ee 100644
--- a/Demos/Host/ClassDriver/StillImageHost/makefile
+++ b/Demos/Host/ClassDriver/StillImageHost/makefile
@@ -79,8 +79,8 @@ BOARD = USBKEY
 #     calculate timings. Do NOT tack on a 'UL' at the end, this will be done
 #     automatically to create a 32-bit value in your source code.
 #
-#     This will be an integer division of F_CLOCK below, as it is sourced by
-#     F_CLOCK after it has run through any CPU prescalers. Note that this value
+#     This will be an integer division of F_USB below, as it is sourced by
+#     F_USB after it has run through any CPU prescalers. Note that this value
 #     does not *change* the processor frequency - it should merely be updated to
 #     reflect the processor speed set externally so that the code can use accurate
 #     software delays.
@@ -88,7 +88,7 @@ F_CPU = 8000000
 
 
 # Input clock frequency.
-#     This will define a symbol, F_CLOCK, in all source code files equal to the
+#     This will define a symbol, F_USB, in all source code files equal to the
 #     input clock frequency (before any prescaling is performed) in Hz. This value may
 #     differ from F_CPU if prescaling is used on the latter, and is required as the
 #     raw input clock is fed directly to the PLL sections of the AVR for high speed
@@ -98,7 +98,7 @@ F_CPU = 8000000
 #
 #     If no clock division is performed on the input clock inside the AVR (via the
 #     CPU clock adjust registers or the clock division fuses), this will be equal to F_CPU.
-F_CLOCK = $(F_CPU)
+F_USB = $(F_CPU)
 
 
 # Output format. (can be srec, ihex, binary)
@@ -179,20 +179,20 @@ CSTANDARD = -std=c99
 
 # Place -D or -U options here for C sources
 CDEFS  = -DF_CPU=$(F_CPU)UL
-CDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CDEFS += -DF_USB=$(F_USB)UL
 CDEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 CDEFS += $(LUFA_OPTS)
 
 
 # Place -D or -U options here for ASM sources
 ADEFS  = -DF_CPU=$(F_CPU)
-ADEFS += -DF_CLOCK=$(F_CLOCK)UL
+ADEFS += -DF_USB=$(F_USB)UL
 ADEFS += -DBOARD=BOARD_$(BOARD)
 ADEFS += $(LUFA_OPTS)
 
 # Place -D or -U options here for C++ sources
 CPPDEFS  = -DF_CPU=$(F_CPU)UL
-CPPDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CPPDEFS += -DF_USB=$(F_USB)UL
 CPPDEFS += -DBOARD=BOARD_$(BOARD)
 CPPDEFS += $(LUFA_OPTS)
 #CPPDEFS += -D__STDC_LIMIT_MACROS
diff --git a/Demos/Host/ClassDriver/VirtualSerialHost/makefile b/Demos/Host/ClassDriver/VirtualSerialHost/makefile
index 176e1fabf96f2d69120d2390557ed3b97cb126f9..45da06f16101ac248a02d471a14710b2963f9e40 100644
--- a/Demos/Host/ClassDriver/VirtualSerialHost/makefile
+++ b/Demos/Host/ClassDriver/VirtualSerialHost/makefile
@@ -79,8 +79,8 @@ BOARD = USBKEY
 #     calculate timings. Do NOT tack on a 'UL' at the end, this will be done
 #     automatically to create a 32-bit value in your source code.
 #
-#     This will be an integer division of F_CLOCK below, as it is sourced by
-#     F_CLOCK after it has run through any CPU prescalers. Note that this value
+#     This will be an integer division of F_USB below, as it is sourced by
+#     F_USB after it has run through any CPU prescalers. Note that this value
 #     does not *change* the processor frequency - it should merely be updated to
 #     reflect the processor speed set externally so that the code can use accurate
 #     software delays.
@@ -88,7 +88,7 @@ F_CPU = 8000000
 
 
 # Input clock frequency.
-#     This will define a symbol, F_CLOCK, in all source code files equal to the
+#     This will define a symbol, F_USB, in all source code files equal to the
 #     input clock frequency (before any prescaling is performed) in Hz. This value may
 #     differ from F_CPU if prescaling is used on the latter, and is required as the
 #     raw input clock is fed directly to the PLL sections of the AVR for high speed
@@ -98,7 +98,7 @@ F_CPU = 8000000
 #
 #     If no clock division is performed on the input clock inside the AVR (via the
 #     CPU clock adjust registers or the clock division fuses), this will be equal to F_CPU.
-F_CLOCK = $(F_CPU)
+F_USB = $(F_CPU)
 
 
 # Output format. (can be srec, ihex, binary)
@@ -179,20 +179,20 @@ CSTANDARD = -std=c99
 
 # Place -D or -U options here for C sources
 CDEFS  = -DF_CPU=$(F_CPU)UL
-CDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CDEFS += -DF_USB=$(F_USB)UL
 CDEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 CDEFS += $(LUFA_OPTS)
 
 
 # Place -D or -U options here for ASM sources
 ADEFS  = -DF_CPU=$(F_CPU)
-ADEFS += -DF_CLOCK=$(F_CLOCK)UL
+ADEFS += -DF_USB=$(F_USB)UL
 ADEFS += -DBOARD=BOARD_$(BOARD)
 ADEFS += $(LUFA_OPTS)
 
 # Place -D or -U options here for C++ sources
 CPPDEFS  = -DF_CPU=$(F_CPU)UL
-CPPDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CPPDEFS += -DF_USB=$(F_USB)UL
 CPPDEFS += -DBOARD=BOARD_$(BOARD)
 CPPDEFS += $(LUFA_OPTS)
 #CPPDEFS += -D__STDC_LIMIT_MACROS
diff --git a/Demos/Host/Incomplete/BluetoothHost/makefile b/Demos/Host/Incomplete/BluetoothHost/makefile
index 1c6dc0d874c0e78fce431dfb3af2618812d98eb1..c1f83c11ee2eb28ad98dc8cd902a424757a356fc 100644
--- a/Demos/Host/Incomplete/BluetoothHost/makefile
+++ b/Demos/Host/Incomplete/BluetoothHost/makefile
@@ -79,8 +79,8 @@ BOARD = USBKEY
 #     calculate timings. Do NOT tack on a 'UL' at the end, this will be done
 #     automatically to create a 32-bit value in your source code.
 #
-#     This will be an integer division of F_CLOCK below, as it is sourced by
-#     F_CLOCK after it has run through any CPU prescalers. Note that this value
+#     This will be an integer division of F_USB below, as it is sourced by
+#     F_USB after it has run through any CPU prescalers. Note that this value
 #     does not *change* the processor frequency - it should merely be updated to
 #     reflect the processor speed set externally so that the code can use accurate
 #     software delays.
@@ -88,7 +88,7 @@ F_CPU = 8000000
 
 
 # Input clock frequency.
-#     This will define a symbol, F_CLOCK, in all source code files equal to the
+#     This will define a symbol, F_USB, in all source code files equal to the
 #     input clock frequency (before any prescaling is performed) in Hz. This value may
 #     differ from F_CPU if prescaling is used on the latter, and is required as the
 #     raw input clock is fed directly to the PLL sections of the AVR for high speed
@@ -98,7 +98,7 @@ F_CPU = 8000000
 #
 #     If no clock division is performed on the input clock inside the AVR (via the
 #     CPU clock adjust registers or the clock division fuses), this will be equal to F_CPU.
-F_CLOCK = $(F_CPU)
+F_USB = $(F_CPU)
 
 
 # Output format. (can be srec, ihex, binary)
@@ -188,20 +188,20 @@ CSTANDARD = -std=c99
 
 # Place -D or -U options here for C sources
 CDEFS  = -DF_CPU=$(F_CPU)UL
-CDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CDEFS += -DF_USB=$(F_USB)UL
 CDEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 CDEFS += $(LUFA_OPTS)
 
 
 # Place -D or -U options here for ASM sources
 ADEFS  = -DF_CPU=$(F_CPU)
-ADEFS += -DF_CLOCK=$(F_CLOCK)UL
+ADEFS += -DF_USB=$(F_USB)UL
 ADEFS += -DBOARD=BOARD_$(BOARD)
 ADEFS += $(LUFA_OPTS)
 
 # Place -D or -U options here for C++ sources
 CPPDEFS  = -DF_CPU=$(F_CPU)UL
-CPPDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CPPDEFS += -DF_USB=$(F_USB)UL
 CPPDEFS += -DBOARD=BOARD_$(BOARD)
 CPPDEFS += $(LUFA_OPTS)
 #CPPDEFS += -D__STDC_LIMIT_MACROS
diff --git a/Demos/Host/LowLevel/GenericHIDHost/makefile b/Demos/Host/LowLevel/GenericHIDHost/makefile
index 936538496f6055958025334a94f16bc67926a466..3c791d242b3f5998630ad1530c6eb59326f066e4 100644
--- a/Demos/Host/LowLevel/GenericHIDHost/makefile
+++ b/Demos/Host/LowLevel/GenericHIDHost/makefile
@@ -79,8 +79,8 @@ BOARD = USBKEY
 #     calculate timings. Do NOT tack on a 'UL' at the end, this will be done
 #     automatically to create a 32-bit value in your source code.
 #
-#     This will be an integer division of F_CLOCK below, as it is sourced by
-#     F_CLOCK after it has run through any CPU prescalers. Note that this value
+#     This will be an integer division of F_USB below, as it is sourced by
+#     F_USB after it has run through any CPU prescalers. Note that this value
 #     does not *change* the processor frequency - it should merely be updated to
 #     reflect the processor speed set externally so that the code can use accurate
 #     software delays.
@@ -88,7 +88,7 @@ F_CPU = 8000000
 
 
 # Input clock frequency.
-#     This will define a symbol, F_CLOCK, in all source code files equal to the
+#     This will define a symbol, F_USB, in all source code files equal to the
 #     input clock frequency (before any prescaling is performed) in Hz. This value may
 #     differ from F_CPU if prescaling is used on the latter, and is required as the
 #     raw input clock is fed directly to the PLL sections of the AVR for high speed
@@ -98,7 +98,7 @@ F_CPU = 8000000
 #
 #     If no clock division is performed on the input clock inside the AVR (via the
 #     CPU clock adjust registers or the clock division fuses), this will be equal to F_CPU.
-F_CLOCK = $(F_CPU)
+F_USB = $(F_CPU)
 
 
 # Output format. (can be srec, ihex, binary)
@@ -179,20 +179,20 @@ CSTANDARD = -std=c99
 
 # Place -D or -U options here for C sources
 CDEFS  = -DF_CPU=$(F_CPU)UL
-CDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CDEFS += -DF_USB=$(F_USB)UL
 CDEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 CDEFS += $(LUFA_OPTS)
 
 
 # Place -D or -U options here for ASM sources
 ADEFS  = -DF_CPU=$(F_CPU)
-ADEFS += -DF_CLOCK=$(F_CLOCK)UL
+ADEFS += -DF_USB=$(F_USB)UL
 ADEFS += -DBOARD=BOARD_$(BOARD)
 ADEFS += $(LUFA_OPTS)
 
 # Place -D or -U options here for C++ sources
 CPPDEFS  = -DF_CPU=$(F_CPU)UL
-CPPDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CPPDEFS += -DF_USB=$(F_USB)UL
 CPPDEFS += -DBOARD=BOARD_$(BOARD)
 CPPDEFS += $(LUFA_OPTS)
 #CPPDEFS += -D__STDC_LIMIT_MACROS
diff --git a/Demos/Host/LowLevel/JoystickHostWithParser/makefile b/Demos/Host/LowLevel/JoystickHostWithParser/makefile
index 09f87d980255397d7573bb9fe068a38735f7006c..730c953c622e420ffbf7d5c3626ace971692f16d 100644
--- a/Demos/Host/LowLevel/JoystickHostWithParser/makefile
+++ b/Demos/Host/LowLevel/JoystickHostWithParser/makefile
@@ -79,8 +79,8 @@ BOARD = USBKEY
 #     calculate timings. Do NOT tack on a 'UL' at the end, this will be done
 #     automatically to create a 32-bit value in your source code.
 #
-#     This will be an integer division of F_CLOCK below, as it is sourced by
-#     F_CLOCK after it has run through any CPU prescalers. Note that this value
+#     This will be an integer division of F_USB below, as it is sourced by
+#     F_USB after it has run through any CPU prescalers. Note that this value
 #     does not *change* the processor frequency - it should merely be updated to
 #     reflect the processor speed set externally so that the code can use accurate
 #     software delays.
@@ -88,7 +88,7 @@ F_CPU = 8000000
 
 
 # Input clock frequency.
-#     This will define a symbol, F_CLOCK, in all source code files equal to the
+#     This will define a symbol, F_USB, in all source code files equal to the
 #     input clock frequency (before any prescaling is performed) in Hz. This value may
 #     differ from F_CPU if prescaling is used on the latter, and is required as the
 #     raw input clock is fed directly to the PLL sections of the AVR for high speed
@@ -98,7 +98,7 @@ F_CPU = 8000000
 #
 #     If no clock division is performed on the input clock inside the AVR (via the
 #     CPU clock adjust registers or the clock division fuses), this will be equal to F_CPU.
-F_CLOCK = $(F_CPU)
+F_USB = $(F_CPU)
 
 
 # Output format. (can be srec, ihex, binary)
@@ -180,20 +180,20 @@ CSTANDARD = -std=c99
 
 # Place -D or -U options here for C sources
 CDEFS  = -DF_CPU=$(F_CPU)UL
-CDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CDEFS += -DF_USB=$(F_USB)UL
 CDEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 CDEFS += $(LUFA_OPTS)
 
 
 # Place -D or -U options here for ASM sources
 ADEFS  = -DF_CPU=$(F_CPU)
-ADEFS += -DF_CLOCK=$(F_CLOCK)UL
+ADEFS += -DF_USB=$(F_USB)UL
 ADEFS += -DBOARD=BOARD_$(BOARD)
 ADEFS += $(LUFA_OPTS)
 
 # Place -D or -U options here for C++ sources
 CPPDEFS  = -DF_CPU=$(F_CPU)UL
-CPPDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CPPDEFS += -DF_USB=$(F_USB)UL
 CPPDEFS += -DBOARD=BOARD_$(BOARD)
 CPPDEFS += $(LUFA_OPTS)
 #CPPDEFS += -D__STDC_LIMIT_MACROS
diff --git a/Demos/Host/LowLevel/KeyboardHost/makefile b/Demos/Host/LowLevel/KeyboardHost/makefile
index a4b16f1dba79ce27b99c0b4e82cd3dd6fb36ed3e..0f2912f3b58ccabb8b1d1743c3a46a6b531f0671 100644
--- a/Demos/Host/LowLevel/KeyboardHost/makefile
+++ b/Demos/Host/LowLevel/KeyboardHost/makefile
@@ -79,8 +79,8 @@ BOARD = USBKEY
 #     calculate timings. Do NOT tack on a 'UL' at the end, this will be done
 #     automatically to create a 32-bit value in your source code.
 #
-#     This will be an integer division of F_CLOCK below, as it is sourced by
-#     F_CLOCK after it has run through any CPU prescalers. Note that this value
+#     This will be an integer division of F_USB below, as it is sourced by
+#     F_USB after it has run through any CPU prescalers. Note that this value
 #     does not *change* the processor frequency - it should merely be updated to
 #     reflect the processor speed set externally so that the code can use accurate
 #     software delays.
@@ -88,7 +88,7 @@ F_CPU = 8000000
 
 
 # Input clock frequency.
-#     This will define a symbol, F_CLOCK, in all source code files equal to the
+#     This will define a symbol, F_USB, in all source code files equal to the
 #     input clock frequency (before any prescaling is performed) in Hz. This value may
 #     differ from F_CPU if prescaling is used on the latter, and is required as the
 #     raw input clock is fed directly to the PLL sections of the AVR for high speed
@@ -98,7 +98,7 @@ F_CPU = 8000000
 #
 #     If no clock division is performed on the input clock inside the AVR (via the
 #     CPU clock adjust registers or the clock division fuses), this will be equal to F_CPU.
-F_CLOCK = $(F_CPU)
+F_USB = $(F_CPU)
 
 
 # Output format. (can be srec, ihex, binary)
@@ -179,20 +179,20 @@ CSTANDARD = -std=c99
 
 # Place -D or -U options here for C sources
 CDEFS  = -DF_CPU=$(F_CPU)UL
-CDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CDEFS += -DF_USB=$(F_USB)UL
 CDEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 CDEFS += $(LUFA_OPTS)
 
 
 # Place -D or -U options here for ASM sources
 ADEFS  = -DF_CPU=$(F_CPU)
-ADEFS += -DF_CLOCK=$(F_CLOCK)UL
+ADEFS += -DF_USB=$(F_USB)UL
 ADEFS += -DBOARD=BOARD_$(BOARD)
 ADEFS += $(LUFA_OPTS)
 
 # Place -D or -U options here for C++ sources
 CPPDEFS  = -DF_CPU=$(F_CPU)UL
-CPPDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CPPDEFS += -DF_USB=$(F_USB)UL
 CPPDEFS += -DBOARD=BOARD_$(BOARD)
 CPPDEFS += $(LUFA_OPTS)
 #CPPDEFS += -D__STDC_LIMIT_MACROS
diff --git a/Demos/Host/LowLevel/KeyboardHostWithParser/makefile b/Demos/Host/LowLevel/KeyboardHostWithParser/makefile
index 9ddad4e9b88a243d26e6b38a0119db43cefde6d0..e391fdba51a0685a67676cacb26797239f9dffe4 100644
--- a/Demos/Host/LowLevel/KeyboardHostWithParser/makefile
+++ b/Demos/Host/LowLevel/KeyboardHostWithParser/makefile
@@ -79,8 +79,8 @@ BOARD = USBKEY
 #     calculate timings. Do NOT tack on a 'UL' at the end, this will be done
 #     automatically to create a 32-bit value in your source code.
 #
-#     This will be an integer division of F_CLOCK below, as it is sourced by
-#     F_CLOCK after it has run through any CPU prescalers. Note that this value
+#     This will be an integer division of F_USB below, as it is sourced by
+#     F_USB after it has run through any CPU prescalers. Note that this value
 #     does not *change* the processor frequency - it should merely be updated to
 #     reflect the processor speed set externally so that the code can use accurate
 #     software delays.
@@ -88,7 +88,7 @@ F_CPU = 8000000
 
 
 # Input clock frequency.
-#     This will define a symbol, F_CLOCK, in all source code files equal to the
+#     This will define a symbol, F_USB, in all source code files equal to the
 #     input clock frequency (before any prescaling is performed) in Hz. This value may
 #     differ from F_CPU if prescaling is used on the latter, and is required as the
 #     raw input clock is fed directly to the PLL sections of the AVR for high speed
@@ -98,7 +98,7 @@ F_CPU = 8000000
 #
 #     If no clock division is performed on the input clock inside the AVR (via the
 #     CPU clock adjust registers or the clock division fuses), this will be equal to F_CPU.
-F_CLOCK = $(F_CPU)
+F_USB = $(F_CPU)
 
 
 # Output format. (can be srec, ihex, binary)
@@ -180,20 +180,20 @@ CSTANDARD = -std=c99
 
 # Place -D or -U options here for C sources
 CDEFS  = -DF_CPU=$(F_CPU)UL
-CDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CDEFS += -DF_USB=$(F_USB)UL
 CDEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 CDEFS += $(LUFA_OPTS)
 
 
 # Place -D or -U options here for ASM sources
 ADEFS  = -DF_CPU=$(F_CPU)
-ADEFS += -DF_CLOCK=$(F_CLOCK)UL
+ADEFS += -DF_USB=$(F_USB)UL
 ADEFS += -DBOARD=BOARD_$(BOARD)
 ADEFS += $(LUFA_OPTS)
 
 # Place -D or -U options here for C++ sources
 CPPDEFS  = -DF_CPU=$(F_CPU)UL
-CPPDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CPPDEFS += -DF_USB=$(F_USB)UL
 CPPDEFS += -DBOARD=BOARD_$(BOARD)
 CPPDEFS += $(LUFA_OPTS)
 #CPPDEFS += -D__STDC_LIMIT_MACROS
diff --git a/Demos/Host/LowLevel/MIDIHost/makefile b/Demos/Host/LowLevel/MIDIHost/makefile
index 2f304753a726b0721f5f787a7adaf956863d5f33..a84d1b4f486d51d0cd825cdfb1ef74d98b35f371 100644
--- a/Demos/Host/LowLevel/MIDIHost/makefile
+++ b/Demos/Host/LowLevel/MIDIHost/makefile
@@ -79,8 +79,8 @@ BOARD = USBKEY
 #     calculate timings. Do NOT tack on a 'UL' at the end, this will be done
 #     automatically to create a 32-bit value in your source code.
 #
-#     This will be an integer division of F_CLOCK below, as it is sourced by
-#     F_CLOCK after it has run through any CPU prescalers. Note that this value
+#     This will be an integer division of F_USB below, as it is sourced by
+#     F_USB after it has run through any CPU prescalers. Note that this value
 #     does not *change* the processor frequency - it should merely be updated to
 #     reflect the processor speed set externally so that the code can use accurate
 #     software delays.
@@ -88,7 +88,7 @@ F_CPU = 8000000
 
 
 # Input clock frequency.
-#     This will define a symbol, F_CLOCK, in all source code files equal to the
+#     This will define a symbol, F_USB, in all source code files equal to the
 #     input clock frequency (before any prescaling is performed) in Hz. This value may
 #     differ from F_CPU if prescaling is used on the latter, and is required as the
 #     raw input clock is fed directly to the PLL sections of the AVR for high speed
@@ -98,7 +98,7 @@ F_CPU = 8000000
 #
 #     If no clock division is performed on the input clock inside the AVR (via the
 #     CPU clock adjust registers or the clock division fuses), this will be equal to F_CPU.
-F_CLOCK = $(F_CPU)
+F_USB = $(F_CPU)
 
 
 # Output format. (can be srec, ihex, binary)
@@ -179,20 +179,20 @@ CSTANDARD = -std=c99
 
 # Place -D or -U options here for C sources
 CDEFS  = -DF_CPU=$(F_CPU)UL
-CDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CDEFS += -DF_USB=$(F_USB)UL
 CDEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 CDEFS += $(LUFA_OPTS)
 
 
 # Place -D or -U options here for ASM sources
 ADEFS  = -DF_CPU=$(F_CPU)
-ADEFS += -DF_CLOCK=$(F_CLOCK)UL
+ADEFS += -DF_USB=$(F_USB)UL
 ADEFS += -DBOARD=BOARD_$(BOARD)
 ADEFS += $(LUFA_OPTS)
 
 # Place -D or -U options here for C++ sources
 CPPDEFS  = -DF_CPU=$(F_CPU)UL
-CPPDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CPPDEFS += -DF_USB=$(F_USB)UL
 CPPDEFS += -DBOARD=BOARD_$(BOARD)
 CPPDEFS += $(LUFA_OPTS)
 #CPPDEFS += -D__STDC_LIMIT_MACROS
diff --git a/Demos/Host/LowLevel/MassStorageHost/makefile b/Demos/Host/LowLevel/MassStorageHost/makefile
index 756204ae9edac4dfd2879df2c93a93c03c85221f..b2a7478bed60782ba3ca5baf3a26247508bd6e15 100644
--- a/Demos/Host/LowLevel/MassStorageHost/makefile
+++ b/Demos/Host/LowLevel/MassStorageHost/makefile
@@ -79,8 +79,8 @@ BOARD = USBKEY
 #     calculate timings. Do NOT tack on a 'UL' at the end, this will be done
 #     automatically to create a 32-bit value in your source code.
 #
-#     This will be an integer division of F_CLOCK below, as it is sourced by
-#     F_CLOCK after it has run through any CPU prescalers. Note that this value
+#     This will be an integer division of F_USB below, as it is sourced by
+#     F_USB after it has run through any CPU prescalers. Note that this value
 #     does not *change* the processor frequency - it should merely be updated to
 #     reflect the processor speed set externally so that the code can use accurate
 #     software delays.
@@ -88,7 +88,7 @@ F_CPU = 8000000
 
 
 # Input clock frequency.
-#     This will define a symbol, F_CLOCK, in all source code files equal to the
+#     This will define a symbol, F_USB, in all source code files equal to the
 #     input clock frequency (before any prescaling is performed) in Hz. This value may
 #     differ from F_CPU if prescaling is used on the latter, and is required as the
 #     raw input clock is fed directly to the PLL sections of the AVR for high speed
@@ -98,7 +98,7 @@ F_CPU = 8000000
 #
 #     If no clock division is performed on the input clock inside the AVR (via the
 #     CPU clock adjust registers or the clock division fuses), this will be equal to F_CPU.
-F_CLOCK = $(F_CPU)
+F_USB = $(F_CPU)
 
 
 # Output format. (can be srec, ihex, binary)
@@ -181,20 +181,20 @@ CSTANDARD = -std=c99
 
 # Place -D or -U options here for C sources
 CDEFS  = -DF_CPU=$(F_CPU)UL
-CDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CDEFS += -DF_USB=$(F_USB)UL
 CDEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 CDEFS += $(LUFA_OPTS)
 
 
 # Place -D or -U options here for ASM sources
 ADEFS  = -DF_CPU=$(F_CPU)
-ADEFS += -DF_CLOCK=$(F_CLOCK)UL
+ADEFS += -DF_USB=$(F_USB)UL
 ADEFS += -DBOARD=BOARD_$(BOARD)
 ADEFS += $(LUFA_OPTS)
 
 # Place -D or -U options here for C++ sources
 CPPDEFS  = -DF_CPU=$(F_CPU)UL
-CPPDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CPPDEFS += -DF_USB=$(F_USB)UL
 CPPDEFS += -DBOARD=BOARD_$(BOARD)
 CPPDEFS += $(LUFA_OPTS)
 #CPPDEFS += -D__STDC_LIMIT_MACROS
diff --git a/Demos/Host/LowLevel/MouseHost/makefile b/Demos/Host/LowLevel/MouseHost/makefile
index e0abc3fde107f7ba3319582c9b14a48e6428c69e..61e162d123f5e7592445f4c32a951b6eefe6935e 100644
--- a/Demos/Host/LowLevel/MouseHost/makefile
+++ b/Demos/Host/LowLevel/MouseHost/makefile
@@ -79,8 +79,8 @@ BOARD = USBKEY
 #     calculate timings. Do NOT tack on a 'UL' at the end, this will be done
 #     automatically to create a 32-bit value in your source code.
 #
-#     This will be an integer division of F_CLOCK below, as it is sourced by
-#     F_CLOCK after it has run through any CPU prescalers. Note that this value
+#     This will be an integer division of F_USB below, as it is sourced by
+#     F_USB after it has run through any CPU prescalers. Note that this value
 #     does not *change* the processor frequency - it should merely be updated to
 #     reflect the processor speed set externally so that the code can use accurate
 #     software delays.
@@ -88,7 +88,7 @@ F_CPU = 8000000
 
 
 # Input clock frequency.
-#     This will define a symbol, F_CLOCK, in all source code files equal to the
+#     This will define a symbol, F_USB, in all source code files equal to the
 #     input clock frequency (before any prescaling is performed) in Hz. This value may
 #     differ from F_CPU if prescaling is used on the latter, and is required as the
 #     raw input clock is fed directly to the PLL sections of the AVR for high speed
@@ -98,7 +98,7 @@ F_CPU = 8000000
 #
 #     If no clock division is performed on the input clock inside the AVR (via the
 #     CPU clock adjust registers or the clock division fuses), this will be equal to F_CPU.
-F_CLOCK = $(F_CPU)
+F_USB = $(F_CPU)
 
 
 # Output format. (can be srec, ihex, binary)
@@ -179,20 +179,20 @@ CSTANDARD = -std=c99
 
 # Place -D or -U options here for C sources
 CDEFS  = -DF_CPU=$(F_CPU)UL
-CDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CDEFS += -DF_USB=$(F_USB)UL
 CDEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 CDEFS += $(LUFA_OPTS)
 
 
 # Place -D or -U options here for ASM sources
 ADEFS  = -DF_CPU=$(F_CPU)
-ADEFS += -DF_CLOCK=$(F_CLOCK)UL
+ADEFS += -DF_USB=$(F_USB)UL
 ADEFS += -DBOARD=BOARD_$(BOARD)
 ADEFS += $(LUFA_OPTS)
 
 # Place -D or -U options here for C++ sources
 CPPDEFS  = -DF_CPU=$(F_CPU)UL
-CPPDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CPPDEFS += -DF_USB=$(F_USB)UL
 CPPDEFS += -DBOARD=BOARD_$(BOARD)
 CPPDEFS += $(LUFA_OPTS)
 #CPPDEFS += -D__STDC_LIMIT_MACROS
diff --git a/Demos/Host/LowLevel/MouseHostWithParser/makefile b/Demos/Host/LowLevel/MouseHostWithParser/makefile
index 40648eecec5b97ce0eb4ba99741d214cd59eb78a..a4ce7bcb56205d152f596f9a253feaf4857a5cdb 100644
--- a/Demos/Host/LowLevel/MouseHostWithParser/makefile
+++ b/Demos/Host/LowLevel/MouseHostWithParser/makefile
@@ -79,8 +79,8 @@ BOARD = USBKEY
 #     calculate timings. Do NOT tack on a 'UL' at the end, this will be done
 #     automatically to create a 32-bit value in your source code.
 #
-#     This will be an integer division of F_CLOCK below, as it is sourced by
-#     F_CLOCK after it has run through any CPU prescalers. Note that this value
+#     This will be an integer division of F_USB below, as it is sourced by
+#     F_USB after it has run through any CPU prescalers. Note that this value
 #     does not *change* the processor frequency - it should merely be updated to
 #     reflect the processor speed set externally so that the code can use accurate
 #     software delays.
@@ -88,7 +88,7 @@ F_CPU = 8000000
 
 
 # Input clock frequency.
-#     This will define a symbol, F_CLOCK, in all source code files equal to the
+#     This will define a symbol, F_USB, in all source code files equal to the
 #     input clock frequency (before any prescaling is performed) in Hz. This value may
 #     differ from F_CPU if prescaling is used on the latter, and is required as the
 #     raw input clock is fed directly to the PLL sections of the AVR for high speed
@@ -98,7 +98,7 @@ F_CPU = 8000000
 #
 #     If no clock division is performed on the input clock inside the AVR (via the
 #     CPU clock adjust registers or the clock division fuses), this will be equal to F_CPU.
-F_CLOCK = $(F_CPU)
+F_USB = $(F_CPU)
 
 
 # Output format. (can be srec, ihex, binary)
@@ -180,20 +180,20 @@ CSTANDARD = -std=c99
 
 # Place -D or -U options here for C sources
 CDEFS  = -DF_CPU=$(F_CPU)UL
-CDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CDEFS += -DF_USB=$(F_USB)UL
 CDEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 CDEFS += $(LUFA_OPTS)
 
 
 # Place -D or -U options here for ASM sources
 ADEFS  = -DF_CPU=$(F_CPU)
-ADEFS += -DF_CLOCK=$(F_CLOCK)UL
+ADEFS += -DF_USB=$(F_USB)UL
 ADEFS += -DBOARD=BOARD_$(BOARD)
 ADEFS += $(LUFA_OPTS)
 
 # Place -D or -U options here for C++ sources
 CPPDEFS  = -DF_CPU=$(F_CPU)UL
-CPPDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CPPDEFS += -DF_USB=$(F_USB)UL
 CPPDEFS += -DBOARD=BOARD_$(BOARD)
 CPPDEFS += $(LUFA_OPTS)
 #CPPDEFS += -D__STDC_LIMIT_MACROS
diff --git a/Demos/Host/LowLevel/PrinterHost/makefile b/Demos/Host/LowLevel/PrinterHost/makefile
index 374159062b236db7f49c6495a542323a2484767d..249c67b56e7af77deca109fc0202121dbd544f9c 100644
--- a/Demos/Host/LowLevel/PrinterHost/makefile
+++ b/Demos/Host/LowLevel/PrinterHost/makefile
@@ -79,8 +79,8 @@ BOARD = USBKEY
 #     calculate timings. Do NOT tack on a 'UL' at the end, this will be done
 #     automatically to create a 32-bit value in your source code.
 #
-#     This will be an integer division of F_CLOCK below, as it is sourced by
-#     F_CLOCK after it has run through any CPU prescalers. Note that this value
+#     This will be an integer division of F_USB below, as it is sourced by
+#     F_USB after it has run through any CPU prescalers. Note that this value
 #     does not *change* the processor frequency - it should merely be updated to
 #     reflect the processor speed set externally so that the code can use accurate
 #     software delays.
@@ -88,7 +88,7 @@ F_CPU = 8000000
 
 
 # Input clock frequency.
-#     This will define a symbol, F_CLOCK, in all source code files equal to the
+#     This will define a symbol, F_USB, in all source code files equal to the
 #     input clock frequency (before any prescaling is performed) in Hz. This value may
 #     differ from F_CPU if prescaling is used on the latter, and is required as the
 #     raw input clock is fed directly to the PLL sections of the AVR for high speed
@@ -98,7 +98,7 @@ F_CPU = 8000000
 #
 #     If no clock division is performed on the input clock inside the AVR (via the
 #     CPU clock adjust registers or the clock division fuses), this will be equal to F_CPU.
-F_CLOCK = $(F_CPU)
+F_USB = $(F_CPU)
 
 
 # Output format. (can be srec, ihex, binary)
@@ -180,20 +180,20 @@ CSTANDARD = -std=c99
 
 # Place -D or -U options here for C sources
 CDEFS  = -DF_CPU=$(F_CPU)UL
-CDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CDEFS += -DF_USB=$(F_USB)UL
 CDEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 CDEFS += $(LUFA_OPTS)
 
 
 # Place -D or -U options here for ASM sources
 ADEFS  = -DF_CPU=$(F_CPU)
-ADEFS += -DF_CLOCK=$(F_CLOCK)UL
+ADEFS += -DF_USB=$(F_USB)UL
 ADEFS += -DBOARD=BOARD_$(BOARD)
 ADEFS += $(LUFA_OPTS)
 
 # Place -D or -U options here for C++ sources
 CPPDEFS  = -DF_CPU=$(F_CPU)UL
-CPPDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CPPDEFS += -DF_USB=$(F_USB)UL
 CPPDEFS += -DBOARD=BOARD_$(BOARD)
 CPPDEFS += $(LUFA_OPTS)
 #CPPDEFS += -D__STDC_LIMIT_MACROS
diff --git a/Demos/Host/LowLevel/RNDISEthernetHost/makefile b/Demos/Host/LowLevel/RNDISEthernetHost/makefile
index 5f0e12b73fde9fbd5150a9e9998a80f21730e0c9..1d21b8ef1b422334a83578e0ea9d2cc7612eb4bc 100644
--- a/Demos/Host/LowLevel/RNDISEthernetHost/makefile
+++ b/Demos/Host/LowLevel/RNDISEthernetHost/makefile
@@ -79,8 +79,8 @@ BOARD = USBKEY
 #     calculate timings. Do NOT tack on a 'UL' at the end, this will be done
 #     automatically to create a 32-bit value in your source code.
 #
-#     This will be an integer division of F_CLOCK below, as it is sourced by
-#     F_CLOCK after it has run through any CPU prescalers. Note that this value
+#     This will be an integer division of F_USB below, as it is sourced by
+#     F_USB after it has run through any CPU prescalers. Note that this value
 #     does not *change* the processor frequency - it should merely be updated to
 #     reflect the processor speed set externally so that the code can use accurate
 #     software delays.
@@ -88,7 +88,7 @@ F_CPU = 8000000
 
 
 # Input clock frequency.
-#     This will define a symbol, F_CLOCK, in all source code files equal to the
+#     This will define a symbol, F_USB, in all source code files equal to the
 #     input clock frequency (before any prescaling is performed) in Hz. This value may
 #     differ from F_CPU if prescaling is used on the latter, and is required as the
 #     raw input clock is fed directly to the PLL sections of the AVR for high speed
@@ -98,7 +98,7 @@ F_CPU = 8000000
 #
 #     If no clock division is performed on the input clock inside the AVR (via the
 #     CPU clock adjust registers or the clock division fuses), this will be equal to F_CPU.
-F_CLOCK = $(F_CPU)
+F_USB = $(F_CPU)
 
 
 # Output format. (can be srec, ihex, binary)
@@ -180,20 +180,20 @@ CSTANDARD = -std=c99
 
 # Place -D or -U options here for C sources
 CDEFS  = -DF_CPU=$(F_CPU)UL
-CDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CDEFS += -DF_USB=$(F_USB)UL
 CDEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 CDEFS += $(LUFA_OPTS)
 
 
 # Place -D or -U options here for ASM sources
 ADEFS  = -DF_CPU=$(F_CPU)
-ADEFS += -DF_CLOCK=$(F_CLOCK)UL
+ADEFS += -DF_USB=$(F_USB)UL
 ADEFS += -DBOARD=BOARD_$(BOARD)
 ADEFS += $(LUFA_OPTS)
 
 # Place -D or -U options here for C++ sources
 CPPDEFS  = -DF_CPU=$(F_CPU)UL
-CPPDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CPPDEFS += -DF_USB=$(F_USB)UL
 CPPDEFS += -DBOARD=BOARD_$(BOARD)
 CPPDEFS += $(LUFA_OPTS)
 #CPPDEFS += -D__STDC_LIMIT_MACROS
diff --git a/Demos/Host/LowLevel/StillImageHost/makefile b/Demos/Host/LowLevel/StillImageHost/makefile
index 5878b586ae9a6f09567047c69262d0bf1e9c4dfb..912313e379131d9c8ba5a0e38ac79c306971fd53 100644
--- a/Demos/Host/LowLevel/StillImageHost/makefile
+++ b/Demos/Host/LowLevel/StillImageHost/makefile
@@ -79,8 +79,8 @@ BOARD = USBKEY
 #     calculate timings. Do NOT tack on a 'UL' at the end, this will be done
 #     automatically to create a 32-bit value in your source code.
 #
-#     This will be an integer division of F_CLOCK below, as it is sourced by
-#     F_CLOCK after it has run through any CPU prescalers. Note that this value
+#     This will be an integer division of F_USB below, as it is sourced by
+#     F_USB after it has run through any CPU prescalers. Note that this value
 #     does not *change* the processor frequency - it should merely be updated to
 #     reflect the processor speed set externally so that the code can use accurate
 #     software delays.
@@ -88,7 +88,7 @@ F_CPU = 8000000
 
 
 # Input clock frequency.
-#     This will define a symbol, F_CLOCK, in all source code files equal to the
+#     This will define a symbol, F_USB, in all source code files equal to the
 #     input clock frequency (before any prescaling is performed) in Hz. This value may
 #     differ from F_CPU if prescaling is used on the latter, and is required as the
 #     raw input clock is fed directly to the PLL sections of the AVR for high speed
@@ -98,7 +98,7 @@ F_CPU = 8000000
 #
 #     If no clock division is performed on the input clock inside the AVR (via the
 #     CPU clock adjust registers or the clock division fuses), this will be equal to F_CPU.
-F_CLOCK = $(F_CPU)
+F_USB = $(F_CPU)
 
 
 # Output format. (can be srec, ihex, binary)
@@ -180,20 +180,20 @@ CSTANDARD = -std=c99
 
 # Place -D or -U options here for C sources
 CDEFS  = -DF_CPU=$(F_CPU)UL
-CDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CDEFS += -DF_USB=$(F_USB)UL
 CDEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 CDEFS += $(LUFA_OPTS)
 
 
 # Place -D or -U options here for ASM sources
 ADEFS  = -DF_CPU=$(F_CPU)
-ADEFS += -DF_CLOCK=$(F_CLOCK)UL
+ADEFS += -DF_USB=$(F_USB)UL
 ADEFS += -DBOARD=BOARD_$(BOARD)
 ADEFS += $(LUFA_OPTS)
 
 # Place -D or -U options here for C++ sources
 CPPDEFS  = -DF_CPU=$(F_CPU)UL
-CPPDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CPPDEFS += -DF_USB=$(F_USB)UL
 CPPDEFS += -DBOARD=BOARD_$(BOARD)
 CPPDEFS += $(LUFA_OPTS)
 #CPPDEFS += -D__STDC_LIMIT_MACROS
diff --git a/Demos/Host/LowLevel/VirtualSerialHost/makefile b/Demos/Host/LowLevel/VirtualSerialHost/makefile
index c5e03c85089db7c8dcaf1741dc27caacd53fc754..473393247fc03ecc1749ad08dd9a603f65f51513 100644
--- a/Demos/Host/LowLevel/VirtualSerialHost/makefile
+++ b/Demos/Host/LowLevel/VirtualSerialHost/makefile
@@ -79,8 +79,8 @@ BOARD = USBKEY
 #     calculate timings. Do NOT tack on a 'UL' at the end, this will be done
 #     automatically to create a 32-bit value in your source code.
 #
-#     This will be an integer division of F_CLOCK below, as it is sourced by
-#     F_CLOCK after it has run through any CPU prescalers. Note that this value
+#     This will be an integer division of F_USB below, as it is sourced by
+#     F_USB after it has run through any CPU prescalers. Note that this value
 #     does not *change* the processor frequency - it should merely be updated to
 #     reflect the processor speed set externally so that the code can use accurate
 #     software delays.
@@ -88,7 +88,7 @@ F_CPU = 8000000
 
 
 # Input clock frequency.
-#     This will define a symbol, F_CLOCK, in all source code files equal to the
+#     This will define a symbol, F_USB, in all source code files equal to the
 #     input clock frequency (before any prescaling is performed) in Hz. This value may
 #     differ from F_CPU if prescaling is used on the latter, and is required as the
 #     raw input clock is fed directly to the PLL sections of the AVR for high speed
@@ -98,7 +98,7 @@ F_CPU = 8000000
 #
 #     If no clock division is performed on the input clock inside the AVR (via the
 #     CPU clock adjust registers or the clock division fuses), this will be equal to F_CPU.
-F_CLOCK = $(F_CPU)
+F_USB = $(F_CPU)
 
 
 # Output format. (can be srec, ihex, binary)
@@ -179,20 +179,20 @@ CSTANDARD = -std=c99
 
 # Place -D or -U options here for C sources
 CDEFS  = -DF_CPU=$(F_CPU)UL
-CDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CDEFS += -DF_USB=$(F_USB)UL
 CDEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 CDEFS += $(LUFA_OPTS)
 
 
 # Place -D or -U options here for ASM sources
 ADEFS  = -DF_CPU=$(F_CPU)
-ADEFS += -DF_CLOCK=$(F_CLOCK)UL
+ADEFS += -DF_USB=$(F_USB)UL
 ADEFS += -DBOARD=BOARD_$(BOARD)
 ADEFS += $(LUFA_OPTS)
 
 # Place -D or -U options here for C++ sources
 CPPDEFS  = -DF_CPU=$(F_CPU)UL
-CPPDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CPPDEFS += -DF_USB=$(F_USB)UL
 CPPDEFS += -DBOARD=BOARD_$(BOARD)
 CPPDEFS += $(LUFA_OPTS)
 #CPPDEFS += -D__STDC_LIMIT_MACROS
diff --git a/LUFA/Drivers/USB/Core/AVR8/USBController_AVR8.h b/LUFA/Drivers/USB/Core/AVR8/USBController_AVR8.h
index 77e92cb27f5aa39e56cb2eb89d5a21356e38beb4..a6e0067e3c126ac94c880ddfe9c32f06233c58d2 100644
--- a/LUFA/Drivers/USB/Core/AVR8/USBController_AVR8.h
+++ b/LUFA/Drivers/USB/Core/AVR8/USBController_AVR8.h
@@ -80,11 +80,11 @@
 			#error Do not include this file directly. Include LUFA/Drivers/USB/USB.h instead.
 		#endif
 
-		#if !defined(F_CLOCK)
-			#error F_CLOCK is not defined. You must define F_CLOCK to the frequency of the unprescaled USB controller clock in your project makefile.
+		#if !defined(F_USB)
+			#error F_USB is not defined. You must define F_USB to the frequency of the unprescaled USB controller clock in your project makefile.
 		#endif
 
-		#if (F_CLOCK == 8000000)
+		#if (F_USB == 8000000)
 			#if (defined(__AVR_AT90USB82__) || defined(__AVR_AT90USB162__) || \
 			     defined(__AVR_ATmega8U2__) || defined(__AVR_ATmega16U2__) || \
 			     defined(__AVR_ATmega32U2__))
@@ -96,7 +96,7 @@
 			#elif (defined(__AVR_AT90USB647__)  || defined(__AVR_AT90USB1287__))
 				#define USB_PLL_PSC                ((1 << PLLP1) | (1 << PLLP0))
 			#endif
-		#elif (F_CLOCK == 16000000)
+		#elif (F_USB == 16000000)
 			#if (defined(__AVR_AT90USB82__) || defined(__AVR_AT90USB162__) || \
 			     defined(__AVR_ATmega8U2__) || defined(__AVR_ATmega16U2__) || \
 			     defined(__AVR_ATmega32U2__))
@@ -111,7 +111,7 @@
 		#endif
 
 		#if !defined(USB_PLL_PSC)
-			#error No PLL prescale value available for chosen F_CLOCK value and AVR model.
+			#error No PLL prescale value available for chosen F_USB value and AVR model.
 		#endif
 
 	/* Public Interface - May be used in end-application: */
diff --git a/LUFA/Drivers/USB/Core/HostStandardReq.c b/LUFA/Drivers/USB/Core/HostStandardReq.c
index d2523fdefbbbe2af4a58dcfb67803d9a8161b274..5b443e7720dcad08f578b0846737919d0371051a 100644
--- a/LUFA/Drivers/USB/Core/HostStandardReq.c
+++ b/LUFA/Drivers/USB/Core/HostStandardReq.c
@@ -38,7 +38,6 @@
 
 uint8_t USB_Host_SendControlRequest(void* const BufferPtr)
 {
-	uint8_t* HeaderStream = (uint8_t*)&USB_ControlRequest;
 	uint8_t* DataStream   = (uint8_t*)BufferPtr;
 	bool     BusSuspended = USB_Host_IsBusSuspended();
 	uint8_t  ReturnStatus = HOST_SENDCONTROL_Successful;
diff --git a/LUFA/Drivers/USB/Core/UC3/USBController_UC3.c b/LUFA/Drivers/USB/Core/UC3/USBController_UC3.c
index a9ac2481c89fd81512e2e4bb114f73337d0a1ca5..e3d97d68491c5bde0b8c07ea4d21d3346c67f52f 100644
--- a/LUFA/Drivers/USB/Core/UC3/USBController_UC3.c
+++ b/LUFA/Drivers/USB/Core/UC3/USBController_UC3.c
@@ -106,8 +106,8 @@ void USB_ResetInterface(void)
 
 	AVR32_PM.GCCTRL[AVR32_PM_GCLK_USBB].pllsel = !(USB_Options & USB_OPT_GCLK_SRC_OSC);
 	AVR32_PM.GCCTRL[AVR32_PM_GCLK_USBB].oscsel = !(USB_Options & USB_OPT_GCLK_CHANNEL_0);
-	AVR32_PM.GCCTRL[AVR32_PM_GCLK_USBB].diven  = (F_CLOCK != USB_CLOCK_REQUIRED_FREQ);
-	AVR32_PM.GCCTRL[AVR32_PM_GCLK_USBB].div    = (F_CLOCK == USB_CLOCK_REQUIRED_FREQ) ? 0 : (uint32_t)(((F_CLOCK / USB_CLOCK_REQUIRED_FREQ) - 1) / 2);
+	AVR32_PM.GCCTRL[AVR32_PM_GCLK_USBB].diven  = (F_USB != USB_CLOCK_REQUIRED_FREQ);
+	AVR32_PM.GCCTRL[AVR32_PM_GCLK_USBB].div    = (F_USB == USB_CLOCK_REQUIRED_FREQ) ? 0 : (uint32_t)(((F_USB / USB_CLOCK_REQUIRED_FREQ) - 1) / 2);
 	AVR32_PM.GCCTRL[AVR32_PM_GCLK_USBB].cen    = true;
 
 	USB_INT_DisableAllInterrupts();
diff --git a/LUFA/ManPages/ChangeLog.txt b/LUFA/ManPages/ChangeLog.txt
index 3bb93ea8dbc2002d241dae0d9dbe5ffb6ca3d390..7b5c667e66fa1226f3fde9caa29eaf03a7561a97 100644
--- a/LUFA/ManPages/ChangeLog.txt
+++ b/LUFA/ManPages/ChangeLog.txt
@@ -60,6 +60,7 @@
   *   - Removed Pipe_ClearErrorFlags(), pipe error flags are now automatically cleared when Pipe_ClearError() is called
   *   - Endpoint_ResetFIFO() renamed to Endpoint_ResetEndpoint(), to be consistent with the Pipe_ResetPipe() function name
   *   - Implemented on-demand PLL clock generation for the U4, U6 and U7 series USB AVRs when automatic PLL mode is specified
+  *   - F_CLOCK changed to F_USB to be more descriptive, and applicable on future architecture ports
   *  - Library Applications:
   *   - Changed the XPLAINBridge software UART to use the regular timer CTC mode instead of the alternative CTC mode
   *     via the Input Capture register, to reduce user confusion
@@ -633,7 +634,7 @@
   *  - Pipe stream functions now automatically set the correct pipe token, so that bidirectional pipes can be used
   *  - Pipe_ConfigurePipe() now automatically defaults IN pipes to accepting infinite IN requests, this can still be changed by calling
   *    the existing Pipe_SetFiniteINRequests() function
-  *  - Changed F_CLOCK entries in project makefiles to alias to F_CPU by default, as this is the most common case
+  *  - Changed F_USB entries in project makefiles to alias to F_CPU by default, as this is the most common case
   *  - Host mode demos now use sane terminal escape codes, so that text is always readable and events/program output is visually distinguished
   *    from one another using foreground colours
   *  - Internal per-device preprocessing conditions changed to per-device series rather than per-controller group for finer-grain
@@ -789,7 +790,7 @@
   *  - Fixed KeyboardMouse demo discarding the wIndex value in the REQ_GetReport request
   *  - USBtoSerial demo now discards all Rx data when not connected to a USB host, rather than buffering characters for transmission
   *    next time the device is attached to a host.
-  *  - Added new F_CLOCK compile time constant to the library and makefiles, to give the raw input clock (used to feed the PLL before any
+  *  - Added new F_USB compile time constant to the library and makefiles, to give the raw input clock (used to feed the PLL before any
   *    clock prescaling is performed) frequency, so that the PLL prescale mask can be determined
   *  - Changed stream wait timeout counter to be 16-bit, so that very long timeout periods can be set for correct communications with
   *    badly designed hosts or devices which greatly exceed the USB specification limits
diff --git a/LUFA/ManPages/ConfiguringApps.txt b/LUFA/ManPages/ConfiguringApps.txt
index e5ce9fd5153903dedef02f662167fb15297203db..b56341ee29a6660e359d10efed0472755c7ff28b 100644
--- a/LUFA/ManPages/ConfiguringApps.txt
+++ b/LUFA/ManPages/ConfiguringApps.txt
@@ -22,7 +22,7 @@
  *
  *    - <b>MCU</b>, the target AVR processor
  *    - <b>BOARD</b>, the target board hardware
- *    - <b>F_CLOCK</b>, the target raw master clock frequency, before any prescaling is performed
+ *    - <b>F_USB</b>, the target raw master clock frequency, before any prescaling is performed
  *    - <b>F_CPU</b>, the target AVR CPU master clock frequency, after any prescaling
  *    - <b>CDEFS</b>, the C preprocessor defines which configure options the source code
  *    - <b>LUFA_PATH</b>, the path to the LUFA library source code
@@ -50,7 +50,7 @@
  *
  *  For boards with built in hardware driver support within the LUFA library, see \ref Page_DeviceSupport.
  *
- *  \section Sec_F_CLOCK The F_CLOCK Parameter
+ *  \section Sec_F_USB The F_USB Parameter
  *  This parameter indicates the target AVR's input clock frequency, in Hz. This is the actual clock input, before any prescaling is performed. In the
  *  USB AVR architecture, the input clock before any prescaling is fed directly to the PLL subsystem, and thus the PLL is derived directly from the
  *  clock input. The PLL then feeds the USB and other sections of the AVR with the correct upscaled frequencies required for those sections to function.
diff --git a/LUFA/ManPages/LUFAPoweredProjects.txt b/LUFA/ManPages/LUFAPoweredProjects.txt
index 34d4944b654efdd618233a060fdec91848e56964..b81d03e656ce6449d6c33ba562cf8c849df0c8ef 100644
--- a/LUFA/ManPages/LUFAPoweredProjects.txt
+++ b/LUFA/ManPages/LUFAPoweredProjects.txt
@@ -51,6 +51,7 @@
  *  - Garmin GPS USB to NMEA standard serial sentence translator: http://github.com/nall/garmin-transmogrifier/tree/master
  *  - Generic HID Device Creator: http://generichid.sourceforge.net/
  *  - Ghetto Drum, a MIDI drum controller: http://noisybox.net/art/gdrum/
+ *  - Hiduino, a USB-MIDI replacement firmware for the Arduino Uno: http://code.google.com/p/hiduino/
  *  - IR Remote to Keyboard decoder: http://netzhansa.blogspot.com/2010/04/our-living-room-hi-fi-setup-needs-mp3.html
  *  - LED Panel controller: http://projects.peterpolidoro.net/caltech/panelscontroller/panelscontroller.htm
  *  - LUFA powered DDR dance mat (French): http://logicien-parfait.fr/dokuwiki/doku.php?id=projet:ddr_repair
@@ -78,10 +79,12 @@
  *  - Stripe Snoop, a Magnetic Card reader: http://www.ossguy.com/ss_usb/
  *  - Teensy SD Card .WAV file player: http://elasticsheep.com/2010/04/teensy2-usb-wav-player-part-1/
  *  - Touchscreen Input Device: http://capnstech.blogspot.com/2010/07/touchscreen-update.html
+ *  - Universal USB AVR Module: http://usbavr.bplaced.net/
  *  - USB Interface for Playstation Portable Devices: http://forums.ps2dev.org/viewtopic.php?t=11001
  *  - Userial, a USB to Serial converter with SPI, I2C and other protocols: http://www.tty1.net/userial/
  *  - Wireless MIDI Guitar system: http://www.ise.pw.edu.pl/~wzab/wireless_guitar_system/
  *  - XUM1541, a Commodore 64 floppy drive to USB adapter: http://www.root.org/~nate/c64/xum1541/
+ *  - Zeus, a touch screen computer for music manipulation: http://www.benbengler.com/developments_zeus.html
  *
  *  \section Sec_LUFACommercialProjects Projects Using LUFA (Commercial)
  *
diff --git a/LUFA/ManPages/MigrationInformation.txt b/LUFA/ManPages/MigrationInformation.txt
index c562ccdd3f6d9052fd13a63f8b8bcdc3106f7b4c..cb94bad9a961f2d82bd0ea85fc9032d7ac5a0c22 100644
--- a/LUFA/ManPages/MigrationInformation.txt
+++ b/LUFA/ManPages/MigrationInformation.txt
@@ -32,6 +32,8 @@
  *      reconfiguring all Endpoints/Pipes in order each time a new Endpoint/Pipe is created. To minimise the compiled program
  *      size, the new \c ORDERED_EP_CONFIG compile time option may be defined in the project makefile to restrict the ordering
  *      in exchange for a smaller compiled binary size.
+ *    - The previous F_CLOCK symbol, required in the project makefile, has been renamed to F_USB. This is due to the previous name
+ *      being far too generic for use in future architecture ports, where multiple clock domains are used.
  *
  *  <b>Device Mode</b>
  *    - The Endpoint stream functions now all require a \c BytesProcessed parameter instead of the previous callback parameter.
@@ -368,7 +370,7 @@
  *  \section Sec_Migration090401 Migrating from 090209 to 090401
  *
  *  <b>All</b>
- *    - LUFA projects must now give the raw input clock frequency (before any prescaling) as a compile time constant \c F_CLOCK,
+ *    - LUFA projects must now give the raw input clock frequency (before any prescaling) as a compile time constant \c F_USB,
  *      defined in the project makefile and passed to the compiler via the -D switch.
  *    - The makefile EEPROM programming targets for FLIP and dfu-programmer no longer program in the FLASH data in addition to the
  *      EEPROM data into the device. If both are to be programmed, both the EEPROM and FLASH programming targets must be called.
diff --git a/Projects/AVRISP-MKII/makefile b/Projects/AVRISP-MKII/makefile
index ecfa0a1288782f926778b64c36af634337f56a09..de1e225dac32f7e5363db10f9c5db84241c958d0 100644
--- a/Projects/AVRISP-MKII/makefile
+++ b/Projects/AVRISP-MKII/makefile
@@ -79,8 +79,8 @@ BOARD = USBTINYMKII
 #     calculate timings. Do NOT tack on a 'UL' at the end, this will be done
 #     automatically to create a 32-bit value in your source code.
 #
-#     This will be an integer division of F_CLOCK below, as it is sourced by
-#     F_CLOCK after it has run through any CPU prescalers. Note that this value
+#     This will be an integer division of F_USB below, as it is sourced by
+#     F_USB after it has run through any CPU prescalers. Note that this value
 #     does not *change* the processor frequency - it should merely be updated to
 #     reflect the processor speed set externally so that the code can use accurate
 #     software delays.
@@ -88,7 +88,7 @@ F_CPU = 16000000
 
 
 # Input clock frequency.
-#     This will define a symbol, F_CLOCK, in all source code files equal to the
+#     This will define a symbol, F_USB, in all source code files equal to the
 #     input clock frequency (before any prescaling is performed) in Hz. This value may
 #     differ from F_CPU if prescaling is used on the latter, and is required as the
 #     raw input clock is fed directly to the PLL sections of the AVR for high speed
@@ -98,7 +98,7 @@ F_CPU = 16000000
 #
 #     If no clock division is performed on the input clock inside the AVR (via the
 #     CPU clock adjust registers or the clock division fuses), this will be equal to F_CPU.
-F_CLOCK = $(F_CPU)
+F_USB = $(F_CPU)
 
 
 # Output format. (can be srec, ihex, binary)
@@ -207,20 +207,20 @@ CSTANDARD = -std=c99
 
 # Place -D or -U options here for C sources
 CDEFS  = -DF_CPU=$(F_CPU)UL
-CDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CDEFS += -DF_USB=$(F_USB)UL
 CDEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 CDEFS += $(LUFA_OPTS)
 
 
 # Place -D or -U options here for ASM sources
 ADEFS  = -DF_CPU=$(F_CPU)
-ADEFS += -DF_CLOCK=$(F_CLOCK)UL
+ADEFS += -DF_USB=$(F_USB)UL
 ADEFS += -DBOARD=BOARD_$(BOARD)
 ADEFS += $(LUFA_OPTS)
 
 # Place -D or -U options here for C++ sources
 CPPDEFS  = -DF_CPU=$(F_CPU)UL
-CPPDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CPPDEFS += -DF_USB=$(F_USB)UL
 CPPDEFS += -DBOARD=BOARD_$(BOARD)
 CPPDEFS += $(LUFA_OPTS)
 #CPPDEFS += -D__STDC_LIMIT_MACROS
diff --git a/Projects/Benito/makefile b/Projects/Benito/makefile
index 9b19f0da2e369ee3ba73bc24abb7b99e5ccfaebf..152537b79b5fc37a19341796cd600abbe96232eb 100644
--- a/Projects/Benito/makefile
+++ b/Projects/Benito/makefile
@@ -79,8 +79,8 @@ BOARD = BENITO
 #     calculate timings. Do NOT tack on a 'UL' at the end, this will be done
 #     automatically to create a 32-bit value in your source code.
 #
-#     This will be an integer division of F_CLOCK below, as it is sourced by
-#     F_CLOCK after it has run through any CPU prescalers. Note that this value
+#     This will be an integer division of F_USB below, as it is sourced by
+#     F_USB after it has run through any CPU prescalers. Note that this value
 #     does not *change* the processor frequency - it should merely be updated to
 #     reflect the processor speed set externally so that the code can use accurate
 #     software delays.
@@ -88,7 +88,7 @@ F_CPU = 8000000
 
 
 # Input clock frequency.
-#     This will define a symbol, F_CLOCK, in all source code files equal to the
+#     This will define a symbol, F_USB, in all source code files equal to the
 #     input clock frequency (before any prescaling is performed) in Hz. This value may
 #     differ from F_CPU if prescaling is used on the latter, and is required as the
 #     raw input clock is fed directly to the PLL sections of the AVR for high speed
@@ -98,7 +98,7 @@ F_CPU = 8000000
 #
 #     If no clock division is performed on the input clock inside the AVR (via the
 #     CPU clock adjust registers or the clock division fuses), this will be equal to F_CPU.
-F_CLOCK = $(F_CPU)
+F_USB = $(F_CPU)
 
 
 # Output format. (can be srec, ihex, binary)
@@ -193,20 +193,20 @@ CSTANDARD = -std=c99
 
 # Place -D or -U options here for C sources
 CDEFS  = -DF_CPU=$(F_CPU)UL
-CDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CDEFS += -DF_USB=$(F_USB)UL
 CDEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 CDEFS += $(LUFA_OPTS)
 
 
 # Place -D or -U options here for ASM sources
 ADEFS  = -DF_CPU=$(F_CPU)
-ADEFS += -DF_CLOCK=$(F_CLOCK)UL
+ADEFS += -DF_USB=$(F_USB)UL
 ADEFS += -DBOARD=BOARD_$(BOARD)
 ADEFS += $(LUFA_OPTS)
 
 # Place -D or -U options here for C++ sources
 CPPDEFS  = -DF_CPU=$(F_CPU)UL
-CPPDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CPPDEFS += -DF_USB=$(F_USB)UL
 CPPDEFS += -DBOARD=BOARD_$(BOARD)
 CPPDEFS += $(LUFA_OPTS)
 #CPPDEFS += -D__STDC_LIMIT_MACROS
diff --git a/Projects/Incomplete/StandaloneProgrammer/makefile b/Projects/Incomplete/StandaloneProgrammer/makefile
index 8d6fcedca3729de45807aaa70e890939bc0a961b..de65ad81fc7e45fbae9ed150bb7a7398b8c42c05 100644
--- a/Projects/Incomplete/StandaloneProgrammer/makefile
+++ b/Projects/Incomplete/StandaloneProgrammer/makefile
@@ -79,8 +79,8 @@ BOARD = USBKEY
 #     calculate timings. Do NOT tack on a 'UL' at the end, this will be done
 #     automatically to create a 32-bit value in your source code.
 #
-#     This will be an integer division of F_CLOCK below, as it is sourced by
-#     F_CLOCK after it has run through any CPU prescalers. Note that this value
+#     This will be an integer division of F_USB below, as it is sourced by
+#     F_USB after it has run through any CPU prescalers. Note that this value
 #     does not *change* the processor frequency - it should merely be updated to
 #     reflect the processor speed set externally so that the code can use accurate
 #     software delays.
@@ -88,7 +88,7 @@ F_CPU = 8000000
 
 
 # Input clock frequency.
-#     This will define a symbol, F_CLOCK, in all source code files equal to the
+#     This will define a symbol, F_USB, in all source code files equal to the
 #     input clock frequency (before any prescaling is performed) in Hz. This value may
 #     differ from F_CPU if prescaling is used on the latter, and is required as the
 #     raw input clock is fed directly to the PLL sections of the AVR for high speed
@@ -98,7 +98,7 @@ F_CPU = 8000000
 #
 #     If no clock division is performed on the input clock inside the AVR (via the
 #     CPU clock adjust registers or the clock division fuses), this will be equal to F_CPU.
-F_CLOCK = $(F_CPU)
+F_USB = $(F_CPU)
 
 
 # Output format. (can be srec, ihex, binary)
@@ -193,20 +193,20 @@ CSTANDARD = -std=c99
 
 # Place -D or -U options here for C sources
 CDEFS  = -DF_CPU=$(F_CPU)UL
-CDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CDEFS += -DF_USB=$(F_USB)UL
 CDEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 CDEFS += $(LUFA_OPTS)
 
 
 # Place -D or -U options here for ASM sources
 ADEFS  = -DF_CPU=$(F_CPU)
-ADEFS += -DF_CLOCK=$(F_CLOCK)UL
+ADEFS += -DF_USB=$(F_USB)UL
 ADEFS += -DBOARD=BOARD_$(BOARD)
 ADEFS += $(LUFA_OPTS)
 
 # Place -D or -U options here for C++ sources
 CPPDEFS  = -DF_CPU=$(F_CPU)UL
-CPPDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CPPDEFS += -DF_USB=$(F_USB)UL
 CPPDEFS += -DBOARD=BOARD_$(BOARD)
 CPPDEFS += $(LUFA_OPTS)
 #CPPDEFS += -D__STDC_LIMIT_MACROS
diff --git a/Projects/LEDNotifier/makefile b/Projects/LEDNotifier/makefile
index a29ff5404e5e8fd55f0b4adff0e6382bcb1e8ef4..da89b7e308bcf0a456ebe67df9744c4c01f12afc 100644
--- a/Projects/LEDNotifier/makefile
+++ b/Projects/LEDNotifier/makefile
@@ -79,8 +79,8 @@ BOARD = BUI
 #     calculate timings. Do NOT tack on a 'UL' at the end, this will be done
 #     automatically to create a 32-bit value in your source code.
 #
-#     This will be an integer division of F_CLOCK below, as it is sourced by
-#     F_CLOCK after it has run through any CPU prescalers. Note that this value
+#     This will be an integer division of F_USB below, as it is sourced by
+#     F_USB after it has run through any CPU prescalers. Note that this value
 #     does not *change* the processor frequency - it should merely be updated to
 #     reflect the processor speed set externally so that the code can use accurate
 #     software delays.
@@ -88,7 +88,7 @@ F_CPU = 8000000
 
 
 # Input clock frequency.
-#     This will define a symbol, F_CLOCK, in all source code files equal to the
+#     This will define a symbol, F_USB, in all source code files equal to the
 #     input clock frequency (before any prescaling is performed) in Hz. This value may
 #     differ from F_CPU if prescaling is used on the latter, and is required as the
 #     raw input clock is fed directly to the PLL sections of the AVR for high speed
@@ -98,7 +98,7 @@ F_CPU = 8000000
 #
 #     If no clock division is performed on the input clock inside the AVR (via the
 #     CPU clock adjust registers or the clock division fuses), this will be equal to F_CPU.
-F_CLOCK = $(F_CPU)
+F_USB = $(F_CPU)
 
 
 # Output format. (can be srec, ihex, binary)
@@ -184,20 +184,20 @@ CSTANDARD = -std=c99
 
 # Place -D or -U options here for C sources
 CDEFS  = -DF_CPU=$(F_CPU)UL
-CDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CDEFS += -DF_USB=$(F_USB)UL
 CDEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 CDEFS += $(LUFA_OPTS)
 
 
 # Place -D or -U options here for ASM sources
 ADEFS  = -DF_CPU=$(F_CPU)
-ADEFS += -DF_CLOCK=$(F_CLOCK)UL
+ADEFS += -DF_USB=$(F_USB)UL
 ADEFS += -DBOARD=BOARD_$(BOARD)
 ADEFS += $(LUFA_OPTS)
 
 # Place -D or -U options here for C++ sources
 CPPDEFS  = -DF_CPU=$(F_CPU)UL
-CPPDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CPPDEFS += -DF_USB=$(F_USB)UL
 CPPDEFS += -DBOARD=BOARD_$(BOARD)
 CPPDEFS += $(LUFA_OPTS)
 #CPPDEFS += -D__STDC_LIMIT_MACROS
diff --git a/Projects/MIDIToneGenerator/makefile b/Projects/MIDIToneGenerator/makefile
index 4ae7862213533c9a2f055a9030a6d29b06a933ed..fbabbf70dce7ae81c773f4b35ead0b9061cbc5a2 100644
--- a/Projects/MIDIToneGenerator/makefile
+++ b/Projects/MIDIToneGenerator/makefile
@@ -79,8 +79,8 @@ BOARD = USBKEY
 #     calculate timings. Do NOT tack on a 'UL' at the end, this will be done
 #     automatically to create a 32-bit value in your source code.
 #
-#     This will be an integer division of F_CLOCK below, as it is sourced by
-#     F_CLOCK after it has run through any CPU prescalers. Note that this value
+#     This will be an integer division of F_USB below, as it is sourced by
+#     F_USB after it has run through any CPU prescalers. Note that this value
 #     does not *change* the processor frequency - it should merely be updated to
 #     reflect the processor speed set externally so that the code can use accurate
 #     software delays.
@@ -88,7 +88,7 @@ F_CPU = 8000000
 
 
 # Input clock frequency.
-#     This will define a symbol, F_CLOCK, in all source code files equal to the
+#     This will define a symbol, F_USB, in all source code files equal to the
 #     input clock frequency (before any prescaling is performed) in Hz. This value may
 #     differ from F_CPU if prescaling is used on the latter, and is required as the
 #     raw input clock is fed directly to the PLL sections of the AVR for high speed
@@ -98,7 +98,7 @@ F_CPU = 8000000
 #
 #     If no clock division is performed on the input clock inside the AVR (via the
 #     CPU clock adjust registers or the clock division fuses), this will be equal to F_CPU.
-F_CLOCK = $(F_CPU)
+F_USB = $(F_CPU)
 
 
 # Output format. (can be srec, ihex, binary)
@@ -184,20 +184,20 @@ CSTANDARD = -std=c99
 
 # Place -D or -U options here for C sources
 CDEFS  = -DF_CPU=$(F_CPU)UL
-CDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CDEFS += -DF_USB=$(F_USB)UL
 CDEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 CDEFS += $(LUFA_OPTS)
 
 
 # Place -D or -U options here for ASM sources
 ADEFS  = -DF_CPU=$(F_CPU)
-ADEFS += -DF_CLOCK=$(F_CLOCK)UL
+ADEFS += -DF_USB=$(F_USB)UL
 ADEFS += -DBOARD=BOARD_$(BOARD)
 ADEFS += $(LUFA_OPTS)
 
 # Place -D or -U options here for C++ sources
 CPPDEFS  = -DF_CPU=$(F_CPU)UL
-CPPDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CPPDEFS += -DF_USB=$(F_USB)UL
 CPPDEFS += -DBOARD=BOARD_$(BOARD)
 CPPDEFS += $(LUFA_OPTS)
 #CPPDEFS += -D__STDC_LIMIT_MACROS
diff --git a/Projects/Magstripe/makefile b/Projects/Magstripe/makefile
index 9e6674f3623c9032ba08da7490b9895c1a6ccbe3..b399dcdcf06b2c0f8ac6c7edf2a9f41840bb9df3 100644
--- a/Projects/Magstripe/makefile
+++ b/Projects/Magstripe/makefile
@@ -79,8 +79,8 @@ BOARD = NONE
 #     calculate timings. Do NOT tack on a 'UL' at the end, this will be done
 #     automatically to create a 32-bit value in your source code.
 #
-#     This will be an integer division of F_CLOCK below, as it is sourced by
-#     F_CLOCK after it has run through any CPU prescalers. Note that this value
+#     This will be an integer division of F_USB below, as it is sourced by
+#     F_USB after it has run through any CPU prescalers. Note that this value
 #     does not *change* the processor frequency - it should merely be updated to
 #     reflect the processor speed set externally so that the code can use accurate
 #     software delays.
@@ -88,7 +88,7 @@ F_CPU = 16000000
 
 
 # Input clock frequency.
-#     This will define a symbol, F_CLOCK, in all source code files equal to the
+#     This will define a symbol, F_USB, in all source code files equal to the
 #     input clock frequency (before any prescaling is performed) in Hz. This value may
 #     differ from F_CPU if prescaling is used on the latter, and is required as the
 #     raw input clock is fed directly to the PLL sections of the AVR for high speed
@@ -98,7 +98,7 @@ F_CPU = 16000000
 #
 #     If no clock division is performed on the input clock inside the AVR (via the
 #     CPU clock adjust registers or the clock division fuses), this will be equal to F_CPU.
-F_CLOCK = $(F_CPU)
+F_USB = $(F_CPU)
 
 
 # Output format. (can be srec, ihex, binary)
@@ -196,20 +196,20 @@ CSTANDARD = -std=c99
 
 # Place -D or -U options here for C sources
 CDEFS  = -DF_CPU=$(F_CPU)UL
-CDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CDEFS += -DF_USB=$(F_USB)UL
 CDEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 CDEFS += $(LUFA_OPTS)
 
 
 # Place -D or -U options here for ASM sources
 ADEFS  = -DF_CPU=$(F_CPU)
-ADEFS += -DF_CLOCK=$(F_CLOCK)UL
+ADEFS += -DF_USB=$(F_USB)UL
 ADEFS += -DBOARD=BOARD_$(BOARD)
 ADEFS += $(LUFA_OPTS)
 
 # Place -D or -U options here for C++ sources
 CPPDEFS  = -DF_CPU=$(F_CPU)UL
-CPPDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CPPDEFS += -DF_USB=$(F_USB)UL
 CPPDEFS += -DBOARD=BOARD_$(BOARD)
 CPPDEFS += $(LUFA_OPTS)
 #CPPDEFS += -D__STDC_LIMIT_MACROS
diff --git a/Projects/MissileLauncher/makefile b/Projects/MissileLauncher/makefile
index e3e550e64a73d86a30a6e210885e07b9c35be6d7..4931e54c76191dc0016469bb1d3acbcd02975722 100644
--- a/Projects/MissileLauncher/makefile
+++ b/Projects/MissileLauncher/makefile
@@ -79,8 +79,8 @@ BOARD = USBKEY
 #     calculate timings. Do NOT tack on a 'UL' at the end, this will be done
 #     automatically to create a 32-bit value in your source code.
 #
-#     This will be an integer division of F_CLOCK below, as it is sourced by
-#     F_CLOCK after it has run through any CPU prescalers. Note that this value
+#     This will be an integer division of F_USB below, as it is sourced by
+#     F_USB after it has run through any CPU prescalers. Note that this value
 #     does not *change* the processor frequency - it should merely be updated to
 #     reflect the processor speed set externally so that the code can use accurate
 #     software delays.
@@ -88,7 +88,7 @@ F_CPU = 8000000
 
 
 # Input clock frequency.
-#     This will define a symbol, F_CLOCK, in all source code files equal to the
+#     This will define a symbol, F_USB, in all source code files equal to the
 #     input clock frequency (before any prescaling is performed) in Hz. This value may
 #     differ from F_CPU if prescaling is used on the latter, and is required as the
 #     raw input clock is fed directly to the PLL sections of the AVR for high speed
@@ -98,7 +98,7 @@ F_CPU = 8000000
 #
 #     If no clock division is performed on the input clock inside the AVR (via the
 #     CPU clock adjust registers or the clock division fuses), this will be equal to F_CPU.
-F_CLOCK = $(F_CPU)
+F_USB = $(F_CPU)
 
 
 # Output format. (can be srec, ihex, binary)
@@ -180,20 +180,20 @@ CSTANDARD = -std=c99
 
 # Place -D or -U options here for C sources
 CDEFS  = -DF_CPU=$(F_CPU)UL
-CDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CDEFS += -DF_USB=$(F_USB)UL
 CDEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 CDEFS += $(LUFA_OPTS)
 
 
 # Place -D or -U options here for ASM sources
 ADEFS  = -DF_CPU=$(F_CPU)
-ADEFS += -DF_CLOCK=$(F_CLOCK)UL
+ADEFS += -DF_USB=$(F_USB)UL
 ADEFS += -DBOARD=BOARD_$(BOARD)
 ADEFS += $(LUFA_OPTS)
 
 # Place -D or -U options here for C++ sources
 CPPDEFS  = -DF_CPU=$(F_CPU)UL
-CPPDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CPPDEFS += -DF_USB=$(F_USB)UL
 CPPDEFS += -DBOARD=BOARD_$(BOARD)
 CPPDEFS += $(LUFA_OPTS)
 #CPPDEFS += -D__STDC_LIMIT_MACROS
diff --git a/Projects/RelayBoard/makefile b/Projects/RelayBoard/makefile
index d548ff48354c8e98335b67ea3ffeb653ec55130e..9cfc24765346d7c6183324b5a392b3863eb4e805 100644
--- a/Projects/RelayBoard/makefile
+++ b/Projects/RelayBoard/makefile
@@ -79,8 +79,8 @@ BOARD = USBKEY
 #     calculate timings. Do NOT tack on a 'UL' at the end, this will be done
 #     automatically to create a 32-bit value in your source code.
 #
-#     This will be an integer division of F_CLOCK below, as it is sourced by
-#     F_CLOCK after it has run through any CPU prescalers. Note that this value
+#     This will be an integer division of F_USB below, as it is sourced by
+#     F_USB after it has run through any CPU prescalers. Note that this value
 #     does not *change* the processor frequency - it should merely be updated to
 #     reflect the processor speed set externally so that the code can use accurate
 #     software delays.
@@ -88,7 +88,7 @@ F_CPU = 8000000
 
 
 # Input clock frequency.
-#     This will define a symbol, F_CLOCK, in all source code files equal to the
+#     This will define a symbol, F_USB, in all source code files equal to the
 #     input clock frequency (before any prescaling is performed) in Hz. This value may
 #     differ from F_CPU if prescaling is used on the latter, and is required as the
 #     raw input clock is fed directly to the PLL sections of the AVR for high speed
@@ -98,7 +98,7 @@ F_CPU = 8000000
 #
 #     If no clock division is performed on the input clock inside the AVR (via the
 #     CPU clock adjust registers or the clock division fuses), this will be equal to F_CPU.
-F_CLOCK = $(F_CPU)
+F_USB = $(F_CPU)
 
 
 # Output format. (can be srec, ihex, binary)
@@ -184,20 +184,20 @@ CSTANDARD = -std=c99
 
 # Place -D or -U options here for C sources
 CDEFS  = -DF_CPU=$(F_CPU)UL
-CDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CDEFS += -DF_USB=$(F_USB)UL
 CDEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 CDEFS += $(LUFA_OPTS)
 
 
 # Place -D or -U options here for ASM sources
 ADEFS  = -DF_CPU=$(F_CPU)
-ADEFS += -DF_CLOCK=$(F_CLOCK)UL
+ADEFS += -DF_USB=$(F_USB)UL
 ADEFS += -DBOARD=BOARD_$(BOARD)
 ADEFS += $(LUFA_OPTS)
 
 # Place -D or -U options here for C++ sources
 CPPDEFS  = -DF_CPU=$(F_CPU)UL
-CPPDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CPPDEFS += -DF_USB=$(F_USB)UL
 CPPDEFS += -DBOARD=BOARD_$(BOARD)
 CPPDEFS += $(LUFA_OPTS)
 #CPPDEFS += -D__STDC_LIMIT_MACROS
diff --git a/Projects/TempDataLogger/makefile b/Projects/TempDataLogger/makefile
index 66648165e3ad33ade9aaad7f46653382877841cd..3da1c5c3cbaed039b0b6d6b22418165d9e9dfd7f 100644
--- a/Projects/TempDataLogger/makefile
+++ b/Projects/TempDataLogger/makefile
@@ -79,8 +79,8 @@ BOARD = USBKEY
 #     calculate timings. Do NOT tack on a 'UL' at the end, this will be done
 #     automatically to create a 32-bit value in your source code.
 #
-#     This will be an integer division of F_CLOCK below, as it is sourced by
-#     F_CLOCK after it has run through any CPU prescalers. Note that this value
+#     This will be an integer division of F_USB below, as it is sourced by
+#     F_USB after it has run through any CPU prescalers. Note that this value
 #     does not *change* the processor frequency - it should merely be updated to
 #     reflect the processor speed set externally so that the code can use accurate
 #     software delays.
@@ -88,7 +88,7 @@ F_CPU = 8000000
 
 
 # Input clock frequency.
-#     This will define a symbol, F_CLOCK, in all source code files equal to the
+#     This will define a symbol, F_USB, in all source code files equal to the
 #     input clock frequency (before any prescaling is performed) in Hz. This value may
 #     differ from F_CPU if prescaling is used on the latter, and is required as the
 #     raw input clock is fed directly to the PLL sections of the AVR for high speed
@@ -98,7 +98,7 @@ F_CPU = 8000000
 #
 #     If no clock division is performed on the input clock inside the AVR (via the
 #     CPU clock adjust registers or the clock division fuses), this will be equal to F_CPU.
-F_CLOCK = $(F_CPU)
+F_USB = $(F_CPU)
 
 
 # Output format. (can be srec, ihex, binary)
@@ -193,20 +193,20 @@ CSTANDARD = -std=c99
 
 # Place -D or -U options here for C sources
 CDEFS  = -DF_CPU=$(F_CPU)UL
-CDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CDEFS += -DF_USB=$(F_USB)UL
 CDEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 CDEFS += $(LUFA_OPTS)
 
 
 # Place -D or -U options here for ASM sources
 ADEFS  = -DF_CPU=$(F_CPU)
-ADEFS += -DF_CLOCK=$(F_CLOCK)UL
+ADEFS += -DF_USB=$(F_USB)UL
 ADEFS += -DBOARD=BOARD_$(BOARD)
 ADEFS += $(LUFA_OPTS)
 
 # Place -D or -U options here for C++ sources
 CPPDEFS  = -DF_CPU=$(F_CPU)UL
-CPPDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CPPDEFS += -DF_USB=$(F_USB)UL
 CPPDEFS += -DBOARD=BOARD_$(BOARD)
 CPPDEFS += $(LUFA_OPTS)
 #CPPDEFS += -D__STDC_LIMIT_MACROS
diff --git a/Projects/USBtoSerial/makefile b/Projects/USBtoSerial/makefile
index 01141fd1d6dbbe9312d25f775e08700bc42d504e..42ed95461087283e64dd0fabce3a547e88126a79 100644
--- a/Projects/USBtoSerial/makefile
+++ b/Projects/USBtoSerial/makefile
@@ -79,8 +79,8 @@ BOARD = USBKEY
 #     calculate timings. Do NOT tack on a 'UL' at the end, this will be done
 #     automatically to create a 32-bit value in your source code.
 #
-#     This will be an integer division of F_CLOCK below, as it is sourced by
-#     F_CLOCK after it has run through any CPU prescalers. Note that this value
+#     This will be an integer division of F_USB below, as it is sourced by
+#     F_USB after it has run through any CPU prescalers. Note that this value
 #     does not *change* the processor frequency - it should merely be updated to
 #     reflect the processor speed set externally so that the code can use accurate
 #     software delays.
@@ -88,7 +88,7 @@ F_CPU = 8000000
 
 
 # Input clock frequency.
-#     This will define a symbol, F_CLOCK, in all source code files equal to the
+#     This will define a symbol, F_USB, in all source code files equal to the
 #     input clock frequency (before any prescaling is performed) in Hz. This value may
 #     differ from F_CPU if prescaling is used on the latter, and is required as the
 #     raw input clock is fed directly to the PLL sections of the AVR for high speed
@@ -98,7 +98,7 @@ F_CPU = 8000000
 #
 #     If no clock division is performed on the input clock inside the AVR (via the
 #     CPU clock adjust registers or the clock division fuses), this will be equal to F_CPU.
-F_CLOCK = $(F_CPU)
+F_USB = $(F_CPU)
 
 
 # Output format. (can be srec, ihex, binary)
@@ -185,20 +185,20 @@ CSTANDARD = -std=c99
 
 # Place -D or -U options here for C sources
 CDEFS  = -DF_CPU=$(F_CPU)UL
-CDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CDEFS += -DF_USB=$(F_USB)UL
 CDEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 CDEFS += $(LUFA_OPTS)
 
 
 # Place -D or -U options here for ASM sources
 ADEFS  = -DF_CPU=$(F_CPU)
-ADEFS += -DF_CLOCK=$(F_CLOCK)UL
+ADEFS += -DF_USB=$(F_USB)UL
 ADEFS += -DBOARD=BOARD_$(BOARD)
 ADEFS += $(LUFA_OPTS)
 
 # Place -D or -U options here for C++ sources
 CPPDEFS  = -DF_CPU=$(F_CPU)UL
-CPPDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CPPDEFS += -DF_USB=$(F_USB)UL
 CPPDEFS += -DBOARD=BOARD_$(BOARD)
 CPPDEFS += $(LUFA_OPTS)
 #CPPDEFS += -D__STDC_LIMIT_MACROS
diff --git a/Projects/Webserver/makefile b/Projects/Webserver/makefile
index 2091f8d805be5ba50bd11086382a485ae9267b76..bba6d057b200bbeb8617bacfcb337fb096c88278 100644
--- a/Projects/Webserver/makefile
+++ b/Projects/Webserver/makefile
@@ -79,8 +79,8 @@ BOARD = USBKEY
 #     calculate timings. Do NOT tack on a 'UL' at the end, this will be done
 #     automatically to create a 32-bit value in your source code.
 #
-#     This will be an integer division of F_CLOCK below, as it is sourced by
-#     F_CLOCK after it has run through any CPU prescalers. Note that this value
+#     This will be an integer division of F_USB below, as it is sourced by
+#     F_USB after it has run through any CPU prescalers. Note that this value
 #     does not *change* the processor frequency - it should merely be updated to
 #     reflect the processor speed set externally so that the code can use accurate
 #     software delays.
@@ -88,7 +88,7 @@ F_CPU = 8000000
 
 
 # Input clock frequency.
-#     This will define a symbol, F_CLOCK, in all source code files equal to the
+#     This will define a symbol, F_USB, in all source code files equal to the
 #     input clock frequency (before any prescaling is performed) in Hz. This value may
 #     differ from F_CPU if prescaling is used on the latter, and is required as the
 #     raw input clock is fed directly to the PLL sections of the AVR for high speed
@@ -98,7 +98,7 @@ F_CPU = 8000000
 #
 #     If no clock division is performed on the input clock inside the AVR (via the
 #     CPU clock adjust registers or the clock division fuses), this will be equal to F_CPU.
-F_CLOCK = $(F_CPU)
+F_USB = $(F_CPU)
 
 
 # Output format. (can be srec, ihex, binary)
@@ -217,20 +217,20 @@ CSTANDARD = -std=c99
 
 # Place -D or -U options here for C sources
 CDEFS  = -DF_CPU=$(F_CPU)UL
-CDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CDEFS += -DF_USB=$(F_USB)UL
 CDEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 CDEFS += $(LUFA_OPTS)
 
 
 # Place -D or -U options here for ASM sources
 ADEFS  = -DF_CPU=$(F_CPU)
-ADEFS += -DF_CLOCK=$(F_CLOCK)UL
+ADEFS += -DF_USB=$(F_USB)UL
 ADEFS += -DBOARD=BOARD_$(BOARD)
 ADEFS += $(LUFA_OPTS)
 
 # Place -D or -U options here for C++ sources
 CPPDEFS  = -DF_CPU=$(F_CPU)UL
-CPPDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CPPDEFS += -DF_USB=$(F_USB)UL
 CPPDEFS += -DBOARD=BOARD_$(BOARD)
 CPPDEFS += $(LUFA_OPTS)
 #CPPDEFS += -D__STDC_LIMIT_MACROS
diff --git a/Projects/XPLAINBridge/makefile b/Projects/XPLAINBridge/makefile
index 437d70ad93b973d23ca0006743ed56e95d0fbd4f..7c3b5bcb601021b40f619d7cdc51f55eb29d1fb4 100644
--- a/Projects/XPLAINBridge/makefile
+++ b/Projects/XPLAINBridge/makefile
@@ -79,8 +79,8 @@ BOARD = XPLAIN
 #     calculate timings. Do NOT tack on a 'UL' at the end, this will be done
 #     automatically to create a 32-bit value in your source code.
 #
-#     This will be an integer division of F_CLOCK below, as it is sourced by
-#     F_CLOCK after it has run through any CPU prescalers. Note that this value
+#     This will be an integer division of F_USB below, as it is sourced by
+#     F_USB after it has run through any CPU prescalers. Note that this value
 #     does not *change* the processor frequency - it should merely be updated to
 #     reflect the processor speed set externally so that the code can use accurate
 #     software delays.
@@ -88,7 +88,7 @@ F_CPU = 8000000
 
 
 # Input clock frequency.
-#     This will define a symbol, F_CLOCK, in all source code files equal to the
+#     This will define a symbol, F_USB, in all source code files equal to the
 #     input clock frequency (before any prescaling is performed) in Hz. This value may
 #     differ from F_CPU if prescaling is used on the latter, and is required as the
 #     raw input clock is fed directly to the PLL sections of the AVR for high speed
@@ -98,7 +98,7 @@ F_CPU = 8000000
 #
 #     If no clock division is performed on the input clock inside the AVR (via the
 #     CPU clock adjust registers or the clock division fuses), this will be equal to F_CPU.
-F_CLOCK = $(F_CPU)
+F_USB = $(F_CPU)
 
 
 # Output format. (can be srec, ihex, binary)
@@ -209,20 +209,20 @@ CSTANDARD = -std=c99
 
 # Place -D or -U options here for C sources
 CDEFS  = -DF_CPU=$(F_CPU)UL
-CDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CDEFS += -DF_USB=$(F_USB)UL
 CDEFS += -DBOARD=BOARD_$(BOARD) -DARCH=ARCH_$(ARCH)
 CDEFS += $(LUFA_OPTS)
 
 
 # Place -D or -U options here for ASM sources
 ADEFS  = -DF_CPU=$(F_CPU)
-ADEFS += -DF_CLOCK=$(F_CLOCK)UL
+ADEFS += -DF_USB=$(F_USB)UL
 ADEFS += -DBOARD=BOARD_$(BOARD)
 ADEFS += $(LUFA_OPTS)
 
 # Place -D or -U options here for C++ sources
 CPPDEFS  = -DF_CPU=$(F_CPU)UL
-CPPDEFS += -DF_CLOCK=$(F_CLOCK)UL
+CPPDEFS += -DF_USB=$(F_USB)UL
 CPPDEFS += -DBOARD=BOARD_$(BOARD)
 CPPDEFS += $(LUFA_OPTS)
 #CPPDEFS += -D__STDC_LIMIT_MACROS