ChangeLog.txt

/** \file
 *
 *  This file contains special DoxyGen information for the generation of the main page and other special
 *  documentation pages. It is not a project source file.
 */

 /** \page Page_ChangeLog Project Changelog
  *
  *  \section Sec_ChangeLogXXXXXX Version XXXXXX
  *
  *  <b>New:</b>
  *  - (None)
  *
  *  <b>Changed:</b>
  *  - AVRISP programmer project now has a more robust timeout system, allowing for a doubling of the software USART speed
  *    for PDI and TPI programming
  *  - Increased the speed of both software and hardware TPI/PDI programming modes of the AVRISP project
  *  - Added a timeout value to the TWI_StartTransmission() function, within which the addressed device must respond
  *
  *  <b>Fixed:</b>
  *  - Fixed software PDI/TPI programming mode in the AVRISP project not correctly toggling just the clock pin
  *  - Fixed TWI_StartTransmission() corrupting the contents of the GPIOR0 register
  *  - Fix TWI driver not aborting when faced with no response after attempting to address a device on the bus
  *
  *  \section Sec_ChangeLog100219 Version 100219
  *
  *  <b>New:</b>
  *  - Added TPI programming support for 6-pin ATTINY devices to the AVRISP programmer project (thanks to Tom Light)
  *  - Added command timeout counter to the AVRISP project so that the device no longer freezes when incorrectly connected
  *    to a target
  *  - Added new TemperatureDataLogger application, a USB data logger which writes to the device's dataflash and appears to
  *    the host as a standard Mass Storage device when inserted
  *  - Added MIDI event packing support to the MIDI Device and Host mode Class drivers, allowing for multiple MIDI events to
  *    sent or received in packed form in a single USB packet
  *  - Added new MIDI send buffer flush routines to the MIDI Device and Host mode Class drivers, to flush packed events
  *  - Added master mode hardware TWI driver for easy TWI peripheral control
  *  - Added ADC MUX masks for the standard ADC input channels on all AVR models with an ADC, altered demos to use these masks
  *    as on some models, the channel number is not identical to its single-ended ADC MUX mask
  *  - New Webserver project, a RNDIS host USB webserver using the open source uIP TCP/IP network stack and FatFS library
  *  - New BOARD value option BOARD_NONE (equivelent to not specifying BOARD) which will remove all board hardware drivers which
  *    do not adversely affect the code operation (currently only the LEDs driver)
  *  - Added keyboard modifier masks (HID_KEYBOARD_MODIFER_*) and LED report masks (KEYBOARD_LED_*) to the HID class driver and
  *    Keyboard demos
  *  - Added .5MHz recovery clock to the AVRISP programmer project when in ISP programming mode to correct mis-set fuses
  *
  *  <b>Changed:</b>
  *  - Slowed down software USART carried PDI programming in the AVRISP project to prevent transmission errors
  *  - Renamed the AVRISP project folder to AVRISP-MKII to reduce confusion
  *  - Renamed the RESET_LINE_* makefile tokens in the AVRISP MKII Project to AUX_LINE_*, as they are not always used for target
  *    reset
  *  - Changed over the MassStorageKeyboard Class driver device demo to use Start of Frame events rather than a timer to keep track
  *    of elapsed milliseconds
  *  - Inlined currently unused (but standardized) maintenance functions in the Device and Host Class drivers to save space
  *  - The XPLAINBridge project now selects between a USB to Serial bridge and a PDI programmer on startup, reading the JTAG port's
  *    TDI pin to determine which mode to use
  *  - Removed the stream example code from the Low Level VirtualSerial demos, as they were buggy and only served to add clutter
  *
  *  <b>Fixed:</b>
  *  - Fixed AVRISP project not able to enter programming mode when ISP protocol is used
  *  - Fixed AVRISP PDI race condition where the guard time between direction changes could be interpreted as a start bit
  *  - Fixed ADC_IsReadingComplete() returning an inverted result
  *  - Fixed blocking CDC streams not aborting when the host is disconnected
  *  - Fixed XPLAIN board Dataflash driver broken due to incorrect preprocessor commands
  *  - Fixed inverted XPLAIN LED driver output (LED turned on when it was supposed to be turned off, and vice-versa)
  *  - Fixed Class Driver struct interface numbers in the KeyboardMouse and VirtualSerialMouse demos (thanks to Renaud Cerrato)
  *  - Fixed invalid USB controller PLL prescaler values for the ATMEGAxxU2 controllers
  *  - Fixed lack of support for the ATMEGA32U2 in the DFU and CDC class bootloaders
  *  - Fixed Benito project not resetting the target AVR automatically when programming has completed
  *  - Fixed DFU bootloader programming not discarding the correct number of filler bytes from the host when non-aligned programming
  *    ranges are specified (thanks to Thomas Bleeker)
  *  - Fixed CDC and RNDIS host demos and class drivers - bidirectional endpoints should use two seperate pipes, not one half-duplex pipe
  *  - Fixed Pipe_IsEndpointBound() not taking the endpoint's direction into account
  *  - Fixed EEPROM and FLASH ISP programming in the AVRISP project
  *  - Fixed incorrect values of USB_CONFIG_ATTR_SELFPOWERED and USB_CONFIG_ATTR_REMOTEWAKEUP tokens (thanks to Claus Christensen)
  *  - Fixed SerialStream driver blocking while waiting for characters to be received instead of returning EOF
  *  - Fixed SerialStream driver not setting stdin to the created serial stream (thanks to Mike Alexander)
  *  - Fixed USB_GetHIDReportSize() returning the number of bits in the specified report instead of bytes
  *  - Fixed AVRISP project not extending the command delay after each successful page/word/byte program
  *  - Fixed accuracy of the SERIAL_UBBRVAL() and SERIAL_2X_UBBRVAL() macros for higher baudrates (thanks to Renaud Cerrato)
  *
  *  \section Sec_ChangeLog091223 Version 091223
  *
  *  <b>New:</b>
  *  - Added activity LED indicators to the AVRISP project to indicate when the device is busy processing a command
  *  - The USB target family and allowable USB mode tokens are now public and documented (USB_CAN_BE_*, USB_SERIES_*_AVR)
  *  - Added new XPLAIN USB to Serial Bridge project (thanks to John Steggall for initial proof-of-concept, David Prentice
  *    and Peter Danneger for revised software USART code)
  *  - Added new RNDIS Ethernet Host LowLevel demo
  *  - Added new RNDIS Ethernet Host Class Driver
  *  - Added new RNDIS Ethernet Host ClassDriver demo
  *  - Added CDC_Host_Flush() function to the CDC Host Class driver to flush sent data to the attached device
  *  - Added PDI programming support for XMEGA devices to the AVRISP programmer project (thanks to Justin Mattair)
  *  - Added support for the XPLAIN board Dataflash, with new XPLAIN_REV1 board target for the different dataflash used
  *    on the first revision boards compared to the one mounted on later revisions
  *  - Added new HID_ALIGN_DATA() macro to return the pre-retrieved value of a HID report item, left-aligned to a given datatype
  *  - Added new PreviousValue to the HID Report Parser report item structure, for easy monitoring of previous report item values
  *  - Added new EVK527 board target
  *  - Added new USB_Host_GetDeviceStringDescriptor() convenience function
  *  - Added new LEDNotification project to the library, to give a visual LED notification on new events from the host
  *  - Added new NO_DEVICE_REMOTE_WAKEUP and NO_DEVICE_SELF_POWER compile time options
  *
  *  <b>Changed:</b>
  *  - Removed code in the Keyboard demos to send zeroed reports between two reports with differing numbers of keycodes
  *    as this relied on non-standard OS driver behaviour to repeat key groups
  *  - The SCSI_Request_Sense_Response_t and SCSI_Inquiry_Response_t type defines are now part of the Mass Storage Class
  *    driver common defines, rather than being defined in the Host mode Class driver section only
  *  - The USB_MODE_HOST token is now defined even when host mode is not available
  *  - The CALLBACK_HID_Device_CreateHIDReport() HID Device Class driver callback now has a new ReportType parameter to
  *    indicate the report type to generate
  *  - All Class Drivers now return false or the "DeviceDisconnected" error code of their respective error enums when a function
  *    is called when no host/device is connected where possible
  *  - The HOST_SENDCONTROL_DeviceDisconnect enum value has been renamed to HOST_SENDCONTROL_DeviceDisconnected to be in line
  *    with the rest of the library errorcodes
  *  - Make MIDI device demos also turn off the on board LEDs if MIDI Note On messages are sent with a velocity of zero,
  *    which some devices use instead of Note Off messages (thanks to Robin Green)
  *  - The CDC demos are now named "VirtualSerial" instead to indicate the demos' function rather than its implemented USB class,
  *    to reduce confusion and to be in line with the rest of the LUFA demos
  *  - The SImage_Host_SendBlockHeader() and SImage_Host_ReceiveBlockHeader() Still Image Host Class driver functions are now public
  *
  *  <b>Fixed:</b>
  *  - Added missing CDC_Host_CreateBlockingStream() function code to the CDC Host Class driver
  *  - Fixed incorrect values for REPORT_ITEM_TYPE_* enum values causing corrupt data in the HID Host Parser
  *  - Fixed misnamed SI_Host_USBTask() and SI_Host_ConfigurePipes() functions
  *  - Fixed broken USB_GetNextDescriptor() function causing the descriptor to jump ahead double the expected amount
  *  - Fixed Pipe_IsEndpointBound() not masking the given Endpoint Address against PIPE_EPNUM_MASK
  *  - Fixed host state machine not enabling Auto VBUS mode when HOST_DEVICE_SETTLE_DELAY_MS is set to zero
  *  - Fixed misnamed Pipe_SetPipeToken() macro for setting a pipe's direction
  *  - Fixed CDCHost failing on devices with bidirectional endpoints
  *  - Fixed USB driver failing to define the PLL prescaler mask for the ATMEGA8U2 and ATMEGA16U2
  *  - Fixed HID Parser not distributing the Usage Min and Usage Max values across an array of report items
  *  - Fixed Mass Storage Host Class driver and Low Level demo not clearing the error condition if an attached device returns a
  *    STALL to a GET MAX LUN request (thanks to Martin Luxen)
  *  - Fixed TeensyHID bootloader not properly shutting down the USB interface to trigger a disconnection on the host before resetting
  *  - Fixed MassStorageHost Class driver demo not having USB_STREAM_TIMEOUT_MS compile time option set properly to prevent slow 
  *    devices from timing out the data pipes
  *  - Fixed the definition of the Endpoint_BytesInEndpoint() macro for the U4 series AVR parts
  *  - Fixed MIDI host Class driver MIDI_Host_SendEventPacket() routine not properly checking for Pipe ready before writing
  *  - Fixed use of deprecated struct initializers, removed library unused parameter warnings when compiled with -Wextra enabled
  *  - Fixed Still Image Host Class driver truncating the PIMA response code (thanks to Daniel Seibert)
  *  - Fixed USB_CurrentMode not being reset to USB_MODE_NONE when the USB interface is shut down and both Host and Device modes can be
  *    used (thanks to Daniel Levy)
  *  - Fixed TeensyHID bootloader not enumerating to the host correctly (thanks to Clint Fisher)
  *  - Fixed AVRISP project timeouts not checking for the correct timeout period (thanks to Carl Ott)
  *  - Fixed STK525 Dataflash driver using incorrect bit-shifting for Dataflash addresses (thanks to Tim Mitchell)
  *
  *  \section Sec_ChangeLog091122 Version 091122
  *
  *  <b>New:</b>
  *  - Added new Dual Role Keyboard/Mouse demo
  *  - Added new HID_HOST_BOOT_PROTOCOL_ONLY compile time token to reduce the size of the HID Host Class driver when
  *    Report protocol is not needed
  *  - Added new MIDI LowLevel and ClassDriver Host demo, add new MIDI Host Class driver
  *  - Added new CDC/Mouse ClassDriver device demo
  *  - Added new Joystick Host ClassDriver and LowLevel demos
  *  - Added new Printer Host mode Class driver
  *  - Added new Printer Host mode ClassDriver demo
  *  - Added optional support for double banked endpoints and pipes in the Device and Host mode Class drivers
  *  - Added new stream creation function to the CDC Class drivers, to easily make standard I/O streams from CDC Class driver instances
  *
  *  <b>Changed:</b>
  *  - Removed mostly useless "TestApp" demo, as it was mainly useful only for checking for sytax errors in the library
  *  - MIDI device demos now receive MIDI events from the host and display note ON messages via the board LEDs
  *  - Cleanups to the Device mode Mass Storage demo application SCSI routines
  *  - Changed Audio Class driver sample read/write functions to be inline, to reduce the number of cycles needed to transfer
  *    samples to and from the device (allowing more time for sample processing and output)
  *  - Audio class Device mode demos now work at both 16MHz and 8MHz, rather than just at 8MHz
  *  - The previous USBtoSerial demo has been moved into the projects directory, as it was just a modified CDC demo
  *  - The Endpoint/Pipe functions now use the const qualifier on the input buffer
  *  - Changed the CALLBACK_HIDParser_FilterHIDReportItem() callback to pass a HID_ReportItem_t rather than just the current
  *    item's attributes, to expose more information on the item (including it's type, collection path, etc.)
  *  - Changed MouseHostWithParser demos to check that the report items have a Mouse usage collection as a parent at some point,
  *    to prevent Joysticks from enumerating with the demo
  *  - Corrected the name of the misnamed USB_GetDeviceConfigDescriptor() function to USB_Host_GetDeviceConfigDescriptor().
  *  - Keyboard LowLevel/ClassDriver demos now support multiple simultaneous keypresses (up to 6) per report
  *
  *  <b>Fixed:</b>
  *  - Fixed PrinterHost demo returning invalid Device ID data when the attached device does not have a
  *    device ID (thanks to Andrei Krainev)
  *  - Changed LUFA_VERSION_INTEGER define to use BCD values, to make comparisons eaiser
  *  - Fixed issue in the HID Host class driver's HID_Host_SendReportByID() routine using the incorrect mode (control/pipe)
  *    to send report to the attached device
  *  - Fixed ClassDriver AudioOutput device demo not selecting an audio output mode
  *  - Fixed incorrect SampleFrequencyType value in the AudioInput and AudioOutput ClassDriver demos' descriptors
  *  - Fixed incorrect event name rule in demo/project/bootloader makefiles
  *  - Fixed HID device class driver not reselecting the correct endpoint once the user callback routines have been called
  *  - Corrected HID descriptor in the Joystick Device demos - buttons should be placed outside the pointer collection
  *  - Fixed HID report parser collection paths invalid due to misplaced semicolon in the free path item search loop
  *  - Fixed HID host Class driver report send/receive report broken when issued through the control pipe
  *  - Fixed HOST_STATE_AS_GPIOR compile time option being ignored when in host mode (thanks to David Lyons)
  *  - Fixed LowLevel Keyboard demo not saving the issues report only after it has been sent to the host
  *  - Fixed Endpoint_Write_Control_Stream_* functions not sending a terminating IN when given data Length is zero
  *
  *  \section Sec_ChangeLog090924 Version 090924
  *
  *  <b>New:</b>
  *  - Added new host mode class drivers and matching demos to the library for rapid application development
  *  - Added flag to the HID report parser to indicate if a device has multiple reports
  *  - Added new EVENT_USB_Device_StartOfFrame() event, controlled by the new USB_Device_EnableSOFEvents() and
  *    USB_Device_DisableSOFEvents() macros to give bus-synchronised millisecond interrupts when in USB device mode
  *  - Added new Endpoint_SetEndpointDirection() macro for bidirectional endpoints
  *  - Added new AVRISP project, a LUFA powered clone of the Atmel AVRISP-MKII programmer
  *  - Added ShutDown() functions for all hardware peripheral drivers, so that peripherals can be turned off after use
  *  - Added new CDC_Device_Flush() command to the device mode CDC Class driver to flush Device->Host data
  *  - Added extra masks to the SPI driver, changed SPI_Init() so that the clock polarity and sample modes can be set
  *  - Added new callback to the HID report parser, so that the user application can filter only the items it is interested
  *    in to be stored into the HIDReportInfo structure to save RAM
  *  - Added support for the officially recommended external peripheral layout for the BUMBLEB board (thanks to Dave Fletcher)
  *  - Added new Pipe_IsFrozen() macro to determine if the currently selected pipe is frozen
  *  - Added new USB_GetHIDReportSize() function to the HID report parser to retrieve the size of a given report by its ID
  *  - Added new combined Mass Storage and Keyboard demo (thanks to Matthias Hullin)
  *  
  *  <b>Changed:</b>
  *  - SetIdle requests to the HID device driver with a 0 idle period (send changes only) now only affect the requested
  *    HID interface within the device, not all HID interfaces
  *  - Added explicit attribute masks to the device mode demos' descriptors
  *  - Added return values to the CDC and MIDI class driver transmit functions
  *  - Optimized Endpoint_Read_Word_* and Pipe_Read_Word_* macros to reduce compiled size
  *  - Added non-null function parameter pointer restrictions to USB Class drivers to improve user code reliability
  *  - Added new "Common" section to the class drivers, to hold all mode-independant definitions for clarity
  *  - Moved SCSI command/sense constants into the Mass Storage Class driver, instead of the user-code
  *  - Altered the SCSI commands in the LowLevel Mass Storage Host to save on FLASH space by reducing function calls
  *  - Changed the parameters and behaviour of the USB_GetDeviceConfigDescriptor() function so that it now performs size checks
  *    and data validations internally, to simplify user code
  *  - Changed HIDParser to only zero out important values in the Parsed HID Report Item Information structure to save cycles
  *  - The HID report parser now always processed FEATURE items - HID_ENABLE_FEATURE_PROCESSING token now has no effect
  *  - The HID report parser now always ignores constant-data items, HID_INCLUDE_CONSTANT_DATA_ITEMS token now has no effect
  *  - The Benito Programmer project now has its own unique VID/PID pair allocated from the Atmel donated LUFA VID/PID pool
  *  - Add in new invalid event hook check targets to project makefiles to produce compilation errors when invalid event names
  *    are used in a project
  *  - The HID Report Parser now gives information on the total length of each report within a HID interface
  *  - The USE_NONSTANDARD_DESCRIPTOR_NAMES compile time token has been removed - there are now seperate USB_Descriptor_* and
  *    USB_StdDescriptor_* structures for both the LUFA and standardized element naming conventions so both may be used
  *
  *  <b>Fixed:</b>
  *  - Fixed possible lockup in the CDC device class driver, when the host sends data that is a multiple of the
  *    endpoint's bank
  *  - Fixed swapped parameters in the HID state memory copy call while processing a HID PUSH item in the HID report parser
  *  - Fixed memory corruption HID report parser when too many COLLECTION or PUSH items were processed
  *  - Fixed HID report parser not resetting the FEATURE item count when a REPORT ID item is encountered
  *  - Fixed USBtoSerial demos not reading in UDR1 when the USART receives data but the USB interface is not enumerated,
  *    causing continuous USART receive interrupts
  *  - Fixed misspelt event name in the Class driver USBtoSerial demo, preventing correct operation
  *  - Fixed invalid data being returned when a GetStatus request is issued in Device mode with an unhandled data recipient
  *  - Added hardware USART receive interrupt and software buffering to the Benito project to ensure received data is not
  *    missed or corrupted
  *  - Fixed Device mode HID Class driver always sending IN packets, even when nothing to report
  *  - Fixed Device mode HID Class driver not explicitly initializing the ReportSize parameter to zero before calling callback
  *    routine, so that ignored callbacks don't cause incorrect data to be sent
  *  - Fixed StillImageHost not correctly freezing and unfreezing data pipes while waiting for a response block header
  *  - Fixed error in the PrinterHost demo preventing the full page data from being sent to the attached device (thanks to John Andrews)
  *  - Fixed CDC based demos and projects' INF driver files under 64 bit versions of Windows (thanks to Ronny Hanson, Thomas Bleeker)
  *  - Re-add in missing flip, flip-ee, dfu and dfu-ee targets to project makefiles (thanks to Opendous Inc.)
  *  - Fix allowable F_CPU values comment in project makefiles to more accurately reflect the allowable values on the USB AVRs
  *  - Fixed DFU and CDC class bootloaders on the series 2 USB AVRs, corrected invalid signatures, added support for the new
  *    ATMEGAxx2 series 2 variant AVRs to the DFU bootloader
  *  - Fixed Low Level USBtoSerial demo not storing received characters (thanks to Michael Cooper)
  *  - Fixed MIDI Device Class driver not sending/receiving MIDI packets of the correct size (thanks to Thomas Bleeker)
  *
  *
  *  \section Sec_ChangeLog090810 Version 090810
  *
  *  <b>New:</b>
  *  - Added new device class drivers and matching demos to the library for rapid application development
  *  - Added new PrinterHost demo (thanks to John Andrews)
  *  - Added USB Missle Launcher project, submitted by Dave Fletcher
  *  - Added new Benito Arduino Programmer project
  *  - Added incomplete device and host mode demos for later enhancement
  *  - Updated MassStorage device block write routines to use ping-pong Dataflash buffering to increase throughput by around 30%
  *  - Error status LEDs shown when device endpoint configuration fails to complete in all demos and projects
  *  - Added new USB_Host_SetDeviceConfiguration() convenience function for easy configuration selection of devices while in USB
  *    host mode
  *  - Added new USB_Host_ClearPipeStall() convenience function to clear a stall condition on an attached device's endpoint
  *  - Added new USB_Host_GetDeviceDescriptor() convenience function to retrieve the attached device's Device descriptor
  *  - Added new Endpoint_ClearStatusStage() convenience function to assist with the status stages of control transfers
  *  - Added new USE_INTERNAL_SERIAL define for using the unique serial numbers in some AVR models as the USB device's serial number,
  *    added NO_INTERNAL_SERIAL compile time option to turn off new serial number reading code
  *  - Added new DATAFLASH_CHIP_MASK() macro to the Dataflash driver, which returns the Dataflash select mask for the given chip index
  *  - Added new HOST_STATE_WaitForDeviceRemoval host state machine state for non-blocking disabling of device communications until the
  *    device has been removed (for use when an error occurs or communications with the device have completed)
  *  - Added new FAST_STREAM_TRANSFERS compile time option for faster stream transfers via multiple bytes copied per stream loop
  *  - Added stdio stream demo code to the CDC device demos, to show how to create standard streams out of the virtual serial ports
  *  - Added new EEPROM and FLASH buffer versions of the Endpoint and Pipe stream functions
  *  - Added new USE_FLASH_DESCRIPTORS and FIXED_NUM_CONFIGURATIONS compile time options
  *  - Added support for the new ATMEGA32U2, ATMEGA16U2 and ATMEGA8U2 AVR models
  *  - Added new USB_DeviceState variable to keep track of the current Device mode USB state
  *  - Added new LEDs_ToggleLEDs() function to the LEDs driver
  *  - Added new Pipe_BoundEndpointNumber() and Pipe_IsEndpointBound() functions
  *  - Added new DEVICE_STATE_AS_GPIOR and HOST_STATE_AS_GPIOR compile time options
  *  - Added 404 Not Found errors to the webserver in the RNDIS demos to indicate invalid URLs
  *  
  *  <b>Changed:</b>
  *  - Deprecated psuedo-scheduler and removed dynamic memory allocator from the library (first no longer needed and second unused)
  *  - The device-mode CALLBACK_USB_GetDescriptor() function now has an extra parameter so that the memory space in which the requested
  *    descriptor is located can be specified. This means that descriptors can now be located in multiple memory spaces within a device.
  *  - Removed vague USB_IsConnected global - test USB_DeviceState or USB_HostState explicitly to gain previous functionality
  *  - Removed USB_IsSuspended global - test USB_DeviceState against DEVICE_STATE_Suspended instead
  *  - Extended USB_GetDeviceConfigDescriptor() routine to require the configuration number within the device to fetch
  *  - Dataflash_WaitWhileBusy() now always ensures that the dataflash is ready for the next command immediately after returning,
  *    no need to call Dataflash_ToggleSelectedChipCS() afterwards
  *  - Low level API MIDI device demo no longer blocks if a note change event is sent while the endpoint is not ready
  *  - Pipe_GetErrorFlags() now returns additional error flags for overflow and underflow errors
  *  - 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
  *  - Host mode demos now use sane terminal escape codes, so that text is always readable and events/program output is visually distinguished
  *    from oneanother using foreground colours
  *  - Internal per-device preprocessing conditions changed to per-device series rather than per-controller group for finer-grain
  *    internal control
  *  - Interrupts are no longer disabled during the processing of Control Requests on the default endpoint while in device mode
  *  - AudioOutput demos now always output to board LEDs, regardless of output mode (removed AUDIO_OUT_LEDS project option)
  *  - Removed SINGLE_DEVICE_CONFIGURATION compile time option in favour of the new FIXED_NUM_CONFIGURATIONS option so that the exact number
  *    of device configurations can be defined statically
  *  - Removed VBUS events, as they are already exposed to the user application via the regular device connection and disconnection events
  *  - Renamed and altered existing events to properly seperate out Host and Device mode events
  *
  *  <b>Fixed:</b>
  *  - Changed bootloaders to use FLASHEND rather than the existence of RAMPZ to determine if far FLASH pointers are needed to fix
  *    bootloaders on some of the USB AVR devices where avr-libc erronously defines RAMPZ
  *  - Fixes to MassStorageHost for better device compatibility (increase command timeout, change MassStore_WaitForDataReceived()
  *    to only unfreeze and check one data pipe at a time) to prevent incorrect device enumerations and freezes while trasferring data
  *  - Make Pipe_ConfigurePipe() mask the given endpoint number against PIPE_EPNUM_MASK to ensure the endpoint IN direction bit is
  *    cleared to prevent endpoint type corruption
  *  - Fixed issue opening CDC-ACM ports on hosts when the CDC device tries to send data before the host has set the line encoding
  *  - Fixed USB_OPT_MANUAL_PLL option being ignored during device disconnects on some models (thanks to Brian Dickman)
  *  - Fixed documentation mentioning Pipe_GetCurrentToken() function when correct function name is Pipe_GetPipeToken()
  *  - Fixed ADC driver for the ATMEGA32U4 and ATMEGA16U4 (thanks to Opendous Inc.)
  *  - Fixed CDCHost demo unfreezing the pipes at the point of configuration, rather than use
  *  - Fixed MassStorage demo not clearing the reset flag when a Mass Storage Reset is issued while not processing a command
  *  - Fixed USB_Host_SendControlRequest() not re-suspending the USB bus when initial device ready-wait fails
  *  - Fixed USB Pad regulator not being disabled on some AVR models when the USB_OPT_REG_DISABLED option is used
  *  - Fixed Host mode to Device mode UID change not causing a USB Disconnect event when a device was connected
  *  - Fixed Mouse/Keyboard demos not performing the correct arithmetic on the Idle period at the right times (thanks to Brian Dickman)
  *  - Fixed GenericHID failing HID class tests due to incorrect Logical Minimum and Logical Maximum values (thanks to Søren Greiner)
  *  - Fixed incorrect PIPE_EPNUM_MASK mask causing pipe failures on devices with endpoint addresses of 8 and above (thanks to John Andrews)
  *  - Fixed report data alignment issues in the MouseHostWithParser demo when X and Y movement data size is not a multiple of 8 bits
  *  - Fixed HID Report Descriptor Parser not correctly resetting internal states when a REPORT ID element is encountered
  *  - Fixed incorrect BUTTONS_BUTTON1 for the STK526 target
  *  - Fixed RNDIS demos freezing when more than one connection was attempted simultaneously, causing memory corruption
  *  - Fixed USBtoSerial demo receiving noise from the USART due to pullup not being enabled
  *
  *
  *  \section Sec_ChangeLog090605 Version 090605
  *
  *  - Fixed bug in RNDISEthernet and DualCDC demos not using the correct USB_ControlRequest structure for control request data
  *  - Fixed documentation showing incorrect USB mode support on the supported AVRs list
  *  - Fixed RNDISEthernet not working under Linux due to Linux requiring an "optional" RNDIS request which was unhandled
  *  - Fixed Mouse and Keyboard device demos not acting in accordance with the HID specification for idle periods (thanks to Brian Dickman)
  *  - Removed support for endpoint/pipe non-control interrupts; these did not act in the way users expected, and had many subtle issues
  *  - Fixed Device Mode not handling Set Feature and Clear Feature Chapter 9 requests that are addressed to the device (thanks to Brian Dickman)
  *  - Moved control endpoint interrupt handling into the library itself, enable via the new INTERRUPT_CONTROL_ENDPOINT token
  *  - Fixed CDCHost not clearing configured pipes and resetting configured pipes mask when a partially enumerated invalid CDC
  *    interface is skipped
  *  - Clarified the size of library tokens which accept integer values in the Compile Time Tokens page, values now use the smallest datatype
  *    inside the library that is able to hold their defined value to save space
  *  - Removed DESCRIPTOR_ADDRESS() macro as it was largely supurflous and only served to obfuscate code
  *  - Rewritten event system to remove all macros, to make user code clearer
  *  - Fixed incorrect ENDPOINT_EPNUM_MASK mask preventing endpoints above EP3 from being selected (thanks to Jonathan Oakley)
  *  - Removed STREAM_CALLBACK() macro - callbacks now use regular function definitions to clarify user code
  *  - Removed DESCRIPTOR_COMPARATOR() macro - comparators should now use regular function definitions to clarify user code
  *  - USB_IsConnected is now cleared before the USB_Disconnect() event is fired in response to VBUS being removed
  *  - Fixed incorrect PID value being used in the USBtoSerial project (thanks to Phill)
  *  - Deleted StdDescriptors.c, renamed USB_GetDescriptor() to CALLBACK_USB_GetDescriptor, moved ConfigDescriptor.c/.h from the
  *    LUFA/Drivers/USB/Class/ directory to LUFA/Drivers/USB/HighLevel/ in preperation for the new USB class APIs
  *  - Moved out each demos' functionality library files (e.g. Ring Buffer library) to /Lib directories for a better directory structure
  *  - Removed Tx interrupt from the USBtoSerial demo; now sends characters via polling to ensure more time for the Rx interrupt
  *  - Fixed possible enumeration errors from spinloops which may fail to exit if the USB connection is severed before the exit condition
  *    becomes true
  *
  *
  *  \section Sec_ChangeLog090510 Version 090510
  *
  *  - Added new GenericHIDHost demo
  *  - Corrections to the KeyboardHost and MouseHost demos' pipe handling to freeze and unfreeze the data pipes at the point of use
  *  - KeyboardHost, MouseHost and GenericHIDHost demos now save and restore the currently selected pipe inside the pipe ISR
  *  - Changed GenericHID device demo to use the LUFA scheduler, added INTERRUPT_DATA_ENDPOINT and INTERRUPT_CONTROL_ENDPOINT compile
  *    time options
  *  - All comments in the library, bootloaders, demos and projects have now been spell-checked and spelling mistakes/typos corrected
  *  - Added new PIMA_DATA_SIZE() define to the Still Image Host demo
  *  - Add call to MassStore_WaitForDataReceived() in MassStore_GetReturnedStatus() to ensure that the CSW has been received in the
  *    extended MSC timeout period before continuing, to prevent long processing delays from causing the MassStore_GetReturnedStatus()
  *    to early-abort (thanks to Dmitry Maksimov)
  *  - Move StdRequestType.h, StreamCallbacks.h, USBMode.h from the LowLevel USB driver directory to the HighLevel USB driver directory,
  *    where they are more suited
  *  - Removed all binary constants and replaced with decimal or hexadecimal constants so that unpatched GCC compilers can still build the
  *    code without having to be itself patched and recompiled first
  *  - Added preprocessor checks and documentation to the bootloaders giving information about missing SIGNATURE_x defines due to
  *    outdated avr-libc versions.
  *  - Added support to the CDCHost demo for devices with multiple CDC interfaces which are not the correct ACM type preceding the desired
  *    ACM CDC interface
  *  - Fixed GenericHID demo not starting USB and HID management tasks when not using interrupt driven modes (thanks to Carl Kjeldsen)
  *  - Fixed RNDISEthenet demo checking the incorrect message field for packet size constraints (thanks to Jonathan Oakley)
  *  - Fixed WriteNextReport code in the GenericHIDHost demo using incorrect parameter types and not selecting the correct endpoint
  *  - Adjusted sample CTC timer calculations in the AudioOutput and AudioInput demos to match the CTC calculations in the AVR datasheet,
  *    and to fix instances where rounding caused the endpoint to underflow (thanks to Robin Theunis)
  *  - The USB_Host_SendControlRequest() function no longer automatically selects the Control pipe (pipe 0), so that other control type
  *    pipes can be used with the function
  *  - The USB Host management task now saves and restores the currently selected pipe before and after the task completes
  *  - Fixed GenericHIDHost demo report write routine incorrect for control type requests (thanks to Andrei Krainev)
  *  - Removed Endpoint_ClearCurrentBank() and Pipe_ClearCurrentBank() in favour of new Endpoint_ClearIN(), Endpoint_ClearOUT(),
  *    Pipe_ClearIN() and Pipe_ClearOUT() macros (done to allow for the detection of packets of zero length)
  *  - Renamed *_ReadWriteAllowed() macros to *_IsReadWriteAllowed() to remain consistent with the rest of the LUFA API
  *  - Endpoint_IsSetupReceived() macro has been renamed to Endpoint_IsSETUPReceived(), Endpoint_ClearSetupReceived() macro has been
  *    renamed to Endpoint_ClearSETUP(), the Pipe_IsSetupSent() macro has been renamed to Pipe_IsSETUPSent() and the
  *    Pipe_ClearSetupSent() macro is no longer applicable and should be removed - changes made to compliment the new endpoint and pipe
  *    bank management API
  *  - Updated all demos, bootloaders and projects to use the new endpoint and pipe management APIs (thanks to Roman Thiel from Curetis AG)
  *  - Updated library doxygen documentation, added groups, changed documentation macro functions to real functions for clarity
  *  - Removed old endpoint and pipe aliased read/write/discard routines which did not have an explicit endian specifier for clarity
  *  - Removed the ButtLoadTag.h header file, as no one used for its intended purpose anyway
  *  - Renamed the main Drivers/AT90USBXXX directory to Drivers/Peripheral, renamed the Serial_Stream driver to SerialStream
  *  - Fixed CDC and USBtoSerial demos freezing where buffers were full while still transmitting or receiving (thanks to Peter Hand)
  *  - Removed "Host_" section of the function names in ConfigDescriptor.h, as most of the routines can now be used in device mode on the
  *    device descriptor
  *  - Renamed functions in the HID parser to have a "USB_" prefix and the acronym "HID" in the name
  *  - Fixed incorrect HID interface class and subclass values in the Mouse and KeyboardMouse demos (thanks to Brian Dickman)
  *  - Capitalised the "Descriptor_Search" and "Descriptor_Search_Comp" prefixes of the values in the DSearch_Return_ErrorCodes_t and
  *    DSearch_Comp_Return_ErrorCodes_t enums
  *  - Removed "ERROR" from the enum names in the endpoint and pipe stream error code enums
  *  - Renamed the USB_PowerOnErrorCodes_t enum to USB_InitErrorCodes_t, renamed the POWERON_ERROR_NoUSBModeSpecified enum value to
  *    USB_INITERROR_NoUSBModeSpecified
  *  - Renamed USB_PowerOnFail event to USB_InitFailure
  *  - Renamed OTG.h header functions to be more consistent with the rest of the library API
  *  - Changed over all deprecated GCC structure tag initializers to the standardized C99 format (thanks to Mike Alexander)
  *  - USB_HostRequest renamed to USB_ControlRequest, entire control request header is now read into USB_ControlRequest in Device mode
  *    rather than having the library pass only partially read header data to the application
  *  - The USB_UnhandledControlPacket event has had its parameters removed, in favour of accessing the new USB_ControlRequest structure
  *  - The Endpoint control stream functions now correctly send a ZLP to the host when less data than requested is sent
  *  - Fixed USB_RemoteWakeupEnabled flag never being set (the REMOTE WAKEUP Set Feature request was not being handled)
  *  - Renamed the FEATURELESS_CONTROL_ONLY_DEVICE compile-time token to CONTROL_ONLY_DEVICE
  *  - Endpoint configuration is now refined to give better output when all configurations have static inputs - removed the now useless
  *    STATIC_ENDPOINT_CONFIGURATION compile time token
  *  - Fixed SPI driver init function not clearing SPI2X bit when not needed
  *  - Fixed PREVENT ALLOW MEDIUM REMOVAL command issuing in the MassStorageHost demo using incorrect parameters (thanks to Mike Alex)
  *  - Fixed MassStorageHost demo broken due to an incorrect if statement test in MassStore_GetReturnedStatus()
  *  - Fixed reversed signature byte ordering in the CDC bootloader (thanks to Johannes Raschke)
  *  - Changed PIPE_CONTROLPIPE_DEFAULT_SIZE from 8 to 64 to try to prevent problems with faulty devices which do not respect the given
  *    wLength value when reading in the device descriptor
  *  - Fixed missing semicolon in the ATAVRUSBRF01 LED board driver code (thanks to Morten Lund)
  *  - Changed LED board driver code to define dummy LED masks for the first four board LEDs, so that user code can be compiled for boards
  *    with less than four LEDs without code modifications (thanks to Morten Lund)
  *  - Changed HWB board driver to Buttons driver, to allow for the support of future boards with more than one mounted GPIO button
  *  - Serial driver now correctly calculates the baud register value when in double speed mode
  *  - Init function of the Serial driver is now static inline to product smaller code for the common-case of static init values
  *    
  *
  *  \section Sec_ChangeLog090401 Version 090401
  *
  *  - Fixed MagStripe project configuration descriptor containing an unused (blank) endpoint descriptor
  *  - Incorporated makefile changes by Denver Gingerich to retain compatibility with stock (non-WinAVR) AVR-GCC installations
  *  - Fixed makefile EEPROM programming targets programming FLASH data in addition to EEPROM data
  *  - LUFA devices now enumerate correctly with LUFA hosts
  *  - Fixed Configuration Descriptor search routine freezing when a comparator returned a failure
  *  - Removed HID report item serial dump in the MouseHostWithParser and KeyboardHostWithParser - useful only for debugging, and
  *    slowed down the enumeration of HID devices too much
  *  - Increased the number of bits per track which can be read in the MagStripe project to 8192 when compiled for the AT90USBXXX6/7
  *  - 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
  *    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
  *  - Mass Storage Host demo now uses a USB_STREAM_TIMEOUT_MS of two seconds to maintain compatibility with poorly designed devices
  *  - Function attribute ATTR_ALWAYSINLINE renamed to ATTR_ALWAYS_INLINE to match other function attribute macro naming conventions
  *  - Added ATTR_ALWAYS_INLINE attribute to several key inlined library components, to ensure they are inlined in all circumstances
  *  - Removed SetSystemClockPrescaler() macro, the clock_prescale_set() avr-libc macro has been corrected in recent avr-libc versions
  *  - Fixed incorrect/missing control status stage transfers on demos, bootloaders and applications (thanks to Nate Lawson)
  *  - The NO_CLEARSET_FEATURE_REQUEST compile time token has been renamed to FEATURELESS_CONTROL_ONLY_DEVICE, and its function expanded
  *    to also remove parts of the Get Status chapter 9 request to further reduce code usage
  *  - Makefile updated to include output giving the currently selected BOARD parameter value
  *  - Board Dataflash driver now allows for dataflash ICs which use different shifts for setting the current page/byte address (thanks
  *    to Kenneth Clubb)
  *  - Added DataflashManager_WriteBlocks_RAM() and DataflashManager_ReadBlocks_RAM() functions to the MassStorage demo, to allow for easy
  *    interfacing with a FAT library for dataflash file level access
  *  - Corrected CDC class bootloader to fix a few bugs, changed address counter to store x2 addresses for convenience
  *  - Fixed typos in the SPI driver SPI_SPEED_FCPU_DIV_64 and SPI_SPEED_FCPU_DIV_128 masks (thanks to Markus Zocholl)
  *  - Keyboard and Mouse device demos (normal, data interrupt and fully interrupt driven) combined into unified keyboard and mouse demos
  *  - Keyboard and Mouse host demos (normal and data interrupt driven) combined into unified keyboard and mouse demos
  *  - Removed AVRISP_Programmer project due to code quality concerns
  *  - Fixed CDC demo not sending an empty packet after each transfer to prevent the host from buffering incoming data
  *  - Fixed documentation typos and preprocessor checks relating to misspellings of the USE_RAM_DESCRIPTORS token (thanks to Ian Gregg)
  *  - Fixed USBTask.h not conditionally including HostChapter9.h only when USB_CAN_BE_HOST is defined (thanks to Ian Gregg)
  *  - Fixed incorrect ADC driver init register manipulation (thanks to Tobias)
  *  - Added new GenericHID device demo application
  *  - Fixed Still Image Host SImage_SendData() function not clearing the pipe bank after sending data
  *
  *
  *  \section Sec_ChangeLog090209 Version 090209
  *
  *  - PWM timer mode in AudioOut demo changed to Fast PWM for speed
  *  - Updated Magstripe project to work with the latest hardware revision
  *  - Fixed library not responding to the BCERRI flag correctly in host mode, leading to device lockups
  *  - Fixed library handling Get Descriptor requests when not addressed as standard requests to the device or interface (thanks to
  *    Nate Lawson)
  *  - Fixed serious data corruption issue in MassStorage demo dataflash write routine
  *  - Added new NO_CLEARSET_FEATURE_REQUEST compile time token
  *  - USB task now restores previous global interrupt state after execution, rather than forcing global interrupts to be enabled
  *  - Fixed USB_DeviceEnumerationComplete event firing after each configuration change, rather than once after the initial configuration
  *  - Added ENDPOINT_DOUBLEBANK_SUPPORTED() macros to Endpoint.h, altered ENDPOINT_MAX_SIZE() to allow user to specify endpoint
  *  - ENDPOINT_MAX_ENDPOINTS changed to ENDPOINT_TOTAL_ENDPOINTS, PIPE_MAX_PIPES changed to PIPE_TOTAL_PIPES
  *  - Endpoint and Pipe non-control stream functions now ensure endpoint or pipe is ready before reading or writing
  *  - Changed Teensy bootloader to use a watchdog reset when exiting rather than a software jump
  *  - Fixed integer promotion error in MassStorage and MassStorageHost demos, corrupting read/write transfers
  *  - SPI_SendByte is now SPI_TransferByte, added new SPI_SendByte and SPI_ReceiveByte functions for fast one-way transfer
  *  - MassStorage demo changed to use new fast one-way SPI transfers to increase throughput
  *  - MassStorage handling of Mass Storage Reset class request improved
  *  - Altered MassStorage demo dataflash block read code for speed
  *  - Added USB_IsSuspended global flag
  *  - Simplified internal Dual Mode (OTG) USB library code to reduce code size
  *  - Extended stream timeout period to 100ms from 50ms
  *  - Mass Storage Host demo commands now all return an error code from the Pipe_Stream_RW_ErrorCodes_t enum
  *  - Added SubErrorCode parameter to the USB_DeviceEnumerationFailed event
  *  - VBUS drop interrupt now disabled during the manual-to-auto VBUS delivery handoff
  *  - Simplified low level backend so that device/host mode initialization uses the same code paths
  *  - Added workaround for faulty Mass Storage devices which do not implement the required GET_MAX_LUN request
  *  - Removed buggy Telnet application from the RNDIS demo
  *  - Moved Mass Storage class requests in the Mass Storage Host demo to wrapper functions in MassStoreCommands.c
  *  - Fixed incorrect SCSI command size value in the Request Sense command in MassStoreCommands.c
  *  - Added SetProtocol request to HID class non-parser Mouse and Keyboard demos to force devices to use the correct Boot Protocol
  *  - Added new "dfu" and "flip" programming targets to project makefiles
  *  - HID_PARSE_Sucessful enum member typo corrected to HID_PARSE_Successful
  *  - Changed COLLECTION item structures in the HID descriptor parser to include the collection's Usage Page value
  *  - Serial driver now sets Tx line as output, enables pullup on Rx line
  *  - Fixed smaller USB AVRs raising multiple connection and disconnection events when NO_LIMITED_CONTROLLER_CONNECT is disabled
  *  - Added HOST_DEVICE_SETTLE_DELAY_MS to give the host delay after a device is connected before it is enumerated
  *  - Fixed KeyboardHostWithParser demo linking against the wrong global variables
  *  - Completed doxygen documentation of remaining library bootloaders, demos and projects
  *  - Fixed incorrect bootloader start address in the TeensyHID bootloader
  *  - Added HWB button whole-disk ASCII dump functionality to MassStoreHost demo
  *  - Replaced printf_P(PSTR("%c"), {Variable}) calls with putchar(<Variable>) for speed and size savings
  *  - Serial driver now accepts baud rates over 16-bits in size, added double speed flag option
  *  - Fixed incorrect callback abort return value in Pipe.c
  *  - Added new flip-ee and dfu-ee makefile targets (courtesy of Opendous Inc.)
  *  - Removed reboot-on-disconnect code from the TeensyHID bootloader, caused problems on some systems
  *  - Fixed AudioOutput and AudioInput demos looping on the endpoint data, rather than processing a sample at a time and returning
  *    each time the task runs to allow for other tasks to execute
  *  - Added support for the Atmel ATAVRUSBRF01 board
  *  - Added AVRISP Programmer Project, courtesy of Opendous Inc.
  *  - Fixed CDC Host demo not searching through both CDC interfaces for endpoints
  *  - Fixed incorrect Product String descriptor length in the DFU class bootloader
  *
  *
  *  \section Sec_ChangeLog081224 Version 081224
  *
  *  - MyUSB name changed to LUFA, the Lightweight USB Framework for AVRs
  *  - Fixed Mass Storage Host demo's MassStore_SendCommand() delay in the incorrect place
  *  - Fixed USBtoSerial demo not calling ReconfigureUSART() after a change in the line encoding
  *  - Fixed infinite loop in host mode Host-to-Device control transfers with data stages
  *  - HID report parser now supports devices with multiple reports in one interface via Report IDs
  *  - Fixed RZUSBSTICK board LED driver header incorrect macro definition order causing compile errors
  *  - Calling USB_Init() when the USB interface is already configured now forces a complete interface reset
  *    and re-enumeration - fixes MyUSB DFU bootloader not switching to app code correctly when soft reset used
  *  - Fixed "No newline at end of file" warning when stream callbacks are enabled
  *  - DFU bootloader now uses fixed signature bytes per device, rather than reading them out dynamically for size
  *  - Added new FIXED_CONTROL_ENDPOINT_SIZE and USE_SINGLE_DEVICE_CONFIGURATION switches to statically define certain values to
  *    reduce compiled binary size
  *  - Added new NO_LIMITED_CONTROLLER_CONNECT switch to prevent the library from trying to determine bus connection
  *    state from the suspension and wake up events on the smaller USB AVRs
  *  - Added summary of all library compile time tokens to the documentation
  *  - Added overview of the LUFA scheduler to the documentation
  *  - Removed MANUAL_PLL_CONTROL compile time token, replaced with a mask for the USB_Init() Options parameter
  *  - CDC bootloader now uses the correct non-far or far versions of the pgm_* functions depending on if RAMPZ is defined
  *  - Doxygen documentation now contains documentation on all the projects, bootloaders and most demos included with the library
  *  - CDC bootloader now runs user application when USB disconnected rather than waiting for a hard reset
  *  - MouseHostWithParser and KeyboardHostWithParser now support multiple-report devices
  *  - RNDIS demo can now close connections correctly using the new TCP_APP_CLOSECONNECTION() macro - used in Webserver  
  *  - Fixed the DFU bootloader, no longer freezes up when certain files are programmed into an AVR, made reading/writing faster
  *  - Fixed mouse/joystick up/down movements reversed - HID mouse X/Y coordinates use a left-handed coordinate system, not a normal 
  *    right-handed system
  *  - Added stub code to the CDC and USBtoSerial demos showing how to read and set the RS-232 handshake lines - not currently used in
  *    the demos, but the example code and supporting defines are now in place
  *  - Interrupts are now disabled when processing a control request in device mode, to avoid exceeding the strict control request
  *    timing requirements.
  *  - All demos now use a central StatusUpdate() function rather than direct calls to the board LED functions, so that the demos can
  *    easily be altered to show different LED combinations (or do something else entirely) as the demo's status changes
  *  - Removed LED commands from the CDC bootloader, unused by most AVR910 programming software
  *  - Fixed RNDIS demo ICMP ping requests echoing back incorrect data
  *  - Added DHCP server code to RNDIS demo, allowing for hands-free auto configuration on any PC
  *  - Fixed DFU bootloader PID value for the ATMEGA16U4 AVR
  *  - Endpoint and Pipe configuration functions now return an error code indicating success or failure
  *  - USB Reset in device mode now resets and disables all device endpoints
  *  - Added intermediate states to the host mode state machine, reducing the USB task blocking time to no more than 1ms explicitly per
  *    invocation when in host mode
  *  - Added support for the ATMEGA32U6 microcontroller
  *  - Added STATIC_ENDPOINT_CONFIGURATION compile time option, enabled in the bootloaders to minimize space usage
  *  - Removed redundant code from the USB device GetStatus() chapter 9 processing routine
  *  - Added new TeensyHID bootloader, compatible with the Teensy HID protocol (http://www.pjrc.com/teensy/)
  *  - Versions are now numbered by release dates, rather than arbitrary major/minor revision numbers
  *  - USB_RemoteWakeupEnabled is now correctly set and cleared by SetFeature and ClearFeature requests from the host
  *  - Changed prototype of GetDescriptor, so that it now returns the descriptor size (or zero if the descriptor doesn't exist)
  *    rather than passing the size back to the caller through a parameter and returning a boolean
  *
  *
  *  \section Sec_ChangeLog153 Version 1.5.3 - Released 2nd October, 2008
  *
  *  - Fixed CDC bootloader using pgmspace macros for some descriptors inappropriately
  *  - Updated all Mouse and Keyboard device demos to include boot protocol support (now works in BIOS)
  *  - Renamed bootloader directories to remove spaces, which were causing build problems on several OSes
  *  - Removed serial number strings from all but the MassStore demo where it is required - users were not
  *    modifying the code to either omit the descriptor or use a unique serial per device causing problems
  *    when multiple units of the same device were plugged in at the same time
  *  - AudioOutput and AudioInput demos now correctly silence endpoints when not enabled by the host
  *  - Added KeyboardMouse demo (Keyboard and Mouse functionality combined into a single demo)
  *  - Added DriverStubs directory to house board level driver templates, to make MyUSB compatible custom board
  *    driver creation easier
  *  - Extended MassStorage demo to support multiple LUNs, 2 by default
  *  - Fixed incorrect device address mask, preventing the device from enumerating with addresses larger than 63
  *  - Fixed incorrect data direction mask in the GetStatus standard request, preventing it from being handled
  *  - Fixed incorrect GetStatus standard request for endpoints, now returns the endpoint STALL status correctly
  *  - Added in new USB_RemoteWakeupEnabled and USB_CurrentlySelfPowered flags rather than using fixed values
  *  - Added DualCDC demo to demonstrate the use of Interface Association Descriptors
  *  - Added pipe NAK detection and clearing API
  *  - Added pipe status change (NAK, STALL, etc.) interrupt API
  *  - Fixed MassStorageHost demo so that it no longer freezes randomly when issuing several commands in a row
  *  - Host demos configuration descriptor routines now return a unique error code when the returned data does
  *    not have a valid configuration descriptor header
  *  - Added Endpoint_WaitUntilReady() and Pipe_WaitUntilReady() functions
  *  - Stream functions now have software timeouts, timeout period can be set by the USB_STREAM_TIMEOUT_MS token
  *  - All demos now pass the USB.org automated Chapter 9 device compliance tests
  *  - All HID demos now pass the USB.org automated HID compliance tests
  *  - Polling interval of the interrupt endpoint in the CDC based demos changed to 0xFF to fix problems on Linux systems
  *  - Changed stream functions to accept a new callback function, with NO_STREAM_CALLBACKS used to disable all callbacks
  *  - Mass Storage demo dataflash management routines changed to use the endpoint stream functions		
  *  - Added AVRStudio project files for each demo in addition to the existing Programmer's Notepad master project file
  *  - Re-added call to ReconfigureUSART() in USBtoSerial SetLineCoding request, so that baud rate changes
  *    are reflected in the hardware (change was previously lost)
  *
  *
  *  \section Sec_ChangeLog152 Version 1.5.2 - Released 31st July, 2008
  *
  *  - Fixed SwapEndian_32() function in Common.h so that it now works correctly (wrong parameter types)
  *  - Updated RNDIS demo - notification endpoint is no longer blocking so that it works with faulty Linux RNDIS
  *    implementations (where the notification endpoint is ignored in favour of polling the control endpoint)
  *  - Fixed incorrect Vendor Description string return size in RNDIS demo for the OID_GEN_VENDOR_DESCRIPTION OID token
  *  - Added very basic TCP/IP stack and HTTP/TELNET servers to RNDIS demo
  *  - Fixed DFU bootloader exit causing programming software to complain about failed writes
  *  - Fixed DFU bootloader EEPROM programming mode wiping first flash page
  *  - Fixed Clear/Set Feature device standard request processing code (fixing MassStorage demo in the process)
  *  - Added support for the ATMEGA16U4 AVR microcontroller
  *  - Library licence changed from LGPLv3 to MIT license
  *
  *
  *  \section Sec_ChangeLog151 Version 1.5.1 - Released 31st July, 2008
  *
  *  - Changed host demos to enable the host function task on the firing of the USB_DeviceEnumerationComplete event
  *    rather than the USB_DeviceAttached event
  *  - HID Usage Stack now forcefully cleared after an IN/OUT/FEATURE item has been completely processed to remove
  *    any referenced but not created usages
  *  - Changed USB_INT_DisableAllInterrupts() and USB_INT_ClearAllInterrupts(), USB_Host_GetNextDescriptorOfType(),
  *    USB_Host_GetNextDescriptorOfTypeBefore(), USB_Host_GetNextDescriptorOfTypeAfter() to normal functions (from inline)
  *  - Fixed USBtoSerial demo not sending data, only receiving
  *  - Fixed main makefile to make all by default, fixed MagStripe directory case to prevent case-sensitive path problems
  *  - ConfigDescriptor functions made normal, instead of static inline
  *  - Pipe/Endpoint *_Ignore_* functions changed to *_Discard_*, old names still present as aliases
  *  - Fixed ENDPOINT_MAX_SIZE define to be correct on limited USB controller AVRs
  *  - Changed endpoint and pipe size translation routines to use previous IF/ELSE IF cascade code, new algorithmic
  *    approach was buggy and caused problems
  *  - Bootloaders now compile with -fno-inline-small-functions option to reduce code size
  *  - Audio demos now use correct endpoint sizes for full and limited controller USB AVRs, double banking in all cases
  *    to be in line with the specification (isochronous endpoints MUST be double banked)
  *  - Added Interface Association descriptor to StdDescriptors.h, based on the relevant USB2.0 ECN
  *  - Fixed MIDI demo, corrected Audio Streaming descriptor to follow the MIDI-specific AS structure
  *  - Fixed HID class demo descriptors so that the HID interface's protocol is 0x00 (required for non-boot protocol HID
  *    devices) to prevent problems on hosts expecting the boot protocol functions to be supported
  *  - Added read/write control stream functions to Endpoint.h
  *  - Fixed AudioOut demo not setting port pins to inputs on USB disconnect properly
  *  - Added RNDISEthernet demo application
  *
  *
  *  \section Sec_ChangeLog150 Version 1.5.0 - Released 10 June, 2008
  *
  *  - Fixed MIDI demo, now correctly waits for the endpoint to be ready between multiple note messages
  *  - Added CDC Host demo application
  *  - Added KeyboardFullInt demo application
  *  - Endpoint and Pipe creation routines now mask endpoint/pipe size with the size mask, to remove transaction
  *    size bits not required for the routines (improves compatibility with devices)
  *  - Fixed AudioInput demo - now correctly sends sampled audio to the host PC
  *  - Fixed AudioOutput demo once more -- apparently Windows requires endpoint packets to be >=192 bytes
  *  - Shrunk round-robbin scheduler code slightly via the use of struct pointers rather than array indexes
  *  - Fixed off-by-one error when determining if the Usage Stack is full inside the HID Report parser
  *  - Renamed Magstripe.h to MagstripeHW.h and moved driver out of the library and into the MagStripe demo folder
  *  - Added preprocessor checks to enable C linkage on the library components when used with a C++ compiler
  *  - Added Still Image Host demo application
  *  - The USB device task now restores the previously selected endpoint, allowing control requests to be transparently
  *    handled via interrupts while other endpoints are serviced through polling
  *  - Fixed device signature being sent in reverse order in the CDC bootloader
  *  - Host demos now have a separate ConfigDescriptor.c/.h file for configuration descriptor processing
  *  - HostWithParser demos now have a separate HIDReport.c/.h file for HID report processing and dumping
  *  - Removed non-mandatory commands from MassStorage demo to save space, fixed SENSE ResponseCode value
  *  - CDC demos now send empty packets after sending a full one to prevent buffering issues on the host
  *  - Updated demo descriptors to use VID/PID values donated by Atmel
  *  - Added DoxyGen documentation to the source files
  *  - Fixed Serial_IsCharReceived() definition, was previously reversed
  *  - Removed separate USB_Descriptor_Language_t descriptor, USB_Descriptor_String_t is used instead
  *  - Removed unused Device Qualifier descriptor structure
  *  - Renamed the USB_CreateEndpoints event to the more appropriate USB_ConfigurationChanged
  *  - Fixed MassStorageHost demo reading in the block data in reverse
  *  - Removed outdated typedefs in StdRequestType.h, superseded by the macro masks
  *  - Corrected OTG.h is now included when the AVR supports both Host and Device modes, for creating OTG products
  *  - USB_DeviceEnumerationComplete event is now also fired when in device mode and the host has finished its enumeration
  *  - Interrupt driven demos now properly restore previously selected endpoint when ISR is complete
  *  - USB_HOST_TIMEOUT_MS is now overridable in the user project makefile to a custom fixed timeout value
  *  - Renamed USB_Host_SOFGeneration_* macros to more friendly USB_Host_SuspendBus(), USB_Host_ResumeBus()
  *    and USB_Host_IsBusSuspended()
  *  - Renamed *_*_Is* macros to *_Is* to make all flag checking macros consistent, Pipe_SetInterruptFreq() is now
  *    Pipe_SetInterruptPeriod() to use the correct terminology
  *  - UnicodeString member of USB_Descriptor_String_t struct changed to an ordinary int array type, so that the GCC
  *    Unicode strings (prefixed with an L before the opening quotation mark) can be used instead of explicit arrays
  *    of ASCII characters
  *  - Fixed Endpoint/Pipes being configured incorrectly if the maximum endpoint/pipe size for the selected USB AVR
  *    model was given as the bank size
  *  - HID device demos now use a true raw array for the HID report descriptor rather than a struct wrapped array
  *  - Added VERSION_BCD() macro, fixed reported HID and USB version numbers in demo descriptors
  *  - Cleaned up GetDescriptor device chapter 9 handler function
  *  - Added GET_REPORT class specific request to HID demos to make them complaint to the HID class
  *  - Cleaned up setting of USB_IsInitialized and USB_IsConnected values to only when needed
  *  - Removed Atomic.c and ISRMacro.h; the library was already only compatible with recent avr-lib-c for other reasons
  *  - All demos and library functions now use USB standardized names for the USB data (bRequest, wLength, etc.)
  *  - Added USE_NONSTANDARD_DESCRIPTOR_NAMES token to switch back to the non-standard descriptor element names
  *
  *
  *  \section Sec_ChangeLog141 Version 1.4.1 - Released 5 May, 2008
  *
  *  - Enhanced KeyboardWithParser demo, now prints out pressed alphanumeric characters like the standard demo
  *  - Fixed MassStorage demo, read/writes using non mode-10 commands now work correctly
  *  - Corrected version number in Version.h
  *
  *
  *  \section Sec_ChangeLog140 Version 1.4.0 - Released 5 May, 2008
  *
  *  - Added HID Report Parser API to the library
  *  - Added Mouse and Keyboard host demo applications, using the new HID report parser engine
  *  - Added MouseFullInt demo, which demonstrates a fully interrupt (including control requests) mouse device
  *  - Fixed incorrect length value in the audio control descriptor of the AudioOutput and AudioInput demos
  *  - Added MIDI device demo application to the library
  *  - Fixed problem preventing USB devices from being resumed from a suspended state
  *  - Added new CDC class bootloader to the library, based on the AVR109 bootloader protocol
  *  - Added header to each demo application indicating the mode, class, subclass, standards used and supported speed
  *  - Functions expecting endpoint/pipe numbers are no longer automatically masked against ENDPOINT_EPNUM_MASK or
  *    PIPE_PIPENUM_MASK - this should be manually added to code which requires it
  *  - Fixed DFU class bootloader - corrected frequency of flash page writes, greatly reducing programming time
  *  - Renamed AVR_HOST_GetDeviceConfigDescriptor() to USB_Host_GetDeviceConfigDescriptor() and AVR_HOST_GetNextDescriptor()
  *    to USB_Host_GetNextDescriptor()
  *  - Added new USB_Host_GetNextDescriptorOfTypeBefore() and USB_Host_GetNextDescriptorOfTypeAfter() routines
  *  - Moved configuration descriptor routines to MyUSB/Drivers/USB/Class/, new accompanying ConfigDescriptors.c file
  *  - Added new configuration descriptor comparator API for more powerful descriptor parsing, updated host demos to use the
  *    new comparator API
  *  - Fixed MassStorageHost demo capacity printout, and changed data read/write mode from little-endian to the correct
  *    big-endian for SCSI devices
  *  - Fixed macro/function naming consistency; USB_HOST is now USB_Host, USB_DEV is now USB_Device
  *  - Added better error reporting to host demos
  *  - Added 10 microsecond delay after addressing devices in host mode, to prevent control stalls
  *
  *
  *  \section Sec_ChangeLog132 Version 1.3.2 - Released April 1st, 2008
  *
  *  - Added call to ReconfigureUSART() in USBtoSerial SetLineCoding request, so that baud rate changes
  *    are reflected in the hardware
  *  - Fixed CDC and USBtoSerial demos - Stream commands do not work for control endpoints, and the 
  *    GetLineCoding request had an incorrect RequestType mask preventing it from being processed
  *  - Improved reliability of the USBtoSerial demo, adding a busy wait while the buffer is full
  *  - Device control endpoint size is now determined from the device's descriptors rather than being fixed
  *  - Separated out SPI code into new SPI driver in AT90USBXXX driver directory
  *  - Bootloader now returns correct PID for the selected USB AVR model, not just the AT90USB128X PID
  *  - Added support for the RZUSBSTICK board
  *  - Bicolour driver removed in favour of generic LEDs driver
  *  - Added support for the ATMEGA32U4 AVR
  *  - Added MANUAL_PLL_CONTROL compile time option to prevent the USB library from manipulating the PLL
  *
  *
  *  \section Sec_ChangeLog131 Version 1.3.1 - Released March 19th 2008
  *
  *  - Fixed USB to Serial demo - class value in the descriptors was incorrect
  *  - Control endpoint size changed from 64 bytes to 8 bytes to save on USB FIFO RAM and to allow low
  *    speed mode devices to enumerate properly
  *  - USB to Serial demo data endpoints changed to dual-banked 16 byte to allow the demo to work
  *    on USB AVRs with limited USB FIFO RAM
  *  - Changed demo endpoint numbers to use endpoints 3 and 4 for double banking, to allow limited
  *    USB device controller AVRs (AT90USB162, AT90USB82) to function correctly
  *  - Updated Audio Out demo to use timer 1 for AVRs lacking a timer 3 for the PWM output
  *  - Fixed incorrect USB_DEV_OPT_HIGHSPEED entry in the Mass Storage device demo makefile
  *  - Optimized Mass Storage demo for a little extra transfer speed
  *  - Added LED indicators to the Keyboard demo for Caps Lock, Num Lock and Scroll Lock
  *  - Added Endpoint_Read_Stream, Endpoint_Write_Stream, Pipe_Read_Stream and Pipe_Write_Stream functions
  *    (including Big and Little Endian variants)
  *  - Made Dataflash functions inline for speed, removed now empty Dataflash.c driver file
  *  - Added new SetSystemClockPrescaler() macro (thanks to Joerg Wunsch)
  *  - Fixed Endpoint_ClearStall() to function correctly on full USB controller AVRs (AT90USBXXX6/7)
  *  - Endpoint_Setup_In_Clear() and Endpoint_Setup_Out_Clear() no longer set FIFOCON, in line with the
  *    directives in the datasheet
  *  - Fixed PLL prescaler defines for all AVR models and frequencies
  *  - Fixed ENDPOINT_INT_IN and ENDPOINT_INT_OUT definitions
  *  - Added interrupt driven keyboard and mouse device demos
  *  - Combined USB_Device_ClearFeature and USB_Device_SetFeature requests into a single routine for code
  *    size savings
  *  - Added missing Pipe_GetCurrentPipe() macro to Pipe.h
  *
  *
  *  \section Sec_ChangeLog130 Version 1.3.0 - Released March 7th 2008
  *
  *  - Unnecessary control endpoint config removed from device mode
  *  - Fixed device standard request interpreter accidentally processing some class-specific requests
  *  - Added USE_RAM_DESCRIPTORS and USE_EEPROM_DESCRIPTORS compile time options to instruct the library
  *    to use descriptors stored in RAM or EEPROM rather than flash memory
  *  - All demos now disable watchdog on startup, in case it has been enabled by fuses or the bootloader
  *  - USB_DEV_OPT_LOWSPEED option now works correctly
  *  - Added ability to set the USB options statically for a binary size reduction via the USE_STATIC_OPTIONS
  *    compile time define
  *  - USB_Init no longer takes a Mode parameter if compiled for a USB device with no host mode option, or
  *    if forced to a particular mode via the USB_HOST_ONLY or USB_DEVICE_ONLY compile time options
  *  - USB_Init no longer takes an Options parameter if options statically configured by USE_STATIC_OPTIONS
  *  - Endpoint_Ignore_* and Pipe_Ignore_* made smaller by making the dummy variable non-volatile so that the
  *    compiler can throw away the result more efficiently
  *  - Added in an optional GroupID value to each scheduler entry, so that groups of tasks can once again be
  *    controlled by the new Scheduler_SetGroupTaskMode() routine
  *  - Added support for AT90USB162 and AT90USB82 AVR models
  *  - Added support for the STK525 and STK526 boards
  *  - Added support for custom board drivers to be supplied by selecting the board type as BOARD_USER, and
  *    placing board drivers in {Application Directory}/Board/
  *  - PLL is now stopped and USB clock is frozen when detached from host in device mode, to save power
  *  - Joystick defines are now in synch with the schematics - orientation will be rotated for the USBKEY
  *  - Fixed USB_DEV_IsUSBSuspended() - now checks the correct register
  *  - Fixed data transfers to devices when in host mode
  *  - Renamed USB_DEV_OPT_HIGHSPEED to USB_DEV_OPT_FULLSPEED and USB_HOST_IsDeviceHighSpeed() to
  *    USB_HOST_IsDeviceFullSpeed() to be in line with the official USB speed names (to avoid confusion with
  *    the real high speed mode, which is unavailable on the USB AVRs)
  *
  *
  *  \section Sec_ChangeLog120 Version 1.2.0 - Released February 4th, 2008
  *
  *  - Added USB_DeviceEnumerationComplete event for host mode
  *  - Added new Scheduler_Init routine to preprepare the scheduler, so that tasks can be started and
  *    stopped before the scheduler has been started (via Scheduler_Start)
  *  - Connection events in both Device and Host mode are now interrupt-driven, allowing the USB management
  *    task to be stopped when the USB is not connected to a host or device
  *  - All demos updated to stop the USB task when not in use via the appropriate USB events
  *  - Mass Storage Host demo application updated to function correctly with all USB flash disks
  *  - Mass Storage Host demo application now prints out the capacity and number of LUNs in the attached
  *    device, and prints the first block as hexadecimal numbers rather than ASCII characters
  *  - Endpoint and Pipe clearing routines now clear the Endpoint/Pipe interrupt and status flags
  *  - Shifted error handling code in the host enum state machine to a single block, to reduce code complexity
  *  - Added in DESCRIPTOR_TYPE, DESCRIPTOR_SIZE and DESCRIPTOR_CAST macros to make config descriptor processing
  *    clearer in USB hosts and DESCRIPTOR_ADDRESS for convenience in USB devices
  *  - Added in alloca macro to common.h, in case the user is using an old version of avr-lib-c missing the macro
  *
  *
  *  \section Sec_ChangeLog130 Version 1.1.0 - Released January 25th 2008
  *
  *  - Fixed DCONNI interrupt being enabled accidentally after a USB reset
  *  - Fixed DDISCI interrupt not being disabled when a device is not connected
  *  - Added workaround for powerless pullup devices causing false disconnect interrupts
  *  - Added USB_DeviceEnumerationFailed event for Host mode
  *  - AVR_HOST_GetDeviceConfigDescriptor routine no longer modifies ConfigSizePtr if a valid buffer
  *    pointer is passed
  *  - Added ALLOCABLE_BYTES to DynAlloc, and added code to make the size of key storage variables
  *    dependant on size of memory parameters passed in via the user project's makefile
  *  - Fixed incorrect device reset routine being called in USBTask
  *  - Devices which do not connect within the standard 300mS are now supported
  *  - Removed incorrect ATTR_PURE from Scheduler_SetTaskMode(), which was preventing tasks from being
  *    started/stopped, as well as USB_InitTaskPointer(), which was breaking dual device/host USB projects
  *  - Changed scheduler to use the task name rather than IDs for setting the task mode, eliminating the
  *    need to have a task ID list
  *  - ID transistion interrupt now raises the appropriate device/host disconnect event if device attached
  *  - Fixed double VBUS change (and VBUS -) event when detatching in device mode
  *  - Added ability to disable ANSI terminal codes by the defining of DISABLE_TERMINAL_CODES in makefile
  *  - Removed return from ConfigurePipe and ConfigureEndpoint functions - use Pipe_IsConfigured() and 
  *    Endpoint_IsConfigured() after calling the config functions to determine success
  */