ChangeLog.txt

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 /** \page Page_ChangeLog Project Changelog
  *
  *  \section Sec_ChangeLogXXXXXX Version XXXXXX
  *  <b>New:</b>
  *  - Core:
  *   - None
  *  - Library Applications:
  *   - Added User Application APIs to the CDC and DFU class bootloaders
  *
  *  <b>Changed:</b>
  *  - Core:
  *   - None
  *  - Library Applications:
  *   - None
  *
  *  <b>Fixed:</b>
  *  - Core:
  *   - None
  *  - Library Applications:
  *   - None
  *
  *  \section Sec_ChangeLog111009 Version 111009
  *  <b>New:</b>
  *  - Core:
  *   - Added USE_LUFA_CONFIG_HEADER compile time option to include a LUFAConfig.h header in the user director for LUFA configuration
  *     tokens as an alternative to tokens defined in the project makefile
  *   - Added new USB_Host_SetInterfaceAltSetting() convenience function for the selection of an interface's alternative setting
  *   - Added Audio class control request definitions
  *   - Added new CALLBACK_Audio_Device_GetSetEndpointProperty() callback to the Audio Device Class driver to allow for endpoint control manipulations
  *     such as data sample rates
  *   - Added support for the Audio class GET STATUS request in the Audio Device Class driver so that it is correctly ACKed when sent by the host
  *   - Added new EVENT_Audio_Device_StreamStartStop() event to the Audio Device Class driver to detect stream start/stop events
  *   - Added board driver support for the Busware TUL board
  *   - Added board hardware driver support for the EVK1100 board
  *   - Added board hardware driver support for the EVK1104 board
  *   - Added new Host mode Audio Class driver
  *   - Added new SPI_GetCurrentMode() function to the SPI peripheral driver
  *   - Added RingBuffer_GetFreeCount() function to the Ring Buffer driver
  *   - Added new HID_Host_SetIdlePeriod() function to the HID Host Class driver
  *   - Added new USB_Host_ConfigurationNumber global variable to indicate the selected configuration in an attached device
  *   - Added new USB_Host_GetDeviceStatus() function to the host standard request function set
  *   - Added AVR USB XMEGA architecture port (currently incomplete/experimental)
  *   - Added new STRINGIFY() and STRINGIFY_EXPANDED() convenience macros
  *   - Added new JTAG_DISABLE() macro for the AVR8 architecture
  *   - Added Device Qualifier standard descriptor structure definitions USB_StdDescriptor_DeviceQualifier_t and USB_Descriptor_DeviceQualifier_t
  *  - Library Applications:
  *   - Added RNDIS device mode to the Webserver project
  *   - Added new incomplete AndroidAccessoryHost Host LowLevel demo
  *   - Added new HIDReportViewer project
  *   - Added new MediaControl project
  *   - Added new AudioInputHost Host ClassDriver demo
  *   - Added new AudioOutputHost Host ClassDriver demo
  *   - Added new AudioInputHost Host LowLevel demo
  *   - Added new AudioOutputHost Host LowLevel demo
  *   - Added new "checksource" target to all library project makefiles
  *   - Added new VTARGET_USE_INTERNAL_REF configuration option to the AVRISP-MKII clone project (thanks to Volker Bosch)
  *
  *  <b>Changed:</b>
  *  - Core:
  *   - Altered the definition of the USB_Audio_Descriptor_Format_t descriptor so that the user is now responsible for supplying
  *     the supported audio sampling rates, to allow for multiple audio interfaces with different numbers of supported rates and/or
  *     continuous sample rates
  *   - Pipe_BoundEndpointNumber() has been renamed to Pipe_GetBoundEndpointAddress(), and now returns the correct endpoint direction
  *     as part of the endpoint address
  *   - Renamed global state variables that are specific to a certain USB mode to clearly indicate which mode the variable relates to,
  *     by changing the USB_* prefix to USB_Device_* or USB_Host_*
  *   - Removed the HOST_STATE_WaitForDeviceRemoval and HOST_STATE_Suspended host state machine states, as these are no longer required
  *   - Altered the USB_Host_SetDeviceConfiguration() function to update the global Host state machine state and the new
  *     USB_Host_ConfigurationNumber global as required
  *   - Added endian correcting code to the library USB class drivers for multiple architecture support
  *   - Removed the ENDPOINT_DESCRIPTOR_DIR_* macros, replaced by ENDPOINT_DIR_* instead
  *   - Renamed the JTAG_DEBUG_ASSERT() macro to JTAG_ASSERT()
  *   - Added variable number of axis to HID_DESCRIPTOR_JOYSTICK() for multi-axis joysticks above just X and Y
  *   - Renamed USB_Host_ClearPipeStall() to USB_Host_ClearEndpointStall() as the function works on an endpoint address within the attached device,
  *     and not a Pipe within the host
  *   - The MS_Host_ResetMSInterface() now performs a full Mass Storage reset sequence to prevent data corruption in the event of a device
  *     lock up or timeout (thanks to David Lyons)
  *   - Added endian-correction to the CDC driver's Line Encoding control request handlers.
  *  - Library Applications:
  *   - Modified the Low Level and Class Driver AudioInput and AudioOutput demos to support multiple audio sample rates
  *   - Updated all host mode demos and projects to use the EVENT_USB_Host_DeviceEnumerationComplete() event callback for device configuration
  *     instead of manual host state machine manipulations in the main application task
  *   - Changed the reports in the GenericHID device demos to control the board LEDs, to reduce user confusion over the callback routines
  *   - Added reliability patches to the AVRISP-MKII Clone project's ISP and PDI/TPI protocols (thanks to Justin Mattair)
  *
  *  <b>Fixed:</b>
  *  - Core:
  *   - Large number of documentation and code comment corrections (thanks to Andrey from Microsin.ru)
  *   - Fixed possibility of the AVR's SPI interface being pulled out of master mode if the /SS pin is a input and pulled low (thanks
  *     to Andrey from Microsin.ru)
  *   - Fixed compile error when FIXED_CONTROL_ENDPOINT_SIZE compile time option was disabled, and a USE_*_DESCRIPTORS compile time
  *     option was not enabled on the AVR8s
  *   - Fixed lack of C++ compatibility in some internal header files causing compile errors when using LUFA in C++ projects
  *   - Fixed error in the pipe unordered allocation algorithm for the AVR8 devices breaking compatibility with some devices
  *   - Fixed USB_USBTask not being called internally in stream transfers between packets when Partial Stream Transfers are used
  *   - Fixed swapped TWI_ADDRESS_READ and TWI_ADDRESS_WRITE values
  *   - Fixed TWI_ReadPacket() not releasing the TWI bus on read completion
  *   - Fixed optimization error in the HID Parser item value USB_SetHIDReportItemInfo() and USB_GetHIDReportItemInfo() routines if the report item was
  *     \c NULL (which should be allowable according to the API)
  *   - Fixed HID Parser CALLBACK_HIDParser_FilterHIDReportItem() callback function not being passed a cacheable report item pointer
  *   - Fixed HID Parser's largest report size bit count not including the size of the last parsed report item
  *   - Fixed HID host driver's largest HID report size count corrupt when the number of report bits exceeds 255
  *  - Library Applications:
  *   - Fixed incorrect signature in the CDC and DFU class bootloaders for the ATMEGA8U2
  *   - Fixed KeyboardHost and KeyboardHostWithParser demos displaying incorrect values when numerical keys were pressed
  *   - Fixed compile errors in the incomplete BluetoothHost demo application (thanks to Timo Lindfors)
  *   - Fixed incorrect Dataflash buffer use in the DataflashManager_WriteBlocks_RAM() function of several demos/projects (thanks to Jeremy Willden)
  *   - Fixed incorrect logging interval (always 500ms longer than requested) in the TempDataLogger project
  *   - Fixed incorrect buffer size check in the USBtoSerial project (thanks to Yuri A Nikiforov)
  *   - Fixed port state table corruption in the TCP layer of the RNDIS Ethernet device demos
  *
  *  \section Sec_ChangeLog110528 Version 110528
  *  <b>New:</b>
  *  - Core:
  *   - Added new ORDERED_EP_CONFIG compile time option to restrict endpoint/pipe configuration to ascending order
  *     in exchange for a smaller compiled program binary size
  *   - Added a new general RingBuff.h miscellaneous ring buffer library driver header
  *   - Added new GCC_FORCE_POINTER_ACCESS() macro to correct GCC's mishandling of struct pointer accesses
  *   - Added new GCC_MEMORY_BARRIER() macro to prevent instruction reordering across boundaries
  *   - Added basic driver example use code to the library documentation
  *   - Added new Endpoint_Null_Stream() and Pipe_Null_Stream() functions
  *   - Added new ADC_GET_CHANNEL_MASK() convenience macro
  *   - Added new HID report item macros (with HID_RI_ prefix) to allow for easy creation and editing of HID report descriptors
  *   - Added new HID_DESCRIPTOR_MOUSE(), HID_DESCRIPTOR_KEYBOARD(), HID_DESCRIPTOR_JOYSTICK() and HID_DESCRIPTOR_VENDOR() macros
  *     for easy automatic creation of basic USB HID device reports
  *   - Added new MAX() and MIN() convenience macros
  *   - Added new Serial_SendData() function to the Serial driver
  *   - Added board driver support for the Sparkfun ATMEGA8U2 breakout board
  *   - Added TWI baud rate prescaler and bit length parameters to the TWI_Init() function (thanks to Thomas Herlinghaus)
  *   - Internal restructuring for eventual multiple architecture ports
  *   - Added AVR32 UC3 architecture port (currently incomplete/experimental)
  *   - Added new architecture independent functions to enable, disable, save and restore the Global Interrupt Enable flags
  *   - Added new RNDIS Device Class Driver packet send and receive functions
  *  - Library Applications:
  *   - Added ability to write protect Mass Storage disk write operations from the host OS
  *   - Added new MIDIToneGenerator project
  *   - Added new KeyboardMouseMultiReport Device ClassDriver demo
  *   - Added new VirtualSerialMassStorage Device ClassDriver demo
  *   - Added HID class bootloader, compatible with a modified version of the command line Teensy loader from PJRC.com
  *   - Added LED flashing to the CDC and DFU class bootloaders to indicate when they are running
  *
  *  <b>Changed:</b>
  *  - Core:
  *   - Unordered Endpoint/Pipe configuration is now allowed once again by default via the previous reconfig workaround
  *   - Refactored Host mode Class Driver *_Host_ConfigurePipes() routines to be more space efficient when compiled
  *   - Added new *_ENUMERROR_PipeConfigurationFailed error codes for the *_Host_ConfigurePipes() routines
  *   - The USARTStream global is now public and documented in the SerialStream module, allowing for the serial USART
  *     stream to be accessed via its handle rather than via the implicit stdout and stdin streams
  *   - The FAST_STREAM_TRANSFERS compile time option has been removed due to lack of use and low cost/benefit ratio
  *   - Altered all endpoint/pipe stream transfers so that the new BytesProcessed parameter now points to a location
  *     where the number of bytes in the transfer that have been completed can be stored (or NULL if entire transaction
  *     should be performed in one chunk)
  *   - The NO_STREAM_CALLBACKS compile time option has now been removed due to the new partial stream transfer feature
  *   - Changed over all project and demo HID report descriptors to use the new HID report item macros
  *   - Moved the HIDParser.c source file to the LUFA/Drivers/USB/Class/Common/ directory from the LUFA/Drivers/USB/Class/Host/
  *   - Added support to the HID parser for extended USAGE items that contain the usage page as well as the usage index
  *   - Removed the SerialStream driver, rolled functionality into the regular Serial peripheral driver via the new
  *     Serial_CreateStream() and Serial_CreateBlockingStream() functions
  *   - Renamed the low level Serial byte send/receive functions, to be consistent with the CDC class driver byte functions
  *   - Altered the behaviour of the serial byte reception function so that is is non-blocking, and now returns a negative
  *     value if no character is received (to remain consistent with the CDC class driver byte reception routines)
  *   - Renamed the PRNT_Host_SendString(), CDC_Host_SendString() and CDC_Device_SendString() functions to *_SendData(), and
  *     added new versions of the *_SendString() routines that expect a null terminated string instead
  *   - Renamed all driver termination *_ShutDown() functions to the more logical name *_Disable()
  *   - Reduced latency for executing the Start-Of-Frame events (if enabled in the user application)
  *   - 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
  *   - Renamed all low level Endpoint_Read_*, Endpoint_Write_* and Endpoint_Discard_* functions to use the number of bits instead of
  *     a symbolic size (Byte, Word, DWord) so that the function names are applicable and correct across all architectures
  *   - Renamed all low level Pipe_Read_*, Pipe_Write_* and Pipe_Discard_* functions to use the number of bits instead of
  *     a symbolic size (Byte, Word, DWord) so that the function names are applicable and correct across all architectures
  *   - Separated out board drivers by architecture in the library internals for better organisation
  *  - 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
  *   - Combined page and word ISP programming mode code in the AVRISP-MKII clone project to reduce compiled size and
  *     increase maintainability of the code
  *   - Changed over library projects to use the new general ring buffer library driver module
  *   - Added new high level TWI packet read/write commands, altered behaviour of the TWI_StartTransmission() function
  *   - Changed TempDataLogger project's DS1307 driver to simplify the function interface and prevent a possible race condition
  *   - Changed AVRISP-MKII project to use the Watchdog interrupt for command timeouts, to reduce CPU usage and free timer 0
  *     for other uses
  *   - Updated the software USART code in the XPLAIN Bridge application so that the incoming bits are sampled at their mid-point
  *     instead of starting point, to give maximum reliability (thanks to Anton Staaf)
  *
  *  <b>Fixed:</b>
  *  - Core:
  *   - Fixed broken USBFOO board drivers due to missing BOARD_USBFOO define
  *   - Fixed HID host class driver incorrectly binding to HID devices that do not have an OUT endpoint
  *   - Fixed incorrect definition of the HID_KEYBOARD_SC_D constant in the HID class driver (thanks to Opendous Inc.)
  *   - Fixed incorrect definition of the HID_KEYBOARD_SC_RIGHT_ARROW constant in the HID class driver (thanks to Joby Taffey)
  *   - Fixed incorrect endpoint initialisation order in the several device demos (thanks to Rick Drolet)
  *   - Fixed inverted Minimus board LEDs
  *   - Fixed incorrect byte ordering in the Audio_Device_WriteSample24 function (thanks to WZab)
  *   - Fixed several functions in the Host mode Still Image Class driver returning an error code from the incorrect
  *     error code enum (thanks to Daniel Seibert)
  *   - Fixed ReportID not being removed from the feature/out report data array in the HID class driver when Report IDs are used
  *   - Fixed incorrect BUTTONS_BUTTON1 definition for the Minimus board
  *   - Fixed Still Image Host class driver exiting the descriptor search routine prematurely if the data pipes (but not event pipe)
  *     is found
  *   - Fixed missing call to Pipe_SetInfiniteINRequests() in the Pipe_ConfigurePipe() routine
  *   - Fixed Remote Wakeup broken on the AVRs due to the mechanism only operating when the SUSPI bit is set (thanks to Holger Steinhaus)
  *   - Fixed possible invalid program execution when in host mode if corrupt descriptor lengths are supplied by the attached device
  *  - Library Applications:
  *   - Fixed Benito project discarding incoming data from the USB virtual serial port when the USART is busy
  *   - Fixed broken DFU bootloader, added XPLAIN support for bootloader start when XCK jumpered to ground
  *   - Fixed broken HID_REQ_GetReport request handler in the Low Level GenericHID demo
  *   - Fixed possible lost data in the XPLAINBridge, USBtoSerial and Benito projects when the host exceeds the packet
  *     timeout period on received packets as set by USB_STREAM_TIMEOUT_MS (thanks to Justin Rajewski)
  *   - Fixed possible programming problem in the AVRISP-MKII clone project when programming specific patterns into a target
  *     memory space that is only byte (not page) addressable
  *   - Fixed errors in the incomplete Test and Measurement device demo preventing proper operation (thanks to Pavel Plotnikov)
  *   - Fixed programming errors in the AVRISP-MKII project when the programming packet is a round multiple of the endpoint bank
  *     size under avrdude (thanks to Steffan Woltjer)
  *
  *
  *  \section Sec_ChangeLog101122 Version 101122
  *  <b>New:</b>
  *  - Core:
  *    - Added new SCSI_ASENSE_NOT_READY_TO_READY_CHANGE constant to the Mass Storage class driver, to indicate when a previously
  *      not ready removable medium has now become ready for the host's use (thanks to Martin Degelsegger)
  *    - Moved the Pipe and Endpoint stream related code to two new USB library core source files EndpointStream.c and PipeStream.c
  *    - Added new USB_Device_GetFrameNumber() and USB_Host_GetFrameNumber() functions to retrieve the current USB frame number
  *    - Added new USB_Host_EnableSOFEvents(), USB_Host_DisableSOFEvents() and EVENT_USB_Host_StartOfFrame() for the user application
  *      handling of USB Start of Frame events while in USB Host mode
  *    - Added new PRNT_Host_BytesReceived(), PRNT_Host_ReceiveByte(), PRNT_Host_SendByte() and PRNT_Host_Flush() functions to the
  *      Print Host Class driver
  *    - Added class specific descriptor alternative struct type defines with standard USB-IF element naming
  *    - Added new project makefile template to the library and moved board driver stub files into in a new "CodeTemplates" directory
  *    - Added board hardware driver support for the Adafruit U4 breakout board
  *    - Added board hardware driver support for the Arduino Uno development board
  *    - Added board hardware driver support for the Blackcat USB JTAG board (thanks to the PSGroove team)
  *    - Added board hardware driver support for the Busware BUI development board
  *    - Added board hardware driver support for the Busware CUL V3 868MHZ radio board (thanks to Dirk Tostmann)
  *    - Added board hardware driver support for the Kernel Concepts USBFOO development board
  *    - Added board hardware driver support for the Linnix UDIP development board
  *    - Added board hardware driver support for the Olimex AVR-USB-162 development board (thanks to Steve Fawcett)
  *    - Added board hardware driver support for the Maximus board (thanks to the PSGroove team)
  *    - Added board hardware driver support for the Microsin AVR-USB162 breakout board
  *    - Added board hardware driver support for the Minimus board (thanks to the PSGroove team)
  *    - Added new NO_CLASS_DRIVER_AUTOFLUSH compile time option to disable automatic flushing of interfaces when the USB management
  *      tasks for each driver is called
  *    - Added standard keyboard HID report scan-code defines (thanks to Laszlo Monda)
  *    - Added new Pipe_GetBusyBanks(), Endpoint_GetBusyBanks() and Endpoint_AbortPendingIN() functions
  *  - Library Applications:
  *    - Added default test tone generation mode to the Device mode AudioInput demos
  *    - Added new NO_BLOCK_SUPPORT, NO_EEPROM_BYTE_SUPPORT, NO_FLASH_BYTE_SUPPORT and NO_LOCK_BYTE_WRITE_SUPPORT compile time options to the
  *      CDC class bootloader
  *    - Added new XCK_RESCUE_CLOCK_ENABLE compile time option to the AVRISP-MKII clone programmer project (thanks to Tom Light)
  *
  *  <b>Changed:</b>
  *  - Core:
  *    - Removed complicated logic for the Endpoint_ConfigureEndpoint() function to use inlined or function called versions
  *      depending of if the given bank size is a compile time constant, as the compiler does a better job of optimizing
  *      with basic code
  *    - Changed the signature of the CALLBACK_USB_GetDescriptor() callback function so that the descriptor pointer is const, to remove
  *      the need for extra casting inside the callback (thanks to Jonathan Kollasch)
  *    - Reduced HOST_DEVICE_SETTLE_DELAY_MS to 1000ms down from 1500ms to improve device compatibility while in USB Host mode
  *    - Removed the EVENT_USB_InitFailure() event, not specifying a USB mode correctly now defaults to UID selection mode
  *    - Renamed and moved class driver common constant definitions to make the naming scheme more uniform
  *    - Moved the USB mode specifier constants into a new enum, so that they are semantically related to one another
  *    - Renamed ENDPOINT_DOUBLEBANK_SUPPORTED() to ENDPOINT_BANKS_SUPPORTED() and changed it to return the maximum number of supported banks for
  *      the given endpoint
  *    - Better algorithm to extract and convert the internal device serial number into a string descriptor (if present)
  *    - All USB class drivers are now automatically included when LUFA/Drivers/USB.h is included, and no longer need to be separately included
  *    - The MIDI class drivers now automatically flushes the MIDI interface when the MIDI class driver's USBTask() function is called
  *    - Renamed the EVENT_USB_Device_UnhandledControlRequest() event to EVENT_USB_Device_ControlRequest() as it is now fired before the library
  *      request handlers, not afterwards
  *  - Library Applications:
  *    - Changed over all device demos to use a clearer algorithm for the configuring of the application's endpoints
  *    - Added missing DataflashManager_CheckDataflashOperation() function to the MassStorageKeyboard demo, removed redundant
  *      SCSI_Codes.h file as these values are part of the MassStorage Class Driver
  *    - Added compile time error to the AVRISP-MKII project when built for the U4 chips, as the default VTARGET detection ADC channel
  *      does not exist on these chips (thanks to Marco)
  *    - Changed all Device mode LowLevel demos and Device Class drivers so that the control request is acknowledged and any data
  *      transferred as quickly as possible without any processing in between sections, so that long callbacks or event handlers will
  *      not break communications with the host by exceeding the maximum control request stage timeout period
  *    - Changed over all demos, drivers and internal functions to use the current frame number over the Start of Frame flag where possible
  *      to free up the Start of Frame flag for interrupt use in the user application
  *    - All project makefiles now correctly clean intermediate build files from assembly and C++ sources (thanks to Daniel Czigany)
  *    - Changed default value for the reset polarity parameter in the AVRISP-MKII project so that it defaults to active low drive
  *    - Changed configuration descriptor parser for all host mode projects and class drivers to ensure better compatibility with devices
  *    - All LowLevel demos changed to use the constants and types defined in the USB class drivers
  *    - Changed AudioInput and AudioOutput demos to reload the next sample via an interrupt rather than polling the sample timer
  *    - Rescue clock of the AVRISP-MKII moved to the AVR's OCR1A pin, so that the clock can be generated at all times
  *    - Changed ClassDriver MIDI demos to process all incoming events in a loop until the bank becomes empty rather than one at a time
  *    - Changed LowLevel MIDI demos to only clear the incoming event bank once it has become empty to support packed event packets
  *
  *  <b>Fixed:</b>
  *  - Core:
  *    - Fixed USB_GetHIDReportItemInfo() function modifying the given report item's data when the report item does not exist
  *      within the supplied report of a multiple report HID device
  *    - Fixed critical pipe/endpoint memory allocation issue where the bank memory address space could be silently overlapped
  *      in the USB controller if the endpoints or pipes were allocated in anything other than ascending order (thanks to Martin Degelsegger)
  *    - Added LEDs_ToggleLEDs() function to several board LED drivers which were missing it (thanks to Andrei Krainev)
  *    - Fixed SET FEATURE and CLEAR FEATURE control requests directed at an unconfigured endpoint causing request timeouts
  *    - Fixed USB_Host_ClearPipeStall() incorrectly determining the endpoint direction from the currently selected pipe
  *    - Fixed JTAG_DEBUG_POINT() and JTAG_DEBUG_BREAK() macros not compiling under pure C99 standards mode
  *    - Fixed endpoint selection within the CALLBACK_HID_Device_CreateHIDReport() callback function causing broken GET REPORT requests
  *    - Fixed incorrect command name for EEPROM memory programming in the makefile dfu-ee target
  *    - Fixed incorrect LEDs_ChangeLEDs() function in the Benito board LED driver
  *    - Fixed incorrect USB_DeviceState value when unconfiguring the device without an address set
  *    - Fixed SPI driver not explicitly setting /SS and MISO pins as inputs when SPI_Init() is called
  *    - Fixed random enumeration failure while in device mode due to interrupts causing the Set Address request to exceed maximum timings
  *    - Fixed MIDI_Host_Flush() not aborting early when the specified MIDI host interface was not configured
  *    - Fixed MIDI class driver send routines silently discarding packets if the endpoint or pipe is busy (thanks to Robin Green)
  *  - Library Applications:
  *    - Fixed MassStorage based demos and projects resetting the SCSI sense values before the command is executed, leading to
  *      missed SCSI sense values when the host retrieves the sense key (thanks to Martin Degelsegger)
  *    - Fixed USBtoSerial and Benito project SetLineEncoding calls failing if the USART is busy, due to the RX ISR delaying the control
  *      request handler
  *    - Fixed LowLevel PrinterHost demo not sending control requests to the attached printer with the correct printer interface wIndex value
  *    - Fixed incorrect signature reported in the CDC class bootloader for the ATMEGA32U2
  *    - Fixed BootloaderCDC project failing on some operating systems due to removed Line Encoding options (thanks to Alexey Belyaev)
  *    - Fixed broken FLASH/EEPROM programming in the AVRISP-MKII clone project when writing in non-paged mode and the polling byte cannot be used
  *    - Fixed ISR definition conflict in the XPLAIN bridge between the software UART and the AVRISP-MKII ISP modules
  *    - Fixed USBtoSerial and XPLAINBridge demos discarding data from the PC if the send buffer becomes full
  *    - Fixed broken input in the MagStripe reader project due to an incorrect HID report descriptor
  *    - Fixed incorrect PollingIntervalMS values in the demo/project/bootloader endpoint descriptors (thanks to MCS Electronics)
  *    - Fixed AVRISP-MKII clone project not starting the target's program automatically after exiting TPI programming mode
  *
  *
  *  \section Sec_ChangeLog100807 Version 100807
  *  <b>New:</b>
  *  - Added new ADC_DisableChannel() function (thanks to Mich Davis)
  *  - Added new VTARGET_REF_VOLTS and VTARGET_SCALE_FACTOR compile time defines to the AVRISP-MKII programmer project to set
  *    the VTARGET reference voltage and scale factor
  *  - Added new pgm_read_ptr() macro to Common.h for reading of pointers out of flash memory space
  *  - Added new SWAPENDIAN_16() and SWAPENDIAN_32() macros to Common.h for statically initialized variables at compile time
  *  - Added new Drivers/USB/LowLevel/Device.c file to house Device mode specific functions that are more complicated than simple macros
  *  - Added new AVRStudio 4 project files for all library demos, projects and bootloaders
  *  - Added ability to set the serial baud rate via the user's terminal in the XPLAINBridge project
  *  - Added new LUFA module variables for the different source modules in the core library makefile to simplify project makefiles
  *  - Added start of a new Test and Measurement class demo (thanks to Peter Lawrence)
  *  - Added new SPI_ORDER_* data order masks to the SPI peripheral driver
  *  - Added support to the AVRISP-MKII project for ISP speeds slower than 125KHz via a new software SPI driver
  *  - Added support for the new button/LED on the latest model USBTINY-MKII
  *
  *  <b>Changed:</b>
  *  - The RingBuff library code has been replaced in the XPLAINBridge, Benito and USBtoSerial projects with an ultra lightweight
  *    ring buffer to help improve the reliability of the projects
  *  - The EEPROM stream read/write functions now use eeprom_update_byte() instead of eeprom_write_byte(), so that only
  *    changed bytes are written to EEPROM to preserve its lifespan
  *  - Changed over the AVRISP-MKII and TemperatureDataLogger projects to use eeprom_update_byte() when writing non-volatile
  *    parameters to EEPROM to preserve its lifespan
  *  - Removed unused line encoding data and control requests from the CDC Bootloader code, to save space
  *  - Renamed SERIAL_STREAM_ASSERT() macro to STDOUT_ASSERT()
  *  - The USB_Device_IsRemoteWakeupSent() and USB_Device_IsUSBSuspended() macros have been deleted, as they are now obsolete
  *  - Rewrote the implementation of the SwapEndian_16() and SwapEndian_32() functions so that they compile down in most instances to
  *    minimal loads and stores rather than complicated shifts
  *  - The software UART in the XPLAINBridge has been largely altered to try to improve upon its performance and reliability
  *  - The USBtoSerial and Benito projects now flushes received data via a flush timer, so that several bytes can be transmitted at once
  *  - Removed the automated checking of event names in the demo, project and bootloader makefiles due to inconsistencies between the
  *    behaviour of the command line tools used to perform the check on each platform
  *  - Internal USB driver source files renamed and moved to ease future possible architecture ports
  *  - All internal pseudo-function macros have been converted to true inline functions for type-safety and readability
  *  - Changed LED indicator masks for the AVRISP-MKII project, so that there are defined roles for each LED
  *  - Altered the CDC Device and Host Class drivers' receive byte routines, so that no data is indicated by the function returning a
  *    negative value (thanks to Andreas Paulin)
  *  - Added auto flushing of OUT data to the CDC Host Class driver's USBTask function to automatically flush the send pipe buffer
  *
  *  <b>Fixed:</b>
  *  - Fixed AVRISP project sending a LOAD EXTENDED ADDRESS command to 128KB AVRs after programming or reading from
  *    the last page of FLASH (thanks to Gerard Sexton)
  *  - Fixed AVRISP project not sending a full erase-and-write EEPROM command to XMEGA targets when writing to the EEPROM
  *    instead of the split write-only command (thanks to Tim Margush)
  *  - Fixed RNDISEthernet demos crashing when calculating checksums for Ethernet/TCP packets of more than ~500 bytes due to
  *    an overflow in the checksum calculation loop (thanks to Kevin Malec)
  *  - Fixed XPLAINBridge project not correctly reading the XMEGA's supply voltage when reporting back to the host
  *  - Fixed incorrect signature for the ATMEGA32U2 in the DFU bootloader (thanks to Axel Rohde)
  *  - Fixed internal device serial not being accessible on the ATMEGAXXU2 AVRs (thanks to Axel Rohde)
  *  - Fixed void pointer arithmetic in ConfigDescriptor.h breaking C++ compatibility (thanks to Michael Hennebry)
  *  - Fixed broken PDI EEPROM Section Erase functionality in the AVRISP-MKII project
  *  - Fixed USB_Device_SendRemoteWakeup() not working when the USB clock was frozen during USB bus suspend (thanks to Brian Dickman)
  *  - Fixed occasional lockup of the AVRISP project due to the timeout extension code incorrectly extending the timeout in
  *    PDI and TPI programming modes infinitely
  *  - Fixed HID device class driver still using PrevReportINBuffer for GetReport control requests even when it has been
  *    set to NULL by the user application (thanks to Axel Rohde)
  *  - Fixed MIDI_Device_SendEventPacket() not correctly waiting for the endpoint to become ready (thanks to Robin Green)
  *  - Fixed Benito and USBtoSerial projects not turning off the USART before reconfiguring it, which could cause incorrect
  *    operation to occur (thanks to Bob Paddock)
  *  - Fixed Serial peripheral driver not turning off the USART before reconfiguring it, which would cause incorrect operation
  *    to occur (thanks to Bob Paddock)
  *  - Fixed software application start command broken in the DFU class bootloader when dfu-programmer is used due to application
  *    start address corruption
  *
  *
  *  \section Sec_ChangeLog100513 Version 100513
  *  <b>New:</b>
  *  - Added incomplete MIDIToneGenerator project
  *  - Added new Relay Controller Board project (thanks to OBinou)
  *  - Added board hardware driver support for the Teensy, USBTINY MKII, Benito and JM-DB-U2 lines of third party USB AVR boards
  *  - Added new ATTR_NO_INIT variable attribute for global variables that should not be automatically cleared on startup
  *  - Added new ENDPOINT_*_BusSuspended error code to the Endpoint function, so that the stream functions early-abort if the bus
  *    is suspended before or during a transfer
  *  - Added new EVENT_CDC_Device_BreakSent() event and CDC_Host_SendBreak() function to the Device and Host CDC Class drivers
  *  - Added ReportType parameter to the HID device class driver CALLBACK_HID_Device_ProcessHIDReport() function so that FEATURE
  *    reports from the host to the device can be correctly processed
  *  - Added ReportType parameter to the HID host class driver HID_Host_SendReportByID() function so that FEATURE reports can be
  *    issued to the attached device
  *
  *  <b>Changed:</b>
  *  - AVRISP programmer project now has a more robust timeout system
  *  - Added a timeout value to the TWI_StartTransmission() function, within which the addressed device must respond
  *  - Webserver project now uses the board LEDs to indicate the current IP configuration state
  *  - Added ENABLE_TELNET_SERVER compile time option to the Webserver project to disable the TELNET server if desired
  *  - Increased throughput of the USBtoSerial demo on systems that send multiple bytes per packet (thanks to Opendous Inc.)
  *  - Double bank CDC endpoints in the XPLAIN Bridge project, re-enable JTAG once the mode selection pin has been sampled.
  *  - Standardized the naming scheme given to configuration descriptor sub-elements in the Device mode demos, bootloaders
  *    and projects
  *  - All Class Driver Host mode demos now correctly set the board LEDs to READY once the enumeration process has completed
  *  - Added LIBUSB_FILTERDRV_COMPAT compile time option to the AVRISP programmer project to make the code compatible with Windows
  *    builds of avrdude at the expense of AVRStudio compatibility
  *  - Removed two-step endpoint/pipe bank clear and switch sequence for smaller, faster endpoint/pipe code
  *  - The USB_Init() function no longer calls sei() - the user is now responsible for enabling interrupts when they are ready
  *    for them to be enabled (thanks to Andrei Krainev)
  *  - The Audio_Device_IsSampleReceived() and Audio_Device_IsReadyForNextSample() functions are now inline, to reduce overhead
  *  - Removed the cast to uint16_t on the set baud rate in the USBtoSerial project, so that the higher >1M baud rates can be
  *    selected (thanks to Steffan Woltjer)
  *  - Removed software PDI and TPI emulation from the AVRISP-MKII clone project as it was very buggy and slow - PDI and TPI must
  *    now be implemented via separate programming headers
  *  - The CDC class bootloader now uses a watchdog reset rather than a soft-reset when exited to ensure that all hardware is
  *    properly reset to their defaults
  *  - Device mode class driver callbacks are now fired before the control request status stage is sent to prevent the host from
  *    timing out if another request is immediately fired and the device has a lengthy callback routine
  *  - The TeensyHID bootloader has been removed, per request from Paul at PJRC
  *  - The LIBUSB_FILTERDRV_COMPAT compile time option in the XPLAINBridge and AVRISP-MKII projects has been renamed
  *    LIBUSB_DRIVER_COMPAT, as it applies to all software on all platforms using the libUSB driver
  *
  *  <b>Fixed:</b>
  *  - Fixed possible device lockup when INTERRUPT_CONTROL_ENDPOINT is enabled and the control endpoint is not properly
  *    selected when the ISR completes
  *  - Fixed AVRISP-MKII clone project not correctly issuing LOAD EXTENDED ADDRESS commands when the extended address
  *    boundary is crossed during programming or read back (thanks to Gerard Sexton)
  *  - Fixed warnings when building the AVRISP-MKII clone project with the ENABLE_XPROG_PROTOCOL compile time option disabled
  *  - 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
  *  - Fixed TWI driver not aborting when faced with no response after attempting to address a device on the bus
  *  - Fixed ADC routines not correctly returning the last result when multiple channels were read
  *  - Fixed ADC routines failing to read the extended channels (Channels 8 to 13, Internal Temperature Sensor) on the
  *    U4 series USB AVR parts
  *  - Fixed LowLevel MassStorage demo broken on the U2 series USB AVRs due to unsupported double-banked endpoint modes used
  *  - Fixed compilation error in the AudioInput demos when MICROPHONE_BIASED_TO_HALF_RAIL is defined (thanks to C. Scott Ananian)
  *  - Fixed incorrect definition of HID_ALIGN_DATA() causing incorrect HID report item data alignment
  *  - Fixed Still Image Host class driver not resetting the transaction ID when a new session is opened, fixed driver not sending
  *    a valid session ID to the device
  *  - Removed invalid dfu and flip related targets from the bootloaders - bootloaders can only be replaced with an external programmer
  *  - Fixed Set/Clear Feature requests directed to a non-configured endpoint not returning a stall to the host
  *  - Fixed HID Device Class Driver not allocating a temporary buffer when the host requests a report via the control endpoint and the
  *    user has set the PrevReportINBuffer driver configuration element to NULL (thanks to Lars Noschinski)
  *  - Fixed device state not being reset to DEVICE_STATE_Default if the host sets a 0x00 device address
  *  - Fixed device not stalling configuration requests before the device's address has been set
  *  - Fixed possibility of internal signature retrieval being corrupted if an interrupt occurs during a signature byte
  *    read (thanks to Andrei Krainev)
  *  - Fixed device state not being reset back to the default state if the host sets the address to 0
  *  - Fixed Set Configuration requests not being stalled until the host has set the device's address
  *  - Fixed Host mode HID class driver not sending the correct report type when HID_Host_SendReportByID() was called and the
  *    HID_HOST_BOOT_PROTOCOL_ONLY compile time option is set
  *  - Fixed INTERRUPT_CONTROL_ENDPOINT compile time option preventing other interrupts from occurring while the control endpoint
  *    request is being processed, causing possible lockups if a USB interrupt occurs during a transfer
  *  - Remove incorrect Abstract Call Management class specific descriptor from the CDC demos, bootloaders and projects
  *
  *
  *  \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 (equivalent 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 separate 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 baud rates (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 key codes
  *    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 error codes
  *  - 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 syntax 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 key presses (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 easier
  *  - 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-synchronized 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-independent 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 separate 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 misspelled 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 Missile 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 pseudo-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_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
  *    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 favor 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 separate out Host and Device mode events
  *  - All demos switched over from GNU99 standards mode to C99 standards mode, to reduce the dependencies on GCC-only language extensions
  *
  *  <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 erroneously 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 transferring 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 Soren 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 pull-up 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 superfluous 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 preparation 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 spin-loops 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 favor 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)
  *  - Capitalized 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 favor 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_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
  *  - 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 pull-up 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