/** \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. */ /** \mainpage Printer Class USB AVR Bootloader * * \section Sec_Compat Demo Compatibility: * * The following list indicates what microcontrollers are compatible with this demo. * * \li Series 7 USB AVRs (AT90USBxxx7) * \li Series 6 USB AVRs (AT90USBxxx6) * \li Series 4 USB AVRs (ATMEGAxxU4) * \li Series 2 USB AVRs (AT90USBxx2, ATMEGAxxU2) * * \section Sec_Info USB Information: * * The following table gives a rundown of the USB utilization of this demo. * * * * * * * * * * * * * * * * * * * * * * *
USB Mode:Device
USB Class:Printer Class
USB Subclass:Printer Subclass
Relevant Standards:USBIF Printer Class Standard
Supported USB Speeds:Full Speed Mode
* * \section Sec_Description Project Description: * * This bootloader enumerates to the host as a Generic Text Only Printer device, capable of reading and parsing * "printed" plain-text Intel HEX files to load firmware onto the AVR. * * Out of the box this bootloader builds for the AT90USB1287 with an 8KB bootloader section size, and will fit * into 4KB of bootloader space. If you wish to alter this size and/or change the AVR model, you will need to * edit the MCU, FLASH_SIZE_KB and BOOT_SECTION_SIZE_KB values in the accompanying makefile. * * When the bootloader is running, the board's LED(s) will flash at regular intervals to distinguish the * bootloader from the normal user application. * * \section Sec_Running Running the Bootloader * * On the USB AVR8 devices, setting the \c HWBE device fuse will cause the bootloader to run if the \c HWB pin of * the AVR is grounded when the device is reset. * * The are two behaviours of this bootloader, depending on the device's fuses: * * If the device's BOOTRST fuse is set, the bootloader will run any time the system is reset from * the external reset pin, unless no valid user application has been loaded. To initiate the bootloader, the * device's external reset pin should be grounded momentarily. * * If the device's BOOTRST fuse is not set, the bootloader will run only if initiated via a software * jump, or if the \c HWB pin was low during the last device reset (if the \c HWBE fuse is set). * * For board specific exceptions to the above, see below. * * \subsection SSec_XPLAIN Atmel Xplain Board * Ground the USB AVR JTAG's \c TCK pin to ground when powering on the board to start the bootloader. This assumes the * \c HWBE fuse is cleared and the \c BOOTRST fuse is set as the HWBE pin is not user accessible on this board. * * \subsection SSec_Leonardo Arduino Leonardo Board * Ground \c IO13 when powering the board to start the bootloader. This assumes the \c HWBE fuse is cleared and the * \c BOOTRST fuse is set as the HWBE pin is not user accessible on this board. * * \section Sec_Installation Driver Installation * * This bootloader uses the Generic Text-Only printer drivers inbuilt into all modern operating systems, thus no * additional drivers need to be supplied for correct operation. * * \section Sec_HostApp Host Controller Application * * This bootloader is compatible with Notepad under Windows, and the command line \c lpr utility under Linux. * * \subsection SSec_Notepad Notepad (Windows) * * While most text applications under Windows will be compatible with the bootloader, the inbuilt Notepad utility * is recommended as it will introduce minimal formatting changes to the output stream. To program with Notepad, * open the target HEX file and print it to the Generic Text Only printer device the bootloader creates. * * \subsection SSec_LPR LPR (Linux) * * While the CUPS framework under Linux will enumerate the bootloader as a Generic Text-Only printer, many * applications will refuse to print to the device due to the lack of rich formatting options available. As a result, * under Linux HEX files must be printed via the low level \c lpr utility instead. * * \code * cat Mouse.hex | lpr * \endcode * * \section Sec_API User Application API * * Several user application functions for FLASH and other special memory area manipulations are exposed by the bootloader, * allowing the user application to call into the bootloader at runtime to read and write FLASH data. * * By default, the bootloader API jump table is located 32 bytes from the end of the device's FLASH memory, and follows the * following layout: * * \code * #define BOOTLOADER_API_TABLE_SIZE 32 * #define BOOTLOADER_API_TABLE_START ((FLASHEND + 1UL) - BOOTLOADER_API_TABLE_SIZE) * #define BOOTLOADER_API_CALL(Index) (void*)((BOOTLOADER_API_TABLE_START + (Index * 2)) / 2) * * void (*BootloaderAPI_ErasePage)(uint32_t Address) = BOOTLOADER_API_CALL(0); * void (*BootloaderAPI_WritePage)(uint32_t Address) = BOOTLOADER_API_CALL(1); * void (*BootloaderAPI_FillWord)(uint32_t Address, uint16_t Word) = BOOTLOADER_API_CALL(2); * uint8_t (*BootloaderAPI_ReadSignature)(uint16_t Address) = BOOTLOADER_API_CALL(3); * uint8_t (*BootloaderAPI_ReadFuse)(uint16_t Address) = BOOTLOADER_API_CALL(4); * uint8_t (*BootloaderAPI_ReadLock)(void) = BOOTLOADER_API_CALL(5); * void (*BootloaderAPI_WriteLock)(uint8_t LockBits) = BOOTLOADER_API_CALL(6); * * #define BOOTLOADER_MAGIC_SIGNATURE_START (BOOTLOADER_API_TABLE_START + (BOOTLOADER_API_TABLE_SIZE - 2)) * #define BOOTLOADER_MAGIC_SIGNATURE 0xDCFB * * #define BOOTLOADER_CLASS_SIGNATURE_START (BOOTLOADER_API_TABLE_START + (BOOTLOADER_API_TABLE_SIZE - 4)) * #define BOOTLOADER_PRINTER_SIGNATURE 0xDF20 * * #define BOOTLOADER_ADDRESS_START (BOOTLOADER_API_TABLE_START + (BOOTLOADER_API_TABLE_SIZE - 8)) * #define BOOTLOADER_ADDRESS_LENGTH 4 * \endcode * * From the application the API support of the bootloader can be detected by reading the FLASH memory bytes located at address * \c BOOTLOADER_MAGIC_SIGNATURE_START and comparing them to the value \c BOOTLOADER_MAGIC_SIGNATURE. The class of bootloader * can be determined by reading the FLASH memory bytes located at address \c BOOTLOADER_CLASS_SIGNATURE_START and comparing them * to the value \c BOOTLOADER_PRINTER_SIGNATURE. The start address of the bootloader can be retrieved by reading the bytes of FLASH * memory starting from address \c BOOTLOADER_ADDRESS_START. * * \subsection SSec_API_MemLayout Device Memory Map * The following illustration indicates the final memory map of the device when loaded with the bootloader. * * \verbatim * +----------------------------+ 0x0000 * | | * | | * | | * | | * | | * | | * | | * | | * | User Application | * | | * | | * | | * | | * | | * | | * | | * +----------------------------+ FLASHEND - BOOT_SECTION_SIZE * | | * | Bootloader Application | * | (Not User App. Accessible) | * | | * +----------------------------+ FLASHEND - 96 * | API Table Trampolines | * | (Not User App. Accessible) | * +----------------------------+ FLASHEND - 32 * | Bootloader API Table | * | (User App. Accessible) | * +----------------------------+ FLASHEND - 8 * | Bootloader ID Constants | * | (User App. Accessible) | * +----------------------------+ FLASHEND * \endverbatim * * * \section Sec_KnownIssues Known Issues: * * \par On Linux machines, new firmware fails to be sent to the device via CUPS. * Only a limited subset of normal printer functionality is exposed via the * bootloader, causing CUPS to reject print requests from applications that * are unable to handle true plain-text printing. For best results, the low * level \c lpr command should be used to print new firmware to the bootloader. * * \section Sec_Options Project Options * * The following defines can be found in this demo, which can control the demo behaviour when defined, or changed in value. * * * * * *
* None *
*/