X-Git-Url: http://git.linex4red.de/pub/USBasp.git/blobdiff_plain/359fbfe14d00ab378f85a36664820ea9ba538c3f..31022dfbe9ba7f10e9be5be85e16d2ee203d40df:/Bootloaders/CDC/BootloaderCDC.txt diff --git a/Bootloaders/CDC/BootloaderCDC.txt b/Bootloaders/CDC/BootloaderCDC.txt index 618b95d25..337b6e4a5 100644 --- a/Bootloaders/CDC/BootloaderCDC.txt +++ b/Bootloaders/CDC/BootloaderCDC.txt @@ -10,10 +10,10 @@ * * The following list indicates what microcontrollers are compatible with this demo. * - * - Series 7 USB AVRs (AT90USBxxx7) - * - Series 6 USB AVRs (AT90USBxxx6) - * - Series 4 USB AVRs (ATMEGAxxU4) - * - Series 2 USB AVRs (AT90USBxx2, ATMEGAxxU2) + * \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: * @@ -37,7 +37,7 @@ * USBIF CDC Class Standard * * - * Usable Speeds: + * Supported USB Speeds: * Full Speed Mode * * @@ -54,6 +54,9 @@ * When the bootloader is running, the board's LED(s) will flash at regular intervals to distinguish the * bootloader from the normal user application. * + * \warning THIS BOOTLOADER IS NOT SECURE. Malicious entities can recover written data, even if the device + * lockbits are set. + * * \section Sec_Installation Driver Installation * * After running this bootloader for the first time on a new computer, you will need to supply the .INF @@ -95,7 +98,9 @@ * following layout: * * \code - * #define BOOTLOADER_API_CALL(Index) (void*)(((FLASHEND - 32) + (2 * Index)) / 2) + * #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); @@ -105,21 +110,79 @@ * uint8_t (*BootloaderAPI_ReadLock)(void) = BOOTLOADER_API_CALL(5); * void (*BootloaderAPI_WriteLock)(uint8_t LockBits) = BOOTLOADER_API_CALL(6); * - * #define BOOTLOADER_MAGIC_SIGNATURE_START (FLASHEND - 2) + * #define BOOTLOADER_MAGIC_SIGNATURE_START (BOOTLOADER_API_TABLE_START + (BOOTLOADER_API_TABLE_SIZE - 2)) * #define BOOTLOADER_MAGIC_SIGNATURE 0xDCFB * - * #define BOOTLOADER_CLASS_SIGNATURE_START (FLASHEND - 4) - * #define BOOTLOADER_CDC_SIGNATURE 0xCDC1 + * #define BOOTLOADER_CLASS_SIGNATURE_START (BOOTLOADER_API_TABLE_START + (BOOTLOADER_API_TABLE_SIZE - 4)) + * #define BOOTLOADER_CDC_SIGNATURE 0xDF00 * - * #define BOOTLOADER_ADDRESS_START (FLASHEND - 8) + * #define BOOTLOADER_ADDRESS_START (BOOTLOADER_API_TABLE_START + (BOOTLOADER_API_TABLE_SIZE - 8)) * #define BOOTLOADER_ADDRESS_LENGTH 4 * \endcode * - * Bootloaders reporting a device release revision number of 1.00 or greater are bootloader API enabled. 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_CDC_SIGNATURE. - * The start address of the bootloader can be retrieved by reading the bytes of FLASH memory starting from address \c BOOTLOADER_ADDRESS_START. + * 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_CDC_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, the CDC bootloader is unstable or inaccessible. + * A change to the \c ModemManager module in many Linux distributions causes + * this module to try to take control over inserted CDC devices, corrupting the + * datastream. A UDEV rule is required to prevent this. + * See here for resolution steps. + * + * \par On Linux machines, the CDC bootloader is inaccessible. + * On many Linux systems, non-root users do not have automatic access to newly + * inserted CDC devices. Root privileges or a UDEV rule is required to gain + * access. + * See here for resolution steps. + * + * \par After loading an application, it is not run automatically on startup. + * Some USB AVR boards ship with the BOOTRST fuse set, causing the bootloader + * to run automatically when the device is reset. In most cases, the BOOTRST + * fuse should be disabled and the HWBE fuse used instead to run the bootloader + * when needed. * * \section Sec_Options Project Options * @@ -127,31 +190,31 @@ * * * - * - * - * + * + * + * * * * - * + * * * * * - * + * * * * * - * + * * * * * - * + * * * *
Define Name:Location:Description:Define Name:Location:Description:
NO_BLOCK_SUPPORTMakefile LUFA_OPTSAppConfig.hDefine to disable memory block read/write support in the bootloader, requiring all reads and writes to be made * using the byte-level commands.
NO_EEPROM_BYTE_SUPPORTMakefile LUFA_OPTSAppConfig.hDefine to disable EEPROM memory byte read/write support in the bootloader, requiring all EEPROM reads and writes * to be made using the block-level commands.
NO_FLASH_BYTE_SUPPORTMakefile LUFA_OPTSAppConfig.hDefine to disable FLASH memory byte read/write support in the bootloader, requiring all FLASH reads and writes * to be made using the block-level commands.
NO_LOCK_BYTE_WRITE_SUPPORTMakefile LUFA_OPTSAppConfig.hDefine to disable lock byte write support in the bootloader, preventing the lock bits from being set programmatically.