*
* 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:
*
* <td>USBIF DFU Class Standard, Atmel USB Bootloader Datasheet</td>
* </tr>
* <tr>
- * <td><b>Usable Speeds:</b></td>
- * <td>Full Speed Mode</td>
+ * <td><b>Supported USB Speeds:</b></td>
+ * <td>Low Speed Mode \n
+ * Full Speed Mode</td>
* </tr>
* </table>
*
* This bootloader enumerates to the host as a DFU Class device, allowing for DFU-compatible programming
* software to load firmware onto the AVR.
*
- * Out of the box this bootloader builds for the USB1287, and should fit into 4KB of bootloader space. If
- * you wish to enlarge this space and/or change the AVR model, you will need to edit the BOOT_START and MCU
- * values in the accompanying makefile.
+ * 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.
* 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.
*
- * \note The APIs exposed by the DFU class bootloader are \b NOT compatible with the API exposed by the official Atmel DFU bootloader.
+ * \warning The APIs exposed by the DFU class bootloader are \b NOT compatible with the API exposed by the official Atmel DFU bootloader.
*
* 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_START(Index) (void*)(((FLASHEND - 32) + (2 * Index)) / 2)
- * void (*BootloaderAPI_ErasePage)(uint32_t Address) = BOOTLOADER_API_START(0);
- * void (*BootloaderAPI_WritePage)(uint32_t Address) = BOOTLOADER_API_START(1);
- * void (*BootloaderAPI_FillWord)(uint32_t Address, uint16_t Word) = BOOTLOADER_API_START(2);
- * uint8_t (*BootloaderAPI_ReadSignature)(uint16_t Address) = BOOTLOADER_API_START(3);
- * uint8_t (*BootloaderAPI_ReadFuse)(uint16_t Address) = BOOTLOADER_API_START(4);
- * uint8_t (*BootloaderAPI_ReadLock)(void) = BOOTLOADER_API_START(5);
- * void (*BootloaderAPI_WriteLock)(uint8_t LockBits) = BOOTLOADER_API_START(6);
+ * #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_CDC_SIGNATURE 0xDFB1
+ *
+ * #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_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_Options Project Options
*
* The following defines can be found in this demo, which can control the demo behaviour when defined, or changed in value.
* </tr>
* <tr>
* <td>SECURE_MODE</td>
- * <td>BootloaderDFU.h</td>
- * <td>If defined to true, the bootloader will not accept any memory commands other than a chip erase on start-up, until an
+ * <td>AppConfig.h</td>
+ * <td>If defined to \c true, the bootloader will not accept any memory commands other than a chip erase on start-up, until an
* erase has been performed. This can be used in conjunction with the AVR's lockbits to prevent the AVRs firmware from
- * being dumped by unauthorized persons.</td>
+ * being dumped by unauthorized persons. When false, all memory operations are allowed at any time.</td>
* </tr>
* </table>
*/
projects / pub / USBasp.git / blobdiff