*
* 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 CDC Class Standard</td>
* </tr>
* <tr>
- * <td><b>Usable Speeds:</b></td>
+ * <td><b>Supported USB Speeds:</b></td>
* <td>Full Speed Mode</td>
* </tr>
* </table>
* 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 <b>THIS BOOTLOADER IS NOT SECURE.</b> 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
* 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);
* 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 <a href=https://groups.google.com/d/msg/lufa-support/CP9cy2bc8yo/kBqsOu-RBeMJ>here</a> 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 <a href=https://groups.google.com/d/msg/lufa-support/CP9cy2bc8yo/kBqsOu-RBeMJ>here</a> 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
*
*
* <table>
* <tr>
- * <td><b>Define Name:</b></td>
- * <td><b>Location:</b></td>
- * <td><b>Description:</b></td>
+ * <th><b>Define Name:</b></th>
+ * <th><b>Location:</b></th>
+ * <th><b>Description:</b></th>
* </tr>
* <tr>
* <td>NO_BLOCK_SUPPORT</td>
- * <td>Makefile LUFA_OPTS</td>
+ * <td>AppConfig.h</td>
* <td>Define to disable memory block read/write support in the bootloader, requiring all reads and writes to be made
* using the byte-level commands.</td>
* </tr>
* <tr>
* <td>NO_EEPROM_BYTE_SUPPORT</td>
- * <td>Makefile LUFA_OPTS</td>
+ * <td>AppConfig.h</td>
* <td>Define 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.</td>
* </tr>
* <tr>
* <td>NO_FLASH_BYTE_SUPPORT</td>
- * <td>Makefile LUFA_OPTS</td>
+ * <td>AppConfig.h</td>
* <td>Define 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.</td>
* </tr>
* <tr>
* <td>NO_LOCK_BYTE_WRITE_SUPPORT</td>
- * <td>Makefile LUFA_OPTS</td>
+ * <td>AppConfig.h</td>
* <td>Define to disable lock byte write support in the bootloader, preventing the lock bits from being set programmatically.</td>
* </tr>
* </table>
projects / pub / USBasp.git / blobdiff