+ * \section Sec_HostApp Host Controller Application
+ *
+ * This bootloader is compatible with the open source application AVRDUDE, Atmel's AVRPROG, or other
+ * applications implementing the AVR109 protocol, which is documented on the Atmel website as an application
+ * note.
+ *
+ * \subsection SSec_AVRDude AVRDUDE (Windows, Mac, Linux)
+ *
+ * AVRDude is a free, cross-platform and open source command line programmer for Atmel and third party AVR
+ * programmers. It is available on the the Windows platform as part of the "WinAVR" package, or on other systems
+ * either from a build from the official source code, or in many distributions as a precompiled binary package.
+ *
+ * To load a new HEX file with AVRDude, specify "AVR109" as the programmer, with the allocated COM port. On Windows
+ * platforms this will be a COMx port name:
+ * \code
+ * avrdude -c AVR109 -p at90usb1287 -P COM0 -U flash:w:Mouse.hex
+ * \endcode
+ *
+ * On Linux systems, this will typically be a /dev/ttyACMx port name:
+ * \code
+ * avrdude -c AVR109 -p at90usb1287 -P /dev/ttyACM0 -U flash:w:Mouse.hex
+ * \endcode
+ *
+ * Refer to the AVRDude project documentation for additional usage instructions.
+ *
+ * \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_CDC_SIGNATURE 0xDF00
+ *
+ * #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_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.
+ *
projects / pub / USBasp.git / blobdiff