X-Git-Url: http://git.linex4red.de/pub/USBasp.git/blobdiff_plain/ef7b6a274c9ea66d301d0b3b0d2f6de7cee2b0d1..151a1c5888f8806d7e2aaf6f29cfb6deae8321ae:/Bootloaders/Printer/BootloaderPrinter.txt?ds=sidebyside diff --git a/Bootloaders/Printer/BootloaderPrinter.txt b/Bootloaders/Printer/BootloaderPrinter.txt index 9a45fba2a..71e9b2871 100644 --- a/Bootloaders/Printer/BootloaderPrinter.txt +++ b/Bootloaders/Printer/BootloaderPrinter.txt @@ -110,6 +110,12 @@ * #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. * @@ -148,11 +154,20 @@ * +----------------------------+ FLASHEND * \endverbatim * - * 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_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. + * + * \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. + * + * \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 *