Bootloaders/Printer/BootloaderPrinter.txt

   1 /** \file
   2  *
   3  *  This file contains special DoxyGen information for the generation of the main page and other special
   4  *  documentation pages. It is not a project source file.
   5  */
   6
   7 /** \mainpage Printer Class USB AVR Bootloader
   8  *
   9  *  \section Sec_Compat Demo Compatibility:
  10  *
  11  *  The following list indicates what microcontrollers are compatible with this demo.
  12  *
  13  *  \li Series 7 USB AVRs (AT90USBxxx7)
  14  *  \li Series 6 USB AVRs (AT90USBxxx6)
  15  *  \li Series 4 USB AVRs (ATMEGAxxU4)
  16  *  \li Series 2 USB AVRs (AT90USBxx2, ATMEGAxxU2)
  17  *
  18  *  \section Sec_Info USB Information:
  19  *
  20  *  The following table gives a rundown of the USB utilization of this demo.
  21  *
  22  *  <table>
  23  *   <tr>
  24  *    <td><b>USB Mode:</b></td>
  25  *    <td>Device</td>
  26  *   </tr>
  27  *   <tr>
  28  *    <td><b>USB Class:</b></td>
  29  *    <td>Printer Class</td>
  30  *   </tr>
  31  *   <tr>
  32  *    <td><b>USB Subclass:</b></td>
  33  *    <td>Printer Subclass</td>
  34  *   </tr>
  35  *   <tr>
  36  *    <td><b>Relevant Standards:</b></td>
  37  *    <td>USBIF Printer Class Standard</td>
  38  *   </tr>
  39  *   <tr>
  40  *    <td><b>Supported USB Speeds:</b></td>
  41  *    <td>Full Speed Mode</td>
  42  *   </tr>
  43  *  </table>
  44  *
  45  *  \section Sec_Description Project Description:
  46  *
  47  *  This bootloader enumerates to the host as a Generic Text Only Printer device, capable of reading and parsing
  48  *  "printed" plain-text Intel HEX files to load firmware onto the AVR.
  49  *
  50  *  Out of the box this bootloader builds for the AT90USB1287 with an 8KB bootloader section size, and will fit
  51  *  into 4KB of bootloader space. If you wish to alter this size and/or change the AVR model, you will need to
  52  *  edit the MCU, FLASH_SIZE_KB and BOOT_SECTION_SIZE_KB values in the accompanying makefile.
  53  *
  54  *  When the bootloader is running, the board's LED(s) will flash at regular intervals to distinguish the
  55  *  bootloader from the normal user application.
  56  *
  57  *  \section Sec_Installation Driver Installation
  58  *
  59  *  This bootloader uses the Generic Text-Only printer drivers inbuilt into all modern operating systems, thus no
  60  *  additional drivers need to be supplied for correct operation.
  61  *
  62  *  \section Sec_HostApp Host Controller Application
  63  *
  64  *  This bootloader is compatible with Notepad under Windows, and the command line \c lpr utility under Linux.
  65  *
  66  *  \subsection SSec_Notepad Notepad (Windows)
  67  *
  68  *  While most text applications under Windows will be compatible with the bootloader, the inbuilt Notepad utility
  69  *  is recommended as it will introduce minimal formatting changes to the output stream. To program with Notepad,
  70  *  open the target HEX file and print it to the Generic Text Only printer device the bootloader creates.
  71  *
  72  *  \subsection SSec_LPR LPR (Linux)
  73  *
  74  *  While the CUPS framework under Linux will enumerate the bootloader as a Generic Text-Only printer, many
  75  *  applications will refuse to print to the device due to the lack of rich formatting options available. As a result,
  76  *  under Linux HEX files must be printed via the low level \c lpr utility instead.
  77  *
  78  *  \code
  79  *  cat Mouse.hex | lpr
  80  *  \endcode
  81  *
  82  *  \section Sec_API User Application API
  83  *
  84  *  Several user application functions for FLASH and other special memory area manipulations are exposed by the bootloader,
  85  *  allowing the user application to call into the bootloader at runtime to read and write FLASH data.
  86  *
  87  *  By default, the bootloader API jump table is located 32 bytes from the end of the device's FLASH memory, and follows the
  88  *  following layout:
  89  *
  90  *  \code
  91  *  #define BOOTLOADER_API_TABLE_SIZE          32
  92  *  #define BOOTLOADER_API_TABLE_START         ((FLASHEND + 1UL) - BOOTLOADER_API_TABLE_SIZE)
  93  *  #define BOOTLOADER_API_CALL(Index)         (void*)((BOOTLOADER_API_TABLE_START + (Index * 2)) / 2)
  94  *
  95  *  void    (*BootloaderAPI_ErasePage)(uint32_t Address)               = BOOTLOADER_API_CALL(0);
  96  *  void    (*BootloaderAPI_WritePage)(uint32_t Address)               = BOOTLOADER_API_CALL(1);
  97  *  void    (*BootloaderAPI_FillWord)(uint32_t Address, uint16_t Word) = BOOTLOADER_API_CALL(2);
  98  *  uint8_t (*BootloaderAPI_ReadSignature)(uint16_t Address)           = BOOTLOADER_API_CALL(3);
  99  *  uint8_t (*BootloaderAPI_ReadFuse)(uint16_t Address)                = BOOTLOADER_API_CALL(4);
 100  *  uint8_t (*BootloaderAPI_ReadLock)(void)                            = BOOTLOADER_API_CALL(5);
 101  *  void    (*BootloaderAPI_WriteLock)(uint8_t LockBits)               = BOOTLOADER_API_CALL(6);
 102  *
 103  *  #define BOOTLOADER_MAGIC_SIGNATURE_START   (BOOTLOADER_API_TABLE_START + (BOOTLOADER_API_TABLE_SIZE - 2))
 104  *  #define BOOTLOADER_MAGIC_SIGNATURE         0xDCFB
 105  *
 106  *  #define BOOTLOADER_CLASS_SIGNATURE_START   (BOOTLOADER_API_TABLE_START + (BOOTLOADER_API_TABLE_SIZE - 4))
 107  *  #define BOOTLOADER_PRINTER_SIGNATURE       0xDF20
 108  *
 109  *  #define BOOTLOADER_ADDRESS_START           (BOOTLOADER_API_TABLE_START + (BOOTLOADER_API_TABLE_SIZE - 8))
 110  *  #define BOOTLOADER_ADDRESS_LENGTH          4
 111  *  \endcode
 112  *
 113  *  From the application the API support of the bootloader can be detected by reading the FLASH memory bytes located at address
 114  *  \c BOOTLOADER_MAGIC_SIGNATURE_START and comparing them to the value \c BOOTLOADER_MAGIC_SIGNATURE. The class of bootloader
 115  *  can be determined by reading the FLASH memory bytes located at address \c BOOTLOADER_CLASS_SIGNATURE_START and comparing them
 116  *  to the value \c BOOTLOADER_PRINTER_SIGNATURE. The start address of the bootloader can be retrieved by reading the bytes of FLASH
 117  *  memory starting from address \c BOOTLOADER_ADDRESS_START.
 118  *
 119  *  \subsection SSec_API_MemLayout Device Memory Map
 120  *  The following illustration indicates the final memory map of the device when loaded with the bootloader.
 121  *
 122  *  \verbatim
 123  *  +----------------------------+ 0x0000
 124  *  |                            |
 125  *  |                            |
 126  *  |                            |
 127  *  |                            |
 128  *  |                            |
 129  *  |                            |
 130  *  |                            |
 131  *  |                            |
 132  *  |      User Application      |
 133  *  |                            |
 134  *  |                            |
 135  *  |                            |
 136  *  |                            |
 137  *  |                            |
 138  *  |                            |
 139  *  |                            |
 140  *  +----------------------------+ FLASHEND - BOOT_SECTION_SIZE
 141  *  |                            |
 142  *  |   Bootloader Application   |
 143  *  | (Not User App. Accessible) |
 144  *  |                            |
 145  *  +----------------------------+ FLASHEND - 96
 146  *  |   API Table Trampolines    |
 147  *  | (Not User App. Accessible) |
 148  *  +----------------------------+ FLASHEND - 32
 149  *  |    Bootloader API Table    |
 150  *  |   (User App. Accessible)   |
 151  *  +----------------------------+ FLASHEND - 8
 152  *  |   Bootloader ID Constants  |
 153  *  |   (User App. Accessible)   |
 154  *  +----------------------------+ FLASHEND
 155  *  \endverbatim
 156  *
 157  *
 158  *  \section Sec_KnownIssues Known Issues:
 159  *
 160  *  \par On Linux machines, new firmware fails to be sent to the device via CUPS.
 161  *  Only a limited subset of normal printer functionality is exposed via the
 162  *  bootloader, causing CUPS to reject print requests from applications that
 163  *  are unable to handle true plain-text printing. For best results, the low
 164  *  level \c lpr command should be used to print new firmware to the bootloader.
 165  *
 166  *  \par After loading an application, it is not run automatically on startup.
 167  *  Some USB AVR boards ship with the BOOTRST fuse set, causing the bootloader
 168  *  to run automatically when the device is reset. In most cases, the BOOTRST
 169  *  fuse should be disabled and the HWBE fuse used instead to run the bootloader
 170  *  when needed.
 171  *
 172  *  \section Sec_Options Project Options
 173  *
 174  *  The following defines can be found in this demo, which can control the demo behaviour when defined, or changed in value.
 175  *
 176  *  <table>
 177  *   <tr>
 178  *    <td>
 179  *     None
 180  *    </td>
 181  *   </tr>
 182  *  </table>
 183  */
 184