summaryrefslogtreecommitdiffstats
path: root/lib/lufa/Bootloaders/Printer/BootloaderPrinter.txt
blob: d9aa79686f772c6b01f4d60257cd260f1c946299 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
/** \file
 *
 *  This file contains special DoxyGen information for the generation of the main page and other special
 *  documentation pages. It is not a project source file.
 */

/** \mainpage Printer Class USB AVR Bootloader
 *
 *  \section Sec_Compat Demo Compatibility:
 *
 *  The following list indicates what microcontrollers are compatible with this demo.
 *
 *  \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:
 *
 *  The following table gives a rundown of the USB utilization of this demo.
 *
 *  <table>
 *   <tr>
 *    <td><b>USB Mode:</b></td>
 *    <td>Device</td>
 *   </tr>
 *   <tr>
 *    <td><b>USB Class:</b></td>
 *    <td>Printer Class</td>
 *   </tr>
 *   <tr>
 *    <td><b>USB Subclass:</b></td>
 *    <td>Printer Subclass</td>
 *   </tr>
 *   <tr>
 *    <td><b>Relevant Standards:</b></td>
 *    <td>USBIF Printer Class Standard</td>
 *   </tr>
 *   <tr>
 *    <td><b>Supported USB Speeds:</b></td>
 *    <td>Full Speed Mode</td>
 *   </tr>
 *  </table>
 *
 *  \section Sec_Description Project Description:
 *
 *  This bootloader enumerates to the host as a Generic Text Only Printer device, capable of reading and parsing
 *  "printed" plain-text Intel HEX files to load firmware onto the AVR.
 *
 *  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.
 *
 *  \section Sec_Running Running the Bootloader
 *
 *  On the USB AVR8 devices, setting the \c HWBE device fuse will cause the bootloader to run if the \c HWB pin of
 *  the AVR is grounded when the device is reset.
 *
 *  The are two behaviours of this bootloader, depending on the device's fuses:
 *
 *  <b>If the device's BOOTRST fuse is set</b>, the bootloader will run any time the system is reset from
 *  the external reset pin, unless no valid user application has been loaded. To initiate the bootloader, the
 *  device's external reset pin should be grounded momentarily.
 *
 *  <b>If the device's BOOTRST fuse is not set</b>, the bootloader will run only if initiated via a software
 *  jump, or if the \c HWB pin was low during the last device reset (if the \c HWBE fuse is set).
 *
 *  For board specific exceptions to the above, see below.
 *
 *  \subsection SSec_XPLAIN Atmel Xplain Board
 *  Ground the USB AVR JTAG's \c TCK pin to ground when powering on the board to start the bootloader. This assumes the
 *  \c HWBE fuse is cleared and the \c BOOTRST fuse is set as the HWBE pin is not user accessible on this board.
 *
 *  \subsection SSec_Leonardo Arduino Leonardo Board
 *  Ground \c IO13 when powering the board to start the bootloader. This assumes the \c HWBE fuse is cleared and the
 *  \c BOOTRST fuse is set as the HWBE pin is not user accessible on this board.
 *
 *  \section Sec_Installation Driver Installation
 *
 *  This bootloader uses the Generic Text-Only printer drivers inbuilt into all modern operating systems, thus no
 *  additional drivers need to be supplied for correct operation.
 *
 *  \section Sec_HostApp Host Controller Application
 *
 *  This bootloader is compatible with Notepad under Windows, and the command line \c lpr utility under Linux.
 *
 *  \subsection SSec_Notepad Notepad (Windows)
 *
 *  While most text applications under Windows will be compatible with the bootloader, the inbuilt Notepad utility
 *  is recommended as it will introduce minimal formatting changes to the output stream. To program with Notepad,
 *  open the target HEX file and print it to the Generic Text Only printer device the bootloader creates.
 *
 *  \subsection SSec_LPR LPR (Linux)
 *
 *  While the CUPS framework under Linux will enumerate the bootloader as a Generic Text-Only printer, many
 *  applications will refuse to print to the device due to the lack of rich formatting options available. As a result,
 *  under Linux HEX files must be printed via the low level \c lpr utility instead.
 *
 *  \code
 *  cat Mouse.hex | lpr
 *  \endcode
 *
 *  \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_PRINTER_SIGNATURE       0xDF20
 *
 *  #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_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.
 *
 *  \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, 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.
 *
 *  \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.
 *
 *  <table>
 *   <tr>
 *    <td>
 *     None
 *    </td>
 *   </tr>
 *  </table>
 */