tmk_core/protocol/adb.c

   1 /*
   2 Copyright 2011 Jun WAKO <wakojun@gmail.com>
   3 Copyright 2013 Shay Green <gblargg@gmail.com>
   4
   5 This software is licensed with a Modified BSD License.
   6 All of this is supposed to be Free Software, Open Source, DFSG-free,
   7 GPL-compatible, and OK to use in both free and proprietary applications.
   8 Additions and corrections to this file are welcome.
   9
  10
  11 Redistribution and use in source and binary forms, with or without
  12 modification, are permitted provided that the following conditions are met:
  13
  14 * Redistributions of source code must retain the above copyright
  15   notice, this list of conditions and the following disclaimer.
  16
  17 * Redistributions in binary form must reproduce the above copyright
  18   notice, this list of conditions and the following disclaimer in
  19   the documentation and/or other materials provided with the
  20   distribution.
  21
  22 * Neither the name of the copyright holders nor the names of
  23   contributors may be used to endorse or promote products derived
  24   from this software without specific prior written permission.
  25
  26 THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
  27 AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  28 IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  29 ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
  30 LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  31 CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  32 SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  33 INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  34 CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  35 ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  36 POSSIBILITY OF SUCH DAMAGE.
  37 */
  38
  39 #include <stdbool.h>
  40 #include <util/delay.h>
  41 #include <avr/io.h>
  42 #include <avr/interrupt.h>
  43 #include "adb.h"
  44
  45
  46 // GCC doesn't inline functions normally
  47 #define data_lo() (ADB_DDR |=  (1<<ADB_DATA_BIT))
  48 #define data_hi() (ADB_DDR &= ~(1<<ADB_DATA_BIT))
  49 #define data_in() (ADB_PIN &   (1<<ADB_DATA_BIT))
  50
  51 #ifdef ADB_PSW_BIT
  52 static inline void psw_lo(void);
  53 static inline void psw_hi(void);
  54 static inline bool psw_in(void);
  55 #endif
  56
  57 static inline void attention(void);
  58 static inline void place_bit0(void);
  59 static inline void place_bit1(void);
  60 static inline void send_byte(uint8_t data);
  61 static inline uint16_t wait_data_lo(uint16_t us);
  62 static inline uint16_t wait_data_hi(uint16_t us);
  63
  64
  65 void adb_host_init(void)
  66 {
  67     ADB_PORT &= ~(1<<ADB_DATA_BIT);
  68     data_hi();
  69 #ifdef ADB_PSW_BIT
  70     psw_hi();
  71 #endif
  72 }
  73
  74 #ifdef ADB_PSW_BIT
  75 bool adb_host_psw(void)
  76 {
  77     return psw_in();
  78 }
  79 #endif
  80
  81 /*
  82  * Don't call this in a row without the delay, otherwise it makes some of poor controllers
  83  * overloaded and misses strokes. Recommended interval is 12ms.
  84  *
  85  * Thanks a lot, blargg!
  86  * <http://geekhack.org/index.php?topic=14290.msg1068919#msg1068919>
  87  * <http://geekhack.org/index.php?topic=14290.msg1070139#msg1070139>
  88  */
  89 uint16_t adb_host_kbd_recv(uint8_t addr)
  90 {
  91     return adb_host_talk(addr, ADB_REG_0);
  92 }
  93
  94 #ifdef ADB_MOUSE_ENABLE
  95 void adb_mouse_init(void) {
  96             return;
  97 }
  98
  99 uint16_t adb_host_mouse_recv(void)
 100 {
 101     return adb_host_talk(ADB_ADDR_MOUSE, ADB_REG_0);
 102 }
 103 #endif
 104
 105 uint16_t adb_host_talk(uint8_t addr, uint8_t reg)
 106 {
 107     uint16_t data = 0;
 108     cli();
 109     attention();
 110     send_byte((addr<<4) | (ADB_CMD_TALK<<2) | reg);
 111     place_bit0();               // Stopbit(0)
 112     if (!wait_data_hi(500)) {    // Service Request(310us Adjustable Keyboard): just ignored
 113         sei();
 114         return -30;             // something wrong
 115     }
 116     if (!wait_data_lo(500)) {   // Tlt/Stop to Start(140-260us)
 117         sei();
 118         return 0;               // No data to send
 119     }
 120
 121     uint8_t n = 17; // start bit + 16 data bits
 122     do {
 123         uint8_t lo = (uint8_t) wait_data_hi(130);
 124         if (!lo)
 125             goto error;
 126
 127         uint8_t hi = (uint8_t) wait_data_lo(lo);
 128         if (!hi)
 129             goto error;
 130
 131         hi = lo - hi;
 132         lo = 130 - lo;
 133
 134         data <<= 1;
 135         if (lo < hi) {
 136             data |= 1;
 137         }
 138         else if (n == 17) {
 139             sei();
 140             return -20;
 141         }
 142     }
 143     while ( --n );
 144
 145     // Stop bit can't be checked normally since it could have service request lenghtening
 146     // and its high state never goes low.
 147     if (!wait_data_hi(351) || wait_data_lo(91)) {
 148         sei();
 149         return -21;
 150     }
 151     sei();
 152     return data;
 153
 154 error:
 155     sei();
 156     return -n;
 157 }
 158
 159 void adb_host_listen(uint8_t addr, uint8_t reg, uint8_t data_h, uint8_t data_l)
 160 {
 161     cli();
 162     attention();
 163     send_byte((addr<<4) | (ADB_CMD_LISTEN<<2) | reg);
 164     place_bit0();               // Stopbit(0)
 165     _delay_us(200);             // Tlt/Stop to Start
 166     place_bit1();               // Startbit(1)
 167     send_byte(data_h);
 168     send_byte(data_l);
 169     place_bit0();               // Stopbit(0);
 170     sei();
 171 }
 172
 173 // send state of LEDs
 174 void adb_host_kbd_led(uint8_t addr, uint8_t led)
 175 {
 176     // Listen Register2
 177     //  upper byte: not used
 178     //  lower byte: bit2=ScrollLock, bit1=CapsLock, bit0=NumLock
 179     adb_host_listen(addr, 2, 0, led & 0x07);
 180 }
 181
 182
 183 #ifdef ADB_PSW_BIT
 184 static inline void psw_lo()
 185 {
 186     ADB_DDR  |=  (1<<ADB_PSW_BIT);
 187     ADB_PORT &= ~(1<<ADB_PSW_BIT);
 188 }
 189 static inline void psw_hi()
 190 {
 191     ADB_PORT |=  (1<<ADB_PSW_BIT);
 192     ADB_DDR  &= ~(1<<ADB_PSW_BIT);
 193 }
 194 static inline bool psw_in()
 195 {
 196     ADB_PORT |=  (1<<ADB_PSW_BIT);
 197     ADB_DDR  &= ~(1<<ADB_PSW_BIT);
 198     return ADB_PIN&(1<<ADB_PSW_BIT);
 199 }
 200 #endif
 201
 202 static inline void attention(void)
 203 {
 204     data_lo();
 205     _delay_us(800-35); // bit1 holds lo for 35 more
 206     place_bit1();
 207 }
 208
 209 static inline void place_bit0(void)
 210 {
 211     data_lo();
 212     _delay_us(65);
 213     data_hi();
 214     _delay_us(35);
 215 }
 216
 217 static inline void place_bit1(void)
 218 {
 219     data_lo();
 220     _delay_us(35);
 221     data_hi();
 222     _delay_us(65);
 223 }
 224
 225 static inline void send_byte(uint8_t data)
 226 {
 227     for (int i = 0; i < 8; i++) {
 228         if (data&(0x80>>i))
 229             place_bit1();
 230         else
 231             place_bit0();
 232     }
 233 }
 234
 235 // These are carefully coded to take 6 cycles of overhead.
 236 // inline asm approach became too convoluted
 237 static inline uint16_t wait_data_lo(uint16_t us)
 238 {
 239     do {
 240         if ( !data_in() )
 241             break;
 242         _delay_us(1 - (6 * 1000000.0 / F_CPU));
 243     }
 244     while ( --us );
 245     return us;
 246 }
 247
 248 static inline uint16_t wait_data_hi(uint16_t us)
 249 {
 250     do {
 251         if ( data_in() )
 252             break;
 253         _delay_us(1 - (6 * 1000000.0 / F_CPU));
 254     }
 255     while ( --us );
 256     return us;
 257 }
 258
 259
 260 /*
 261 ADB Protocol
 262 ============
 263
 264 Resources
 265 ---------
 266 ADB - The Untold Story: Space Aliens Ate My Mouse
 267     http://developer.apple.com/legacy/mac/library/#technotes/hw/hw_01.html
 268 ADB Manager
 269     http://developer.apple.com/legacy/mac/library/documentation/mac/pdf/Devices/ADB_Manager.pdf
 270     Service request(5-17)
 271 Apple IIgs Hardware Reference Second Edition [Chapter6 p121]
 272     ftp://ftp.apple.asimov.net/pub/apple_II/documentation/Apple%20IIgs%20Hardware%20Reference.pdf
 273 ADB Keycode
 274     http://72.0.193.250/Documentation/macppc/adbkeycodes/
 275     http://m0115.web.fc2.com/m0115.jpg
 276     [Inside Macintosh volume V, pages 191-192]
 277     http://www.opensource.apple.com/source/IOHIDFamily/IOHIDFamily-421.18.3/IOHIDFamily/Cosmo_USB2ADB.c
 278 ADB Signaling
 279     http://kbdbabel.sourceforge.net/doc/kbd_signaling_pcxt_ps2_adb.pdf
 280 ADB Overview & History
 281     http://en.wikipedia.org/wiki/Apple_Desktop_Bus
 282 Microchip Application Note: ADB device(with code for PIC16C)
 283     http://www.microchip.com/stellent/idcplg?IdcService=SS_GET_PAGE&nodeId=1824&appnote=en011062
 284 AVR ATtiny2131 ADB to PS/2 converter(Japanese)
 285     http://hp.vector.co.jp/authors/VA000177/html/KeyBoardA5DEA5CBA5A2II.html
 286
 287
 288 Pinouts
 289 -------
 290     ADB female socket from the front:
 291     __________
 292     |        | <--- top
 293     | 4o  o3 |
 294     |2o    o1|
 295     |   ==   |
 296     |________| <--- bottom
 297       |    |   <--- 4pins
 298
 299
 300     ADB female socket from bottom:
 301
 302     ========== <--- front
 303     |        |
 304     |        |
 305     |2o    o1|
 306     |4o    o3|
 307     ---------- <--- back
 308
 309     1: Data
 310     2: Power SW(low when press Power key)
 311     3: Vcc(5V)
 312     4: GND
 313
 314
 315 Commands
 316 --------
 317     ADB command is 1byte and consists of 4bit-address, 2bit-command
 318     type and 2bit-register. The commands are always sent by Host.
 319
 320     Command format:
 321     7 6 5 4 3 2 1 0
 322     | | | |------------ address
 323             | |-------- command type
 324                 | |---- register
 325
 326     bits                commands
 327     ------------------------------------------------------
 328     - - - - 0 0 0 0     Send Reset(reset all devices)
 329     A A A A 0 0 0 1     Flush(reset a device)
 330     - - - - 0 0 1 0     Reserved
 331     - - - - 0 0 1 1     Reserved
 332     - - - - 0 1 - -     Reserved
 333     A A A A 1 0 R R     Listen(write to a device)
 334     A A A A 1 1 R R     Talk(read from a device)
 335
 336     The command to read keycodes from keyboard is 0x2C which
 337     consist of keyboard address 2 and Talk against register 0.
 338
 339     Address:
 340     2:  keyboard
 341     3:  mice
 342
 343     Registers:
 344     0: application(keyboard uses this to store its data.)
 345     1: application
 346     2: application(keyboard uses this for LEDs and state of modifiers)
 347     3: status and command
 348
 349
 350 Communication
 351 -------------
 352     This is a minimum information for keyboard communication.
 353     See "Resources" for detail.
 354
 355     Signaling:
 356
 357     ~~~~____________~~||||||||||||__~~~~~_~~|||||||||||||||__~~~~
 358
 359         |800us     |  |7 Command 0|  |   |  |15-64  Data  0|Stopbit(0)
 360         +Attention |              |  |   +Startbit(1)
 361                    +Startbit(1)   |  +Tlt(140-260us)
 362                                   +stopbit(0)
 363
 364     Bit cells:
 365
 366     bit0: ______~~~
 367           65    :35us
 368
 369     bit1: ___~~~~~~
 370           35 :65us
 371
 372     bit0 low time: 60-70% of bit cell(42-91us)
 373     bit1 low time: 30-40% of bit cell(21-52us)
 374     bit cell time: 70-130us
 375     [from Apple IIgs Hardware Reference Second Edition]
 376
 377     Criterion for bit0/1:
 378     After 55us if line is low/high then bit is 0/1.
 379
 380     Attention & start bit:
 381     Host asserts low in 560-1040us then places start bit(1).
 382
 383     Tlt(Stop to Start):
 384     Bus stays high in 140-260us then device places start bit(1).
 385
 386     Global reset:
 387     Host asserts low in 2.8-5.2ms. All devices are forced to reset.
 388
 389     Service request from device(Srq):
 390     Device can request to send at commad(Global only?) stop bit.
 391     Requesting device keeps low for 140-260us at stop bit of command.
 392
 393
 394 Keyboard Data(Register0)
 395     This 16bit data can contains two keycodes and two released flags.
 396     First keycode is palced in upper byte. When one keyocode is sent,
 397     lower byte is 0xFF.
 398     Release flag is 1 when key is released.
 399
 400     1514 . . . . . 8 7 6 . . . . . 0
 401      | | | | | | | | | +-+-+-+-+-+-+-   Keycode2
 402      | | | | | | | | +---------------   Released2(1 when the key is released)
 403      | +-+-+-+-+-+-+-----------------   Keycode1
 404      +-------------------------------   Released1(1 when the key is released)
 405
 406     Keycodes:
 407     Scancode consists of 7bit keycode and 1bit release flag.
 408     Device can send two keycodes at once. If just one keycode is sent
 409     keycode1 contains it and keyocode2 is 0xFF.
 410
 411     Power switch:
 412     You can read the state from PSW line(active low) however
 413     the switch has a special scancode 0x7F7F, so you can
 414     also read from Data line. It uses 0xFFFF for release scancode.
 415
 416 Keyboard LEDs & state of keys(Register2)
 417     This register hold current state of three LEDs and nine keys.
 418     The state of LEDs can be changed by sending Listen command.
 419
 420     1514 . . . . . . 7 6 5 . 3 2 1 0
 421      | | | | | | | | | | | | | | | +-   LED1(NumLock)
 422      | | | | | | | | | | | | | | +---   LED2(CapsLock)
 423      | | | | | | | | | | | | | +-----   LED3(ScrollLock)
 424      | | | | | | | | | | +-+-+-------   Reserved
 425      | | | | | | | | | +-------------   ScrollLock
 426      | | | | | | | | +---------------   NumLock
 427      | | | | | | | +-----------------   Apple/Command
 428      | | | | | | +-------------------   Option
 429      | | | | | +---------------------   Shift
 430      | | | | +-----------------------   Control
 431      | | | +-------------------------   Reset/Power
 432      | | +---------------------------   CapsLock
 433      | +-----------------------------   Delete
 434      +-------------------------------   Reserved
 435
 436 Address, Handler ID and bits(Register3)
 437     1514131211 . . 8 7 . . . . . . 0
 438      | | | | | | | | | | | | | | | |
 439      | | | | | | | | +-+-+-+-+-+-+-+-   Handler ID
 440      | | | | +-+-+-+-----------------   Address
 441      | | | +-------------------------   0
 442      | | +---------------------------   Service request enable(1 = enabled)
 443      | +-----------------------------   Exceptional event(alwyas 1 if not used)
 444      +-------------------------------   0
 445
 446 ADB Bit Cells
 447     bit cell time: 70-130us
 448     low part of bit0: 60-70% of bit cell
 449     low part of bit1: 30-40% of bit cell
 450
 451        bit cell time         70us        130us
 452        --------------------------------------------
 453        low  part of bit0     42-49       78-91
 454        high part of bit0     21-28       39-52
 455        low  part of bit1     21-28       39-52
 456        high part of bit1     42-49       78-91
 457
 458
 459     bit0:
 460        70us bit cell:
 461          ____________~~~~~~
 462          42-49        21-28
 463
 464        130us bit cell:
 465          ____________~~~~~~
 466          78-91        39-52
 467
 468     bit1:
 469        70us bit cell:
 470          ______~~~~~~~~~~~~
 471          21-28        42-49
 472
 473        130us bit cell:
 474          ______~~~~~~~~~~~~
 475          39-52        78-91
 476
 477     [from Apple IIgs Hardware Reference Second Edition]
 478
 479 Keyboard Handle ID
 480     Apple Standard Keyboard M0116:      0x01
 481     Apple Extended Keyboard M0115:      0x02
 482     Apple Extended Keyboard II M3501:   0x02
 483     Apple Adjustable Keybaord:          0x10
 484
 485     http://lxr.free-electrons.com/source/drivers/macintosh/adbhid.c?v=4.4#L802
 486
 487 END_OF_ADB
 488 */