1 .. SPDX-License-Identifier: GPL-2.0 OR GFDL-1. 1 .. SPDX-License-Identifier: GPL-2.0 OR GFDL-1.1-no-invariants-or-later
2 2
3 .. _Remote_controllers_Protocols: 3 .. _Remote_controllers_Protocols:
4 4
5 ***************************************** 5 *****************************************
6 Remote Controller Protocols and Scancodes 6 Remote Controller Protocols and Scancodes
7 ***************************************** 7 *****************************************
8 8
9 IR is encoded as a series of pulses and spaces 9 IR is encoded as a series of pulses and spaces, using a protocol. These
10 protocols can encode e.g. an address (which de 10 protocols can encode e.g. an address (which device should respond) and a
11 command: what it should do. The values for the 11 command: what it should do. The values for these are not always consistent
12 across different devices for a given protocol. 12 across different devices for a given protocol.
13 13
14 Therefore out the output of the IR decoder is 14 Therefore out the output of the IR decoder is a scancode; a single u32
15 value. Using keymap tables this can be mapped 15 value. Using keymap tables this can be mapped to linux key codes.
16 16
17 Other things can be encoded too. Some IR proto 17 Other things can be encoded too. Some IR protocols encode a toggle bit; this
18 is to distinguish whether the same button is b 18 is to distinguish whether the same button is being held down, or has been
19 released and pressed again. If has been releas 19 released and pressed again. If has been released and pressed again, the
20 toggle bit will invert from one IR message to 20 toggle bit will invert from one IR message to the next.
21 21
22 Some remotes have a pointer-type device which 22 Some remotes have a pointer-type device which can used to control the
23 mouse; some air conditioning systems can have 23 mouse; some air conditioning systems can have their target temperature
24 target set in IR. 24 target set in IR.
25 25
26 The following are the protocols the kernel kno 26 The following are the protocols the kernel knows about and also lists
27 how scancodes are encoded for each protocol. 27 how scancodes are encoded for each protocol.
28 28
29 rc-5 (RC_PROTO_RC5) 29 rc-5 (RC_PROTO_RC5)
30 ------------------- 30 -------------------
31 31
32 This IR protocol uses manchester encoding to e 32 This IR protocol uses manchester encoding to encode 14 bits. There is a
33 detailed description here https://www.sbprojec 33 detailed description here https://www.sbprojects.net/knowledge/ir/rc5.php.
34 34
35 The scancode encoding is *not* consistent with 35 The scancode encoding is *not* consistent with the lirc daemon (lircd) rc5
36 protocol, or the manchester BPF decoder. 36 protocol, or the manchester BPF decoder.
37 37
38 .. flat-table:: rc5 bits scancode mapping 38 .. flat-table:: rc5 bits scancode mapping
39 :widths: 1 1 2 39 :widths: 1 1 2
40 40
41 * - rc-5 bit 41 * - rc-5 bit
42 42
43 - scancode bit 43 - scancode bit
44 44
45 - description 45 - description
46 46
47 * - 1 47 * - 1
48 48
49 - none 49 - none
50 50
51 - Start bit, always set 51 - Start bit, always set
52 52
53 * - 1 53 * - 1
54 54
55 - 6 (inverted) 55 - 6 (inverted)
56 56
57 - 2nd start bit in rc5, re-used as 6th c 57 - 2nd start bit in rc5, re-used as 6th command bit
58 58
59 * - 1 59 * - 1
60 60
61 - none 61 - none
62 62
63 - Toggle bit 63 - Toggle bit
64 64
65 * - 5 65 * - 5
66 66
67 - 8 to 13 67 - 8 to 13
68 68
69 - Address 69 - Address
70 70
71 * - 6 71 * - 6
72 72
73 - 0 to 5 73 - 0 to 5
74 74
75 - Command 75 - Command
76 76
77 There is a variant of rc5 called either rc5x o 77 There is a variant of rc5 called either rc5x or extended rc5
78 where there the second stop bit is the 6th com 78 where there the second stop bit is the 6th command bit, but inverted.
79 This is done so it the scancodes and encoding 79 This is done so it the scancodes and encoding is compatible with existing
80 schemes. This bit is stored in bit 6 of the sc 80 schemes. This bit is stored in bit 6 of the scancode, inverted. This is
81 done to keep it compatible with plain rc-5 whe 81 done to keep it compatible with plain rc-5 where there are two start bits.
82 82
83 rc-5-sz (RC_PROTO_RC5_SZ) 83 rc-5-sz (RC_PROTO_RC5_SZ)
84 ------------------------- 84 -------------------------
85 This is much like rc-5 but one bit longer. The 85 This is much like rc-5 but one bit longer. The scancode is encoded
86 differently. 86 differently.
87 87
88 .. flat-table:: rc-5-sz bits scancode mapping 88 .. flat-table:: rc-5-sz bits scancode mapping
89 :widths: 1 1 2 89 :widths: 1 1 2
90 90
91 * - rc-5-sz bits 91 * - rc-5-sz bits
92 92
93 - scancode bit 93 - scancode bit
94 94
95 - description 95 - description
96 96
97 * - 1 97 * - 1
98 98
99 - none 99 - none
100 100
101 - Start bit, always set 101 - Start bit, always set
102 102
103 * - 1 103 * - 1
104 104
105 - 13 105 - 13
106 106
107 - Address bit 107 - Address bit
108 108
109 * - 1 109 * - 1
110 110
111 - none 111 - none
112 112
113 - Toggle bit 113 - Toggle bit
114 114
115 * - 6 115 * - 6
116 116
117 - 6 to 11 117 - 6 to 11
118 118
119 - Address 119 - Address
120 120
121 * - 6 121 * - 6
122 122
123 - 0 to 5 123 - 0 to 5
124 124
125 - Command 125 - Command
126 126
127 rc-5x-20 (RC_PROTO_RC5X_20) 127 rc-5x-20 (RC_PROTO_RC5X_20)
128 --------------------------- 128 ---------------------------
129 129
130 This rc-5 extended to encoded 20 bits. The is 130 This rc-5 extended to encoded 20 bits. The is a 3555 microseconds space
131 after the 8th bit. 131 after the 8th bit.
132 132
133 .. flat-table:: rc-5x-20 bits scancode mapping 133 .. flat-table:: rc-5x-20 bits scancode mapping
134 :widths: 1 1 2 134 :widths: 1 1 2
135 135
136 * - rc-5-sz bits 136 * - rc-5-sz bits
137 137
138 - scancode bit 138 - scancode bit
139 139
140 - description 140 - description
141 141
142 * - 1 142 * - 1
143 143
144 - none 144 - none
145 145
146 - Start bit, always set 146 - Start bit, always set
147 147
148 * - 1 148 * - 1
149 149
150 - 14 150 - 14
151 151
152 - Address bit 152 - Address bit
153 153
154 * - 1 154 * - 1
155 155
156 - none 156 - none
157 157
158 - Toggle bit 158 - Toggle bit
159 159
160 * - 5 160 * - 5
161 161
162 - 16 to 20 162 - 16 to 20
163 163
164 - Address 164 - Address
165 165
166 * - 6 166 * - 6
167 167
168 - 8 to 13 168 - 8 to 13
169 169
170 - Address 170 - Address
171 171
172 * - 6 172 * - 6
173 173
174 - 0 to 5 174 - 0 to 5
175 175
176 - Command 176 - Command
177 177
178 178
179 jvc (RC_PROTO_JVC) 179 jvc (RC_PROTO_JVC)
180 ------------------ 180 ------------------
181 181
182 The jvc protocol is much like nec, without the 182 The jvc protocol is much like nec, without the inverted values. It is
183 described here https://www.sbprojects.net/know 183 described here https://www.sbprojects.net/knowledge/ir/jvc.php.
184 184
185 The scancode is a 16 bits value, where the add 185 The scancode is a 16 bits value, where the address is the lower 8 bits
186 and the command the higher 8 bits; this is rev 186 and the command the higher 8 bits; this is reversed from IR order.
187 187
188 sony-12 (RC_PROTO_SONY12) 188 sony-12 (RC_PROTO_SONY12)
189 ------------------------- 189 -------------------------
190 190
191 The sony protocol is a pulse-width encoding. T 191 The sony protocol is a pulse-width encoding. There are three variants,
192 which just differ in number of bits and scanco 192 which just differ in number of bits and scancode encoding.
193 193
194 .. flat-table:: sony-12 bits scancode mapping 194 .. flat-table:: sony-12 bits scancode mapping
195 :widths: 1 1 2 195 :widths: 1 1 2
196 196
197 * - sony-12 bits 197 * - sony-12 bits
198 198
199 - scancode bit 199 - scancode bit
200 200
201 - description 201 - description
202 202
203 * - 5 203 * - 5
204 204
205 - 16 to 20 205 - 16 to 20
206 206
207 - device 207 - device
208 208
209 * - 7 209 * - 7
210 210
211 - 0 to 6 211 - 0 to 6
212 212
213 - function 213 - function
214 214
215 sony-15 (RC_PROTO_SONY15) 215 sony-15 (RC_PROTO_SONY15)
216 ------------------------- 216 -------------------------
217 217
218 The sony protocol is a pulse-width encoding. T 218 The sony protocol is a pulse-width encoding. There are three variants,
219 which just differ in number of bits and scanco 219 which just differ in number of bits and scancode encoding.
220 220
221 .. flat-table:: sony-12 bits scancode mapping 221 .. flat-table:: sony-12 bits scancode mapping
222 :widths: 1 1 2 222 :widths: 1 1 2
223 223
224 * - sony-12 bits 224 * - sony-12 bits
225 225
226 - scancode bit 226 - scancode bit
227 227
228 - description 228 - description
229 229
230 * - 8 230 * - 8
231 231
232 - 16 to 23 232 - 16 to 23
233 233
234 - device 234 - device
235 235
236 * - 7 236 * - 7
237 237
238 - 0 to 6 238 - 0 to 6
239 239
240 - function 240 - function
241 241
242 sony-20 (RC_PROTO_SONY20) 242 sony-20 (RC_PROTO_SONY20)
243 ------------------------- 243 -------------------------
244 244
245 The sony protocol is a pulse-width encoding. T 245 The sony protocol is a pulse-width encoding. There are three variants,
246 which just differ in number of bits and scanco 246 which just differ in number of bits and scancode encoding.
247 247
248 .. flat-table:: sony-20 bits scancode mapping 248 .. flat-table:: sony-20 bits scancode mapping
249 :widths: 1 1 2 249 :widths: 1 1 2
250 250
251 * - sony-20 bits 251 * - sony-20 bits
252 252
253 - scancode bit 253 - scancode bit
254 254
255 - description 255 - description
256 256
257 * - 5 257 * - 5
258 258
259 - 16 to 20 259 - 16 to 20
260 260
261 - device 261 - device
262 262
263 * - 7 263 * - 7
264 264
265 - 0 to 7 265 - 0 to 7
266 266
267 - device 267 - device
268 268
269 * - 8 269 * - 8
270 270
271 - 8 to 15 271 - 8 to 15
272 272
273 - extended bits 273 - extended bits
274 274
275 nec (RC_PROTO_NEC) 275 nec (RC_PROTO_NEC)
276 ------------------ 276 ------------------
277 277
278 The nec protocol encodes an 8 bit address and 278 The nec protocol encodes an 8 bit address and an 8 bit command. It is
279 described here https://www.sbprojects.net/know 279 described here https://www.sbprojects.net/knowledge/ir/nec.php. Note
280 that the protocol sends least significant bit 280 that the protocol sends least significant bit first.
281 281
282 As a check, the nec protocol sends the address 282 As a check, the nec protocol sends the address and command twice; the
283 second time it is inverted. This is done for v 283 second time it is inverted. This is done for verification.
284 284
285 A plain nec IR message has 16 bits; the high 8 285 A plain nec IR message has 16 bits; the high 8 bits are the address
286 and the low 8 bits are the command. 286 and the low 8 bits are the command.
287 287
288 nec-x (RC_PROTO_NECX) 288 nec-x (RC_PROTO_NECX)
289 --------------------- 289 ---------------------
290 290
291 Extended nec has a 16 bit address and a 8 bit 291 Extended nec has a 16 bit address and a 8 bit command. This is encoded
292 as a 24 bit value as you would expect, with th 292 as a 24 bit value as you would expect, with the lower 8 bits the command
293 and the upper 16 bits the address. 293 and the upper 16 bits the address.
294 294
295 nec-32 (RC_PROTO_NEC32) 295 nec-32 (RC_PROTO_NEC32)
296 ----------------------- 296 -----------------------
297 297
298 nec-32 does not send an inverted address or an 298 nec-32 does not send an inverted address or an inverted command; the
299 entire message, all 32 bits, are used. 299 entire message, all 32 bits, are used.
300 300
301 For this to be decoded correctly, the second 8 301 For this to be decoded correctly, the second 8 bits must not be the
302 inverted value of the first, and also the last 302 inverted value of the first, and also the last 8 bits must not be the
303 inverted value of the third 8 bit value. 303 inverted value of the third 8 bit value.
304 304
305 The scancode has a somewhat unusual encoding. 305 The scancode has a somewhat unusual encoding.
306 306
307 .. flat-table:: nec-32 bits scancode mapping 307 .. flat-table:: nec-32 bits scancode mapping
308 308
309 * - nec-32 bits 309 * - nec-32 bits
310 310
311 - scancode bit 311 - scancode bit
312 312
313 * - First 8 bits 313 * - First 8 bits
314 314
315 - 16 to 23 315 - 16 to 23
316 316
317 * - Second 8 bits 317 * - Second 8 bits
318 318
319 - 24 to 31 319 - 24 to 31
320 320
321 * - Third 8 bits 321 * - Third 8 bits
322 322
323 - 0 to 7 323 - 0 to 7
324 324
325 * - Fourth 8 bits 325 * - Fourth 8 bits
326 326
327 - 8 to 15 327 - 8 to 15
328 328
329 sanyo (RC_PROTO_SANYO) 329 sanyo (RC_PROTO_SANYO)
330 ---------------------- 330 ----------------------
331 331
332 The sanyo protocol is like the nec protocol, b 332 The sanyo protocol is like the nec protocol, but with 13 bits address
333 rather than 8 bits. Both the address and the c 333 rather than 8 bits. Both the address and the command are followed by
334 their inverted versions, but these are not pre 334 their inverted versions, but these are not present in the scancodes.
335 335
336 Bis 8 to 20 of the scancode is the 13 bits add 336 Bis 8 to 20 of the scancode is the 13 bits address, and the lower 8
337 bits are the command. 337 bits are the command.
338 338
339 mcir2-kbd (RC_PROTO_MCIR2_KBD) 339 mcir2-kbd (RC_PROTO_MCIR2_KBD)
340 ------------------------------ 340 ------------------------------
341 341
342 This protocol is generated by the Microsoft MC 342 This protocol is generated by the Microsoft MCE keyboard for keyboard
343 events. Refer to the ir-mce_kbd-decoder.c to s 343 events. Refer to the ir-mce_kbd-decoder.c to see how it is encoded.
344 344
345 mcir2-mse (RC_PROTO_MCIR2_MSE) 345 mcir2-mse (RC_PROTO_MCIR2_MSE)
346 ------------------------------ 346 ------------------------------
347 347
348 This protocol is generated by the Microsoft MC 348 This protocol is generated by the Microsoft MCE keyboard for pointer
349 events. Refer to the ir-mce_kbd-decoder.c to s 349 events. Refer to the ir-mce_kbd-decoder.c to see how it is encoded.
350 350
351 rc-6-0 (RC_PROTO_RC6_0) 351 rc-6-0 (RC_PROTO_RC6_0)
352 ----------------------- 352 -----------------------
353 353
354 This is the rc-6 in mode 0. rc-6 is described 354 This is the rc-6 in mode 0. rc-6 is described here
355 https://www.sbprojects.net/knowledge/ir/rc6.ph 355 https://www.sbprojects.net/knowledge/ir/rc6.php.
356 The scancode is the exact 16 bits as in the pr 356 The scancode is the exact 16 bits as in the protocol. There is also a
357 toggle bit. 357 toggle bit.
358 358
359 rc-6-6a-20 (RC_PROTO_RC6_6A_20) 359 rc-6-6a-20 (RC_PROTO_RC6_6A_20)
360 ------------------------------- 360 -------------------------------
361 361
362 This is the rc-6 in mode 6a, 20 bits. rc-6 is 362 This is the rc-6 in mode 6a, 20 bits. rc-6 is described here
363 https://www.sbprojects.net/knowledge/ir/rc6.ph 363 https://www.sbprojects.net/knowledge/ir/rc6.php.
364 The scancode is the exact 20 bits 364 The scancode is the exact 20 bits
365 as in the protocol. There is also a toggle bit 365 as in the protocol. There is also a toggle bit.
366 366
367 rc-6-6a-24 (RC_PROTO_RC6_6A_24) 367 rc-6-6a-24 (RC_PROTO_RC6_6A_24)
368 ------------------------------- 368 -------------------------------
369 369
370 This is the rc-6 in mode 6a, 24 bits. rc-6 is 370 This is the rc-6 in mode 6a, 24 bits. rc-6 is described here
371 https://www.sbprojects.net/knowledge/ir/rc6.ph 371 https://www.sbprojects.net/knowledge/ir/rc6.php.
372 The scancode is the exact 24 bits 372 The scancode is the exact 24 bits
373 as in the protocol. There is also a toggle bit 373 as in the protocol. There is also a toggle bit.
374 374
375 rc-6-6a-32 (RC_PROTO_RC6_6A_32) 375 rc-6-6a-32 (RC_PROTO_RC6_6A_32)
376 ------------------------------- 376 -------------------------------
377 377
378 This is the rc-6 in mode 6a, 32 bits. rc-6 is 378 This is the rc-6 in mode 6a, 32 bits. rc-6 is described here
379 https://www.sbprojects.net/knowledge/ir/rc6.ph 379 https://www.sbprojects.net/knowledge/ir/rc6.php.
380 The upper 16 bits are the vendor, 380 The upper 16 bits are the vendor,
381 and the lower 16 bits are the vendor-specific 381 and the lower 16 bits are the vendor-specific bits. This protocol is
382 for the non-Microsoft MCE variant (vendor != 0 382 for the non-Microsoft MCE variant (vendor != 0x800f).
383 383
384 384
385 rc-6-mce (RC_PROTO_RC6_MCE) 385 rc-6-mce (RC_PROTO_RC6_MCE)
386 --------------------------- 386 ---------------------------
387 387
388 This is the rc-6 in mode 6a, 32 bits. The uppe 388 This is the rc-6 in mode 6a, 32 bits. The upper 16 bits are the vendor,
389 and the lower 16 bits are the vendor-specific 389 and the lower 16 bits are the vendor-specific bits. This protocol is
390 for the Microsoft MCE variant (vendor = 0x800f 390 for the Microsoft MCE variant (vendor = 0x800f). The toggle bit in the
391 protocol itself is ignored, and the 16th bit s 391 protocol itself is ignored, and the 16th bit should be takes as the toggle
392 bit. 392 bit.
393 393
394 sharp (RC_PROTO_SHARP) 394 sharp (RC_PROTO_SHARP)
395 ---------------------- 395 ----------------------
396 396
397 This is a protocol used by Sharp VCRs, is desc 397 This is a protocol used by Sharp VCRs, is described here
398 https://www.sbprojects.net/knowledge/ir/sharp. 398 https://www.sbprojects.net/knowledge/ir/sharp.php. There is a very long
399 (40ms) space between the normal and inverted v 399 (40ms) space between the normal and inverted values, and some IR receivers
400 cannot decode this. 400 cannot decode this.
401 401
402 There is a 5 bit address and a 8 bit command. 402 There is a 5 bit address and a 8 bit command. In the scancode the address is
403 in bits 8 to 12, and the command in bits 0 to 403 in bits 8 to 12, and the command in bits 0 to 7.
404 404
405 xmp (RC_PROTO_XMP) 405 xmp (RC_PROTO_XMP)
406 ------------------ 406 ------------------
407 407
408 This protocol has several versions and only ve 408 This protocol has several versions and only version 1 is supported. Refer
409 to the decoder (ir-xmp-decoder.c) to see how i 409 to the decoder (ir-xmp-decoder.c) to see how it is encoded.
410 410
411 411
412 cec (RC_PROTO_CEC) 412 cec (RC_PROTO_CEC)
413 ------------------ 413 ------------------
414 414
415 This is not an IR protocol, this is a protocol 415 This is not an IR protocol, this is a protocol over CEC. The CEC
416 infrastructure uses rc-core for handling CEC c 416 infrastructure uses rc-core for handling CEC commands, so that they
417 can easily be remapped. 417 can easily be remapped.
418 418
419 imon (RC_PROTO_IMON) 419 imon (RC_PROTO_IMON)
420 -------------------- 420 --------------------
421 421
422 This protocol is used by Antec Veris/SoundGrap 422 This protocol is used by Antec Veris/SoundGraph iMON remotes.
423 423
424 The protocol 424 The protocol
425 describes both button presses and pointer move 425 describes both button presses and pointer movements. The protocol encodes
426 31 bits, and the scancode is simply the 31 bit 426 31 bits, and the scancode is simply the 31 bits with the top bit always 0.
427 427
428 rc-mm-12 (RC_PROTO_RCMM12) 428 rc-mm-12 (RC_PROTO_RCMM12)
429 -------------------------- 429 --------------------------
430 430
431 The rc-mm protocol is described here 431 The rc-mm protocol is described here
432 https://www.sbprojects.net/knowledge/ir/rcmm.p 432 https://www.sbprojects.net/knowledge/ir/rcmm.php. The scancode is simply
433 the 12 bits. 433 the 12 bits.
434 434
435 rc-mm-24 (RC_PROTO_RCMM24) 435 rc-mm-24 (RC_PROTO_RCMM24)
436 -------------------------- 436 --------------------------
437 437
438 The rc-mm protocol is described here 438 The rc-mm protocol is described here
439 https://www.sbprojects.net/knowledge/ir/rcmm.p 439 https://www.sbprojects.net/knowledge/ir/rcmm.php. The scancode is simply
440 the 24 bits. 440 the 24 bits.
441 441
442 rc-mm-32 (RC_PROTO_RCMM32) 442 rc-mm-32 (RC_PROTO_RCMM32)
443 -------------------------- 443 --------------------------
444 444
445 The rc-mm protocol is described here 445 The rc-mm protocol is described here
446 https://www.sbprojects.net/knowledge/ir/rcmm.p 446 https://www.sbprojects.net/knowledge/ir/rcmm.php. The scancode is simply
447 the 32 bits. 447 the 32 bits.
448 448
449 xbox-dvd (RC_PROTO_XBOX_DVD) 449 xbox-dvd (RC_PROTO_XBOX_DVD)
450 ---------------------------- 450 ----------------------------
451 451
452 This protocol is used by XBox DVD Remote, whic 452 This protocol is used by XBox DVD Remote, which was made for the original
453 XBox. There is no in-kernel decoder or encoder 453 XBox. There is no in-kernel decoder or encoder for this protocol. The usb
454 device decodes the protocol. There is a BPF de 454 device decodes the protocol. There is a BPF decoder available in v4l-utils.
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