Mercurial > ~darius > hgwebdir.cgi > avr-lib
annotate ds1307.c @ 3:15d89caaf516
Add support for single UART devices, although untested apart from a compile.
Doesn't break dual UART ones :)
Also checks for PRR before setting it.
author | darius@Inchoate |
---|---|
date | Wed, 11 Mar 2009 17:28:39 +1030 |
parents | 3879f487b661 |
children | 3da232f97e81 |
rev | line source |
---|---|
0 | 1 /* |
2 * Interface to a DS1307 | |
3 * | |
4 * Copyright (c) 2008 | |
5 * Daniel O'Connor <darius@dons.net.au>. All rights reserved. | |
6 * | |
7 * Redistribution and use in source and binary forms, with or without | |
8 * modification, are permitted provided that the following conditions | |
9 * are met: | |
10 * 1. Redistributions of source code must retain the above copyright | |
11 * notice, this list of conditions and the following disclaimer. | |
12 * 2. Redistributions in binary form must reproduce the above copyright | |
13 * notice, this list of conditions and the following disclaimer in the | |
14 * documentation and/or other materials provided with the distribution. | |
15 * | |
16 * THIS SOFTWARE IS PROVIDED BY AUTHOR AND CONTRIBUTORS ``AS IS'' AND | |
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE | |
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE | |
19 * ARE DISCLAIMED. IN NO EVENT SHALL AUTHOR OR CONTRIBUTORS BE LIABLE | |
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL | |
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS | |
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) | |
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT | |
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY | |
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF | |
26 * SUCH DAMAGE. | |
27 */ | |
28 | |
29 #include <stdio.h> | |
30 #include <stdlib.h> | |
31 #include <inttypes.h> | |
32 #include <avr/io.h> | |
33 #include <avr/pgmspace.h> | |
34 #include <util/twi.h> | |
35 #include <util/delay.h> | |
36 | |
37 #include "ds1307.h" | |
38 | |
39 // #define TWDEBUG | |
40 | |
41 /* | |
42 * ds1307_init | |
43 * | |
44 * Setup TWI interface | |
45 * | |
46 */ | |
47 int | |
48 ds1307_init(void) { | |
3
15d89caaf516
Add support for single UART devices, although untested apart from a compile.
darius@Inchoate
parents:
0
diff
changeset
|
49 #ifdef PRR |
0 | 50 PRR &= _BV(PRTWI); /* Power TWI on - note that the |
51 * datasheet says this is already 0 at | |
52 * power on.. */ | |
3
15d89caaf516
Add support for single UART devices, although untested apart from a compile.
darius@Inchoate
parents:
0
diff
changeset
|
53 #endif |
0 | 54 TWSR = 0; /* TWI Prescaler = 1 */ |
55 #if F_CPU < 3600000UL | |
56 TWBR = 10; /* Smallest valid TWBR */ | |
57 #else | |
58 TWBR = (F_CPU / 100000UL - 16) / 2; | |
59 #endif | |
60 | |
61 TWCR = _BV(TWEN); | |
62 | |
63 return(0); | |
64 } | |
65 | |
66 /* | |
67 * iic_read | |
68 * | |
69 * Read len bytes of data from address adr in slave sla into | |
70 * data. Presume that the slave auto-increments the address on | |
71 * successive reads. | |
72 * | |
73 * Returns the number of bytes read, or the following on failure. | |
74 * IIC_STFAIL Could generate START condition (broken bus or busy). | |
75 * IIC_FAILARB Failed bus arbitration. | |
76 * IIC_SLNAK Slave NAK'd. | |
77 * IIC_NOREPLY No reply (no such slave?) | |
78 * IIC_UNKNOWN Unexpected return from TWI reg. | |
79 * | |
80 * Heaviy cribbed from twitest.c by Joerg Wunsch | |
81 */ | |
82 int8_t | |
83 iic_read(uint8_t *data, uint8_t len, uint8_t adr, uint8_t sla) { | |
84 uint8_t twst, twcr, cnt; | |
85 | |
86 /* Generate START */ | |
87 TWCR = _BV(TWINT) | _BV(TWSTA) | _BV(TWEN); | |
88 | |
89 /* Spin waiting for START to be generated */ | |
90 while ((TWCR & _BV(TWINT)) == 0) | |
91 ; | |
92 switch (twst = TW_STATUS) { | |
93 case TW_REP_START: /* OK but shouldn't happen */ | |
94 case TW_START: | |
95 break; | |
96 | |
97 case TW_MT_ARB_LOST: | |
98 return IIC_FAILARB; | |
99 break; | |
100 | |
101 default: | |
102 /* Not in start condition, bail */ | |
103 return IIC_UNKNOWN; | |
104 } | |
105 #ifdef TWDEBUG | |
106 printf_P(PSTR("Sent START\r\n")); | |
107 #endif | |
108 /* Send SLA+W */ | |
109 TWDR = sla | TW_WRITE; | |
110 TWCR = _BV(TWINT) | _BV(TWEN); | |
111 | |
112 /* Spin waiting for a response to be generated */ | |
113 while ((TWCR & _BV(TWINT)) == 0) | |
114 ; | |
115 | |
116 #ifdef TWDEBUG | |
117 printf_P(PSTR("Sent SLA+W\r\n")); | |
118 #endif | |
119 switch (twst = TW_STATUS) { | |
120 case TW_MT_SLA_ACK: | |
121 break; | |
122 | |
123 case TW_MT_SLA_NACK: | |
124 /* Send STOP */ | |
125 TWCR = _BV(TWINT) | _BV(TWSTO) | _BV(TWEN); | |
126 return IIC_SLNAK; | |
127 | |
128 case TW_MT_ARB_LOST: | |
129 return IIC_FAILARB; | |
130 break; | |
131 | |
132 default: | |
133 /* Send STOP */ | |
134 TWCR = _BV(TWINT) | _BV(TWSTO) | _BV(TWEN); | |
135 return IIC_UNKNOWN; | |
136 } | |
137 /* Send address */ | |
138 TWDR = adr; | |
139 TWCR = _BV(TWINT) | _BV(TWEN); | |
140 | |
141 /* Spin waiting for a response to be generated */ | |
142 while ((TWCR & _BV(TWINT)) == 0) | |
143 ; | |
144 #ifdef TWDEBUG | |
145 printf_P(PSTR("Sent address\r\n")); | |
146 #endif | |
147 switch ((twst = TW_STATUS)) { | |
148 case TW_MT_DATA_ACK: | |
149 break; | |
150 | |
151 case TW_MT_DATA_NACK: | |
152 /* Send STOP */ | |
153 TWCR = _BV(TWINT) | _BV(TWSTO) | _BV(TWEN); | |
154 return IIC_SLNAK; | |
155 | |
156 case TW_MT_ARB_LOST: | |
157 return IIC_FAILARB; | |
158 | |
159 default: | |
160 /* Send STOP */ | |
161 TWCR = _BV(TWINT) | _BV(TWSTO) | _BV(TWEN); | |
162 return IIC_UNKNOWN; | |
163 } | |
164 | |
165 /* Master receive cycle */ | |
166 TWCR = _BV(TWINT) | _BV(TWSTA) | _BV(TWEN); | |
167 while ((TWCR & _BV(TWINT)) == 0) /* wait for transmission */ | |
168 ; | |
169 | |
170 #ifdef TWDEBUG | |
171 printf_P(PSTR("Sent START\r\n")); | |
172 #endif | |
173 switch ((twst = TW_STATUS)) { | |
174 case TW_REP_START: /* OK but shouldn't happen */ | |
175 case TW_START: | |
176 break; | |
177 | |
178 case TW_MT_ARB_LOST: | |
179 return IIC_FAILARB; | |
180 | |
181 default: | |
182 /* Send STOP */ | |
183 TWCR = _BV(TWINT) | _BV(TWSTO) | _BV(TWEN); | |
184 return IIC_UNKNOWN; | |
185 } | |
186 | |
187 /* send SLA+R */ | |
188 TWDR = sla | TW_READ; | |
189 TWCR = _BV(TWINT) | _BV(TWEN); /* clear interrupt to start transmission */ | |
190 | |
191 /* Spin waiting for a response to be generated */ | |
192 while ((TWCR & _BV(TWINT)) == 0) | |
193 ; | |
194 #ifdef TWDEBUG | |
195 printf_P(PSTR("Sent SLA+R\r\n")); | |
196 #endif | |
197 switch ((twst = TW_STATUS)) { | |
198 case TW_MR_SLA_ACK: | |
199 break; | |
200 | |
201 case TW_MR_SLA_NACK: | |
202 /* Send STOP */ | |
203 TWCR = _BV(TWINT) | _BV(TWSTO) | _BV(TWEN); | |
204 return IIC_SLNAK; | |
205 | |
206 case TW_MR_ARB_LOST: | |
207 return IIC_FAILARB; | |
208 | |
209 default: | |
210 /* Send STOP */ | |
211 TWCR = _BV(TWINT) | _BV(TWSTO) | _BV(TWEN); | |
212 return IIC_UNKNOWN; | |
213 } | |
214 | |
215 cnt = 0; | |
216 for (twcr = _BV(TWINT) | _BV(TWEN) | _BV(TWEA); | |
217 len > 0; len--) { | |
218 /* Send NAK on last byte */ | |
219 if (len == 1) | |
220 twcr = _BV(TWINT) | _BV(TWEN); | |
221 TWCR = twcr; /* clear int to start transmission */ | |
222 /* Spin waiting for a response to be generated */ | |
223 while ((TWCR & _BV(TWINT)) == 0) | |
224 ; | |
225 #ifdef TWDEBUG | |
226 printf_P(PSTR("Data request done\r\n")); | |
227 #endif | |
228 switch ((twst = TW_STATUS)) { | |
229 case TW_MR_DATA_NACK: | |
230 /* Send STOP */ | |
231 TWCR = _BV(TWINT) | _BV(TWSTO) | _BV(TWEN); | |
232 //printf_P(PSTR("NACK on byte %d\r\n"), cnt); | |
233 return cnt; | |
234 | |
235 case TW_MR_DATA_ACK: | |
236 *data++ = TWDR; | |
237 //printf_P(PSTR("ACK on byte %d for 0x%02x\r\n"), cnt, *(data - 1)); | |
238 cnt++; | |
239 break; | |
240 | |
241 default: | |
242 return IIC_UNKNOWN; | |
243 } | |
244 } | |
245 | |
246 /* Send STOP */ | |
247 TWCR = _BV(TWINT) | _BV(TWSTO) | _BV(TWEN); | |
248 return cnt; | |
249 } | |
250 | |
251 /* | |
252 * iic_write | |
253 * | |
254 * Write len bytes of data from address adr in slave sla into | |
255 * data. Presume that the slave auto-increments the address on | |
256 * successive writes. | |
257 * | |
258 * Returns the number of bytes read, or the following on failure. | |
259 * IIC_STFAIL Could generate START condition (broken bus or busy). | |
260 * IIC_FAILARB Failed bus arbitration. | |
261 * IIC_SLNAK Slave NAK'd. | |
262 * IIC_NOREPLY No reply (no such slave?) | |
263 * IIC_UNKNOWN Unexpected return from TWI reg. | |
264 * | |
265 * Heaviy cribbed from twitest.c by Joerg Wunsch | |
266 */ | |
267 int8_t | |
268 iic_write(uint8_t *data, uint8_t len, uint8_t adr, uint8_t sla) { | |
269 uint8_t twst, cnt; | |
270 | |
271 /* Generate START */ | |
272 TWCR = _BV(TWINT) | _BV(TWSTA) | _BV(TWEN); | |
273 | |
274 /* Spin waiting for START to be generated */ | |
275 while ((TWCR & _BV(TWINT)) == 0) | |
276 ; | |
277 switch (twst = TW_STATUS) { | |
278 case TW_REP_START: /* OK but shouldn't happen */ | |
279 case TW_START: | |
280 break; | |
281 | |
282 case TW_MT_ARB_LOST: | |
283 return IIC_FAILARB; | |
284 break; | |
285 | |
286 default: | |
287 /* Not in start condition, bail */ | |
288 return IIC_UNKNOWN; | |
289 } | |
290 #ifdef TWDEBUG | |
291 printf_P(PSTR("Sent START\r\n")); | |
292 #endif | |
293 | |
294 /* Send SLA+W */ | |
295 TWDR = sla | TW_WRITE; | |
296 TWCR = _BV(TWINT) | _BV(TWEN); | |
297 | |
298 /* Spin waiting for a response to be generated */ | |
299 while ((TWCR & _BV(TWINT)) == 0) | |
300 ; | |
301 | |
302 #ifdef TWDEBUG | |
303 printf_P(PSTR("Sent SLA+W\r\n")); | |
304 #endif | |
305 switch (twst = TW_STATUS) { | |
306 case TW_MT_SLA_ACK: | |
307 break; | |
308 | |
309 case TW_MT_SLA_NACK: | |
310 /* Send STOP */ | |
311 TWCR = _BV(TWINT) | _BV(TWSTO) | _BV(TWEN); | |
312 return IIC_SLNAK; | |
313 | |
314 case TW_MT_ARB_LOST: | |
315 return IIC_FAILARB; | |
316 break; | |
317 | |
318 default: | |
319 /* Send STOP */ | |
320 TWCR = _BV(TWINT) | _BV(TWSTO) | _BV(TWEN); | |
321 return IIC_UNKNOWN; | |
322 } | |
323 /* Send address */ | |
324 TWDR = adr; | |
325 TWCR = _BV(TWINT) | _BV(TWEN); | |
326 | |
327 /* Spin waiting for a response to be generated */ | |
328 while ((TWCR & _BV(TWINT)) == 0) | |
329 ; | |
330 #ifdef TWDEBUG | |
331 printf_P(PSTR("Sent address\r\n")); | |
332 #endif | |
333 switch ((twst = TW_STATUS)) { | |
334 case TW_MT_DATA_ACK: | |
335 break; | |
336 | |
337 case TW_MT_DATA_NACK: | |
338 /* Send STOP */ | |
339 TWCR = _BV(TWINT) | _BV(TWSTO) | _BV(TWEN); | |
340 return IIC_SLNAK; | |
341 | |
342 case TW_MT_ARB_LOST: | |
343 return IIC_FAILARB; | |
344 | |
345 default: | |
346 /* Send STOP */ | |
347 TWCR = _BV(TWINT) | _BV(TWSTO) | _BV(TWEN); | |
348 return IIC_UNKNOWN; | |
349 } | |
350 | |
351 cnt = 0; | |
352 for (; len > 0; len--) { | |
353 TWDR = *data++; | |
354 TWCR = _BV(TWINT) | _BV(TWEN); | |
355 | |
356 /* Spin waiting for a response to be generated */ | |
357 while ((TWCR & _BV(TWINT)) == 0) | |
358 ; | |
359 #ifdef TWDEBUG | |
360 printf_P(PSTR("Data sent\r\n")); | |
361 #endif | |
362 switch ((twst = TW_STATUS)) { | |
363 case TW_MT_DATA_NACK: | |
364 /* Send STOP */ | |
365 TWCR = _BV(TWINT) | _BV(TWSTO) | _BV(TWEN); | |
366 return cnt; | |
367 | |
368 case TW_MT_DATA_ACK: | |
369 cnt++; | |
370 break; | |
371 | |
372 default: | |
373 return IIC_UNKNOWN; | |
374 } | |
375 } | |
376 | |
377 /* Send STOP */ | |
378 TWCR = _BV(TWINT) | _BV(TWSTO) | _BV(TWEN); | |
379 return cnt; | |
380 } | |
381 | |
382 /* | |
383 * ds1307_gettod | |
384 * | |
385 * Read time of day from DS1307 into time | |
386 * | |
387 * Note that we canonify to 24hr mode. | |
388 * | |
389 */ | |
390 int8_t | |
391 ds1307_gettod(ds1307raw_t *time) { | |
392 int8_t len; | |
393 | |
394 len = iic_read((uint8_t *)time, sizeof(ds1307raw_t) + 1, 0, DS1307_ADR); | |
395 if (len < 0) { | |
396 printf_P(PSTR("iic_read failed - %d\r\n"), len); | |
397 return(0); | |
398 } | |
399 | |
400 #if 1 | |
401 if (len != sizeof(ds1307raw_t)) { | |
402 printf_P(PSTR("Only got %d bytes (vs %d)\r\n"), len, sizeof(ds1307raw_t)); | |
403 return(0); | |
404 } | |
405 #endif | |
406 | |
407 #ifdef TWDEBUG | |
408 int i; | |
409 | |
410 for (i = 0; i < len; i++) | |
411 printf_P(PSTR("0x%02x: 0x%02x\r\n"), i, *(((uint8_t *)time) + i)); | |
412 #endif | |
413 | |
414 return(1); | |
415 } | |
416 | |
417 /* | |
418 * ds1307_settod | |
419 * | |
420 * Set the DS1307 with the supplied time, format like so | |
421 * sc 2008/10/29 23:45:30 | |
422 * | |
423 */ | |
424 int8_t | |
425 ds1307_settod(char *date) { | |
426 ds1307raw_t rtime; | |
427 uint16_t year; | |
428 uint8_t i, month, day, hour, min, sec; | |
429 | |
430 if ((i = sscanf_P(date, PSTR("%hu/%hhd/%hhd %hhd:%hhd:%hhd"), &year, &month, &day, &hour, &min, &sec)) != 6) { | |
431 printf_P(PSTR("Can't parse date\r\n")); | |
432 return(0); | |
433 } | |
434 | |
435 if (year > 1900) | |
436 year -= 1900; | |
437 | |
438 rtime.split.year10 = year / 10; | |
439 rtime.split.year = year % 10; | |
440 rtime.split.month10 = month / 10; | |
441 rtime.split.month = month % 10; | |
442 rtime.split.day10 = day / 10; | |
443 rtime.split.day = day % 10; | |
444 rtime.split.pmam = ((hour / 10) & 0x02) >> 1; | |
445 rtime.split.hour10 = (hour / 10) & 0x01; | |
446 rtime.split.hour = hour % 10; | |
447 rtime.split.min10 = min / 10; | |
448 rtime.split.min = min % 10; | |
449 rtime.split.sec10 = sec / 10; | |
450 rtime.split.sec = sec % 10; | |
451 | |
452 rtime.split.ch = 0; // Enable clock | |
453 rtime.split.s1224 = 0; // 24 hour mode | |
454 rtime.split.dow = 0; // XXX: unused | |
455 rtime.split.out = 0; // No clock out | |
456 | |
457 #ifdef TWDEBUG | |
458 for (i = 0; i < sizeof(ds1307raw_t); i++) | |
459 printf_P(PSTR("0x%02x: 0x%02x\r\n"), i, *(((uint8_t *)&rtime) + i)); | |
460 #endif | |
461 if ((i = iic_write((uint8_t *)&rtime, sizeof(ds1307raw_t), 0, DS1307_ADR)) != sizeof(ds1307raw_t)) | |
462 printf_P(PSTR("Can't write to RTC, sent %d (vs %d)\r\n"), i, sizeof(ds1307raw_t)); | |
463 | |
464 return(1); | |
465 } | |
466 | |
467 /* | |
468 * ds1307_printtime | |
469 * | |
470 * Print the time in rtime with trailer | |
471 * | |
472 */ | |
473 void | |
474 ds1307_printtime(char *leader, char *trailer) { | |
475 ds1307raw_t rtime; | |
476 uint8_t hour; | |
477 | |
478 if (ds1307_gettod(&rtime) != 1) | |
479 return; | |
480 | |
481 // Handle 12/24 hour time | |
482 hour = rtime.split.hour10 * 10 + rtime.split.hour; | |
483 if (rtime.split.s1224) { | |
484 if (rtime.split.pmam) | |
485 hour += 12; | |
486 } else | |
487 hour += (rtime.split.pmam << 1) * 10; | |
488 | |
489 printf_P(PSTR("%S%04d/%02d/%02d %02d:%02d:%02d%S"), leader, | |
490 1900 + rtime.split.year10 * 10 + rtime.split.year, | |
491 rtime.split.month10 * 10 + rtime.split.month, | |
492 rtime.split.day10 * 10 + rtime.split.day, | |
493 hour, | |
494 rtime.split.min10 * 10 + rtime.split.min, | |
495 rtime.split.sec10 * 10 + rtime.split.sec, | |
496 trailer); | |
497 } |