2 * Copyright © 2013 Keith Packard <keithp@keithp.com>
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation; version 2 of the License.
8 * This program is distributed in the hope that it will be useful, but
9 * WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * General Public License for more details.
13 * You should have received a copy of the GNU General Public License along
14 * with this program; if not, write to the Free Software Foundation, Inc.,
15 * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
22 #include "ao_gps_ublox.h"
24 __xdata uint8_t ao_gps_mutex;
25 __pdata uint16_t ao_gps_tick;
26 __xdata struct ao_telemetry_location ao_gps_data;
27 __xdata struct ao_telemetry_satellite ao_gps_tracking_data;
29 static const char ao_gps_set_nmea[] = "\r\n$PUBX,41,1,3,1,57600,0*2d\r\n";
31 const char ao_gps_config[] = {
35 struct ao_ublox_cksum {
39 static __pdata struct ao_ublox_cksum ao_ublox_cksum;
40 static __pdata uint16_t ao_ublox_len;
42 #ifndef ao_ublox_getchar
43 #define ao_ublox_getchar ao_serial1_getchar
44 #define ao_ublox_putchar ao_serial1_putchar
45 #define ao_ublox_set_speed ao_serial1_set_speed
48 #define ao_ublox_byte() ((uint8_t) ao_ublox_getchar())
50 static inline void add_cksum(struct ao_ublox_cksum *cksum, uint8_t c)
56 static void ao_ublox_init_cksum(void)
58 ao_ublox_cksum.a = ao_ublox_cksum.b = 0;
61 static void ao_ublox_putchar_cksum(uint8_t c)
63 add_cksum(&ao_ublox_cksum, c);
67 static uint8_t header_byte(void)
69 uint8_t c = ao_ublox_byte();
70 add_cksum(&ao_ublox_cksum, c);
74 static uint8_t data_byte(void)
80 static char __xdata *ublox_target;
82 static void ublox_u16(uint8_t offset)
84 uint16_t __xdata *ptr = (uint16_t __xdata *) (ublox_target + offset);
88 val |= data_byte () << 8;
92 static void ublox_u8(uint8_t offset)
94 uint8_t __xdata *ptr = (uint8_t __xdata *) (ublox_target + offset);
101 static void ublox_u32(uint8_t offset) __reentrant
103 uint32_t __xdata *ptr = (uint32_t __xdata *) (ublox_target + offset);
106 val = ((uint32_t) data_byte ());
107 val |= ((uint32_t) data_byte ()) << 8;
108 val |= ((uint32_t) data_byte ()) << 16;
109 val |= ((uint32_t) data_byte ()) << 24;
113 static void ublox_discard(uint8_t len)
120 #define UBLOX_DISCARD 1
125 struct ublox_packet_parse {
131 ao_ublox_parse(void __xdata *target, const struct ublox_packet_parse *parse) __reentrant
135 ublox_target = target;
137 offset = parse[i].offset;
138 switch (parse[i].type) {
142 ublox_discard(offset);
158 * NAV-DOP message parsing
161 static struct nav_dop {
167 static const struct ublox_packet_parse nav_dop_packet[] = {
168 { UBLOX_DISCARD, 6 }, /* 0 GPS Millisecond Time of Week, gDOP */
169 { UBLOX_U16, offsetof(struct nav_dop, pdop) }, /* 6 pDOP */
170 { UBLOX_DISCARD, 2 }, /* 8 tDOP */
171 { UBLOX_U16, offsetof(struct nav_dop, vdop) }, /* 10 vDOP */
172 { UBLOX_U16, offsetof(struct nav_dop, hdop) }, /* 12 hDOP */
173 { UBLOX_DISCARD, 4 }, /* 14 nDOP, eDOP */
178 ao_ublox_parse_nav_dop(void)
180 ao_ublox_parse(&nav_dop, nav_dop_packet);
184 * NAV-POSLLH message parsing
186 static struct nav_posllh {
192 static const struct ublox_packet_parse nav_posllh_packet[] = {
193 { UBLOX_DISCARD, 4 }, /* 0 GPS Millisecond Time of Week */
194 { UBLOX_U32, offsetof(struct nav_posllh, lon) }, /* 4 Longitude */
195 { UBLOX_U32, offsetof(struct nav_posllh, lat) }, /* 8 Latitude */
196 { UBLOX_DISCARD, 4 }, /* 12 Height above Ellipsoid */
197 { UBLOX_U32, offsetof(struct nav_posllh, alt_msl) }, /* 16 Height above mean sea level */
198 { UBLOX_DISCARD, 8 }, /* 20 hAcc, vAcc */
199 { UBLOX_END, 0 }, /* 28 */
203 ao_ublox_parse_nav_posllh(void)
205 ao_ublox_parse(&nav_posllh, nav_posllh_packet);
209 * NAV-SOL message parsing
211 static struct nav_sol {
217 static const struct ublox_packet_parse nav_sol_packet[] = {
218 { UBLOX_DISCARD, 10 }, /* 0 iTOW, fTOW, week */
219 { UBLOX_U8, offsetof(struct nav_sol, gps_fix) }, /* 10 gpsFix */
220 { UBLOX_U8, offsetof(struct nav_sol, flags) }, /* 11 flags */
221 { UBLOX_DISCARD, 35 }, /* 12 ecefX, ecefY, ecefZ, pAcc, ecefVX, ecefVY, ecefVZ, sAcc, pDOP, reserved1 */
222 { UBLOX_U8, offsetof(struct nav_sol, nsat) }, /* 47 numSV */
223 { UBLOX_DISCARD, 4 }, /* 48 reserved2 */
227 #define NAV_SOL_FLAGS_GPSFIXOK 0
228 #define NAV_SOL_FLAGS_DIFFSOLN 1
229 #define NAV_SOL_FLAGS_WKNSET 2
230 #define NAV_SOL_FLAGS_TOWSET 3
233 ao_ublox_parse_nav_sol(void)
235 ao_ublox_parse(&nav_sol, nav_sol_packet);
239 * NAV-SVINFO message parsing
242 static struct nav_svinfo {
247 static const struct ublox_packet_parse nav_svinfo_packet[] = {
248 { UBLOX_DISCARD, 4 }, /* 0 iTOW */
249 { UBLOX_U8, offsetof(struct nav_svinfo, num_ch) }, /* 4 numCh */
250 { UBLOX_U8, offsetof(struct nav_svinfo, flags) }, /* 5 globalFlags */
251 { UBLOX_DISCARD, 2 }, /* 6 reserved2 */
255 #define NAV_SVINFO_MAX_SAT 16
257 static struct nav_svinfo_sat {
263 } nav_svinfo_sat[NAV_SVINFO_MAX_SAT];
265 static uint8_t nav_svinfo_nsat;
267 static const struct ublox_packet_parse nav_svinfo_sat_packet[] = {
268 { UBLOX_U8, offsetof(struct nav_svinfo_sat, chn) }, /* 8 + 12*N chn */
269 { UBLOX_U8, offsetof(struct nav_svinfo_sat, svid) }, /* 9 + 12*N svid */
270 { UBLOX_U8, offsetof(struct nav_svinfo_sat, flags) }, /* 10 + 12*N flags */
271 { UBLOX_U8, offsetof(struct nav_svinfo_sat, quality) }, /* 11 + 12*N quality */
272 { UBLOX_U8, offsetof(struct nav_svinfo_sat, cno) }, /* 12 + 12*N cno */
273 { UBLOX_DISCARD, 7 }, /* 13 + 12*N elev, azim, prRes */
277 #define NAV_SVINFO_SAT_FLAGS_SVUSED 0
278 #define NAV_SVINFO_SAT_FLAGS_DIFFCORR 1
279 #define NAV_SVINFO_SAT_FLAGS_ORBITAVAIL 2
280 #define NAV_SVINFO_SAT_FLAGS_ORBITEPH 3
281 #define NAV_SVINFO_SAT_FLAGS_UNHEALTHY 4
282 #define NAV_SVINFO_SAT_FLAGS_ORBITALM 5
283 #define NAV_SVINFO_SAT_FLAGS_ORBITAOP 6
284 #define NAV_SVINFO_SAT_FLAGS_SMOOTHED 7
286 #define NAV_SVINFO_SAT_QUALITY_IDLE 0
287 #define NAV_SVINFO_SAT_QUALITY_SEARCHING 1
288 #define NAV_SVINFO_SAT_QUALITY_ACQUIRED 2
289 #define NAV_SVINFO_SAT_QUALITY_UNUSABLE 3
290 #define NAV_SVINFO_SAT_QUALITY_LOCKED 4
291 #define NAV_SVINFO_SAT_QUALITY_RUNNING 5
294 ao_ublox_parse_nav_svinfo(void)
298 ao_ublox_parse(&nav_svinfo, nav_svinfo_packet);
299 for (nsat = 0; nsat < nav_svinfo.num_ch && ao_ublox_len >= 12; nsat++) {
300 if (nsat < NAV_SVINFO_MAX_SAT) {
301 ao_ublox_parse(&nav_svinfo_sat[nav_svinfo_nsat++], nav_svinfo_sat_packet);
309 * NAV-TIMEUTC message parsing
311 static struct nav_timeutc {
321 #define NAV_TIMEUTC_VALID_TOW 0
322 #define NAV_TIMEUTC_VALID_WKN 1
323 #define NAV_TIMEUTC_VALID_UTC 2
325 static const struct ublox_packet_parse nav_timeutc_packet[] = {
326 { UBLOX_DISCARD, 12 }, /* 0 iTOW, tAcc, nano */
327 { UBLOX_U16, offsetof(struct nav_timeutc, year) }, /* 12 year */
328 { UBLOX_U8, offsetof(struct nav_timeutc, month) }, /* 14 month */
329 { UBLOX_U8, offsetof(struct nav_timeutc, day) }, /* 15 day */
330 { UBLOX_U8, offsetof(struct nav_timeutc, hour) }, /* 16 hour */
331 { UBLOX_U8, offsetof(struct nav_timeutc, min) }, /* 17 min */
332 { UBLOX_U8, offsetof(struct nav_timeutc, sec) }, /* 18 sec */
333 { UBLOX_U8, offsetof(struct nav_timeutc, valid) }, /* 19 valid */
338 ao_ublox_parse_nav_timeutc(void)
340 ao_ublox_parse(&nav_timeutc, nav_timeutc_packet);
344 * NAV-VELNED message parsing
347 static struct nav_velned {
353 static const struct ublox_packet_parse nav_velned_packet[] = {
354 { UBLOX_DISCARD, 12 }, /* 0 iTOW, velN, velE */
355 { UBLOX_U32, offsetof(struct nav_velned, vel_d) }, /* 12 velD */
356 { UBLOX_DISCARD, 4 }, /* 16 speed */
357 { UBLOX_U32, offsetof(struct nav_velned, g_speed) }, /* 20 gSpeed */
358 { UBLOX_U32, offsetof(struct nav_velned, heading) }, /* 24 heading */
359 { UBLOX_DISCARD, 8 }, /* 28 sAcc, cAcc */
364 ao_ublox_parse_nav_velned(void)
366 ao_ublox_parse(&nav_velned, nav_velned_packet);
370 * Set the protocol mode and baud rate
377 ao_ublox_set_speed(AO_SERIAL_SPEED_9600);
380 * A bunch of nulls so the start bit
383 for (i = 0; i < 64; i++)
384 ao_ublox_putchar(0x00);
387 * Send the baud-rate setting and protocol-setting
388 * command three times
390 for (k = 0; k < 3; k++)
391 for (i = 0; i < sizeof (ao_gps_set_nmea); i++)
392 ao_ublox_putchar(ao_gps_set_nmea[i]);
395 * Increase the baud rate
397 ao_ublox_set_speed(AO_SERIAL_SPEED_57600);
400 * Pad with nulls to give the chip
401 * time to see the baud rate switch
403 for (i = 0; i < 64; i++)
404 ao_ublox_putchar(0x00);
408 ao_ublox_putstart(uint8_t class, uint8_t id, uint16_t len)
410 ao_ublox_init_cksum();
411 ao_ublox_putchar(0xb5);
412 ao_ublox_putchar(0x62);
413 ao_ublox_putchar_cksum(class);
414 ao_ublox_putchar_cksum(id);
415 ao_ublox_putchar_cksum(len);
416 ao_ublox_putchar_cksum(len >> 8);
420 ao_ublox_putend(void)
422 ao_ublox_putchar(ao_ublox_cksum.a);
423 ao_ublox_putchar(ao_ublox_cksum.b);
427 ao_ublox_set_message_rate(uint8_t class, uint8_t msgid, uint8_t rate)
429 ao_ublox_putstart(0x06, 0x01, 3);
430 ao_ublox_putchar_cksum(class);
431 ao_ublox_putchar_cksum(msgid);
432 ao_ublox_putchar_cksum(rate);
437 * Disable all MON message
439 static const uint8_t ublox_disable_mon[] = {
440 0x0b, 0x09, 0x02, 0x06, 0x07, 0x21, 0x08, 0x04
444 * Disable all NAV messages. The desired
445 * ones will be explicitly re-enabled
448 static const uint8_t ublox_disable_nav[] = {
449 0x60, 0x22, 0x31, 0x04, 0x40, 0x01, 0x02, 0x32,
450 0x06, 0x03, 0x30, 0x20, 0x21, 0x11, 0x12
454 * Enable enough messages to get all of the data we want
456 static const uint8_t ublox_enable_nav[] = {
466 ao_gps(void) __reentrant
469 struct ao_ublox_cksum cksum;
474 /* Disable all messages */
475 for (i = 0; i < sizeof (ublox_disable_mon); i++)
476 ao_ublox_set_message_rate(0x0a, ublox_disable_mon[i], 0);
477 for (i = 0; i < sizeof (ublox_disable_nav); i++)
478 ao_ublox_set_message_rate(UBLOX_NAV, ublox_disable_nav[i], 0);
480 /* Enable all of the messages we want */
481 for (i = 0; i < sizeof (ublox_enable_nav); i++)
482 ao_ublox_set_message_rate(UBLOX_NAV, ublox_enable_nav[i], 1);
485 /* Locate the begining of the next record */
486 while (ao_ublox_byte() != (uint8_t) 0xb5)
488 if (ao_ublox_byte() != (uint8_t) 0x62)
491 ao_ublox_init_cksum();
493 class = header_byte();
497 ao_ublox_len = header_byte();
498 ao_ublox_len |= header_byte() << 8;
500 if (ao_ublox_len > 1023)
507 if (ao_ublox_len != 18)
509 ao_ublox_parse_nav_dop();
511 case UBLOX_NAV_POSLLH:
512 if (ao_ublox_len != 28)
514 ao_ublox_parse_nav_posllh();
517 if (ao_ublox_len != 52)
519 ao_ublox_parse_nav_sol();
521 case UBLOX_NAV_SVINFO:
522 if (ao_ublox_len < 8)
524 ao_ublox_parse_nav_svinfo();
526 case UBLOX_NAV_VELNED:
527 if (ao_ublox_len != 36)
529 ao_ublox_parse_nav_velned();
531 case UBLOX_NAV_TIMEUTC:
532 if (ao_ublox_len != 20)
534 ao_ublox_parse_nav_timeutc();
540 if (ao_ublox_len != 0)
543 /* verify checksum and end sequence */
544 cksum.a = ao_ublox_byte();
545 cksum.b = ao_ublox_byte();
546 if (ao_ublox_cksum.a != cksum.a || ao_ublox_cksum.b != cksum.b)
553 ao_mutex_get(&ao_gps_mutex);
554 ao_gps_tick = ao_time();
556 ao_gps_data.flags = 0;
557 ao_gps_data.flags |= AO_GPS_RUNNING;
558 if (nav_sol.gps_fix & (1 << NAV_SOL_FLAGS_GPSFIXOK)) {
559 uint8_t nsat = nav_sol.nsat;
560 ao_gps_data.flags |= AO_GPS_VALID;
563 ao_gps_data.flags |= nsat;
565 if (nav_timeutc.valid & (1 << NAV_TIMEUTC_VALID_UTC))
566 ao_gps_data.flags |= AO_GPS_DATE_VALID;
568 ao_gps_data.altitude = nav_posllh.alt_msl / 1000;
569 ao_gps_data.latitude = nav_posllh.lat;
570 ao_gps_data.longitude = nav_posllh.lon;
572 ao_gps_data.year = nav_timeutc.year - 2000;
573 ao_gps_data.month = nav_timeutc.month;
574 ao_gps_data.day = nav_timeutc.day;
576 ao_gps_data.hour = nav_timeutc.hour;
577 ao_gps_data.minute = nav_timeutc.min;
578 ao_gps_data.second = nav_timeutc.sec;
580 ao_gps_data.pdop = nav_dop.pdop;
581 ao_gps_data.hdop = nav_dop.hdop;
582 ao_gps_data.vdop = nav_dop.vdop;
584 /* mode is not set */
586 ao_gps_data.ground_speed = nav_velned.g_speed;
587 ao_gps_data.climb_rate = -nav_velned.vel_d;
588 ao_gps_data.course = nav_velned.heading / 200000;
590 ao_gps_tracking_data.channels = 0;
592 struct ao_telemetry_satellite_info *dst = &ao_gps_tracking_data.sats[0];
594 for (i = 0; i < nav_svinfo_nsat; i++) {
595 struct nav_svinfo_sat *src = &nav_svinfo_sat[i];
597 if (!(src->flags & (1 << NAV_SVINFO_SAT_FLAGS_UNHEALTHY)) &&
598 src->quality >= NAV_SVINFO_SAT_QUALITY_ACQUIRED)
600 dst->svid = src->svid;
601 dst->c_n_1 = src->cno;
603 ao_gps_tracking_data.channels++;
607 ao_mutex_put(&ao_gps_mutex);
608 ao_wakeup(&ao_gps_data);
609 ao_wakeup(&ao_gps_tracking_data);
617 __xdata struct ao_task ao_gps_task;
622 ao_add_task(&ao_gps_task, ao_gps, "gps");