2 * Copyright © 2009 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 <sys/types.h>
25 #define AO_GPS_NUM_SAT_MASK (0xf << 0)
26 #define AO_GPS_NUM_SAT_SHIFT (0)
28 #define AO_GPS_VALID (1 << 4)
35 int32_t latitude; /* degrees * 10⁷ */
36 int32_t longitude; /* degrees * 10⁷ */
37 int16_t altitude; /* m */
38 uint16_t ground_speed; /* cm/s */
39 uint8_t course; /* degrees / 2 */
40 uint8_t hdop; /* * 5 */
41 int16_t climb_rate; /* cm/s */
42 uint16_t h_error; /* m */
43 uint16_t v_error; /* m */
47 ao_mutex_get(uint8_t *mutex)
52 ao_mutex_put(uint8_t *mutex)
68 sprintf (line, "\\%02x", ((int) c) & 0xff);
70 sprintf (line, "%c", c);
72 write(1, line, strlen(line));
75 #define QUEUE_LEN 4096
77 static char input_queue[QUEUE_LEN];
78 int input_head, input_tail;
82 check_sirf_message(char *from, uint8_t *msg, int len)
84 uint16_t encoded_len, encoded_cksum;
89 if (msg[0] != 0xa0 || msg[1] != 0xa2) {
90 printf ("bad header\n");
97 if (msg[len-1] != 0xb3 || msg[len-2] != 0xb0) {
98 printf ("bad trailer\n");
101 encoded_len = (msg[2] << 8) | msg[3];
103 if (encoded_len != len - 8) {
104 printf ("length mismatch (got %d, wanted %d)\n",
105 len - 8, encoded_len);
108 encoded_cksum = (msg[len - 4] << 8) | msg[len-3];
110 for (i = 4; i < len - 4; i++)
111 cksum = (cksum + msg[i]) & 0x7fff;
112 if (encoded_cksum != cksum) {
113 printf ("cksum mismatch (got %04x wanted %04x)\n",
114 cksum, encoded_cksum);
142 int16_t heading_rate;
148 #define get_u8(u) u = (msg[off]); off+= 1
149 #define get_u16(u) u = (msg[off] << 8) | (msg[off + 1]); off+= 2
150 #define get_u32(u) u = (msg[off] << 24) | (msg[off + 1] << 16) | (msg[off+2] << 8) | (msg[off+3]); off+= 4
173 get_u16(heading_rate);
180 printf ("Geodetic Navigation Data (41):\n");
181 printf ("\tNav valid %04x\n", nav_valid);
182 printf ("\tNav type %04x\n", nav_type);
183 printf ("\tWeek %d\n", week);
184 printf ("\tTOW %d\n", tow);
185 printf ("\tyear %d\n", year);
186 printf ("\tmonth %d\n", month);
187 printf ("\tday %d\n", day);
188 printf ("\thour %d\n", hour);
189 printf ("\tminute %d\n", minute);
190 printf ("\tsecond %g\n", second / 1000.0);
191 printf ("\tsats: %08x\n", sat_list);
192 printf ("\tlat: %g\n", lat / 1.0e7);
193 printf ("\tlon: %g\n", lon / 1.0e7);
194 printf ("\talt_ell: %g\n", alt_ell / 100.0);
195 printf ("\talt_msll: %g\n", alt_msl / 100.0);
196 printf ("\tdatum: %d\n", datum);
197 printf ("\tground speed: %g\n", sog / 100.0);
198 printf ("\tcourse: %g\n", cog / 100.0);
199 printf ("\tclimb: %g\n", climb_rate / 100.0);
200 printf ("\theading rate: %g\n", heading_rate / 100.0);
201 printf ("\th error: %g\n", h_error / 100.0);
202 printf ("\tv error: %g\n", v_error / 100.0);
203 printf ("\tt error: %g\n", t_error / 100.0);
204 printf ("\th vel error: %g\n", h_v_error / 100.0);
207 printf ("%s %4d:", from, encoded_len);
208 for (i = 4; i < len - 4; i++) {
209 if (((i - 4) & 0xf) == 0)
211 printf (" %3d", msg[i]);
217 static uint8_t sirf_message[4096];
218 static int sirf_message_len;
219 static uint8_t sirf_in_message[4096];
220 static int sirf_in_len;
223 ao_serial_getchar(void)
228 while (input_head == input_tail) {
230 input_tail = read(ao_gps_fd, input_queue, QUEUE_LEN);
231 if (input_tail < 0) {
232 if (errno == EINTR || errno == EAGAIN)
241 c = input_queue[input_head];
242 input_head = (input_head + 1) % QUEUE_LEN;
244 if (sirf_in_len || uc == 0xa0) {
245 if (sirf_in_len < 4096)
246 sirf_in_message[sirf_in_len++] = uc;
248 check_sirf_message("recv", sirf_in_message, sirf_in_len);
257 ao_serial_putchar(char c)
260 uint8_t uc = (uint8_t) c;
262 if (sirf_message_len || uc == 0xa0) {
263 if (sirf_message_len < 4096)
264 sirf_message[sirf_message_len++] = uc;
266 check_sirf_message("send", sirf_message, sirf_message_len);
267 sirf_message_len = 0;
271 i = write(ao_gps_fd, &c, 1);
273 if ((uint8_t) c == 0xb3 || c == '\r') {
274 static const struct timespec delay = {
276 .tv_nsec = 100 * 1000 * 1000
279 // nanosleep(&delay, NULL);
283 if (i < 0 && (errno == EINTR || errno == EAGAIN))
290 #define AO_SERIAL_SPEED_4800 0
291 #define AO_SERIAL_SPEED_57600 1
294 ao_serial_set_speed(uint8_t speed)
297 struct termios termios;
300 tcgetattr(fd, &termios);
302 case AO_SERIAL_SPEED_4800:
303 cfsetspeed(&termios, B4800);
305 case AO_SERIAL_SPEED_57600:
306 cfsetspeed(&termios, B57600);
309 tcsetattr(fd, TCSAFLUSH, &termios);
310 tcflush(fd, TCIFLUSH);
313 #include "ao_gps_print.c"
320 printf ("%02d:%02d:%02d",
321 ao_gps_data.hour, ao_gps_data.minute,
323 printf (" nsat %d %svalid",
324 ao_gps_data.flags & AO_GPS_NUM_SAT_MASK,
325 ao_gps_data.flags & AO_GPS_VALID ? "" : "not ");
326 printf (" lat %g lon %g alt %d",
327 ao_gps_data.latitude / 1.0e7,
328 ao_gps_data.longitude / 1.0e7,
329 ao_gps_data.altitude);
330 printf (" speed %g climb %g course %d",
331 ao_gps_data.ground_speed / 100.0,
332 ao_gps_data.climb_rate / 100.0,
333 ao_gps_data.course * 2);
334 printf (" hdop %g h_error %d v_error %d",
335 ao_gps_data.hdop / 5.0,
336 ao_gps_data.h_error, ao_gps_data.v_error);
341 ao_gps_open(const char *tty)
343 struct termios termios;
346 fd = open (tty, O_RDWR);
350 tcgetattr(fd, &termios);
352 cfsetspeed(&termios, B4800);
353 tcsetattr(fd, TCSAFLUSH, &termios);
356 tcflush(fd, TCIFLUSH);
361 main (int argc, char **argv)
363 char *gps_file = "/dev/ttyUSB0";
365 ao_gps_fd = ao_gps_open(gps_file);