Sylvain Munaut | 341542b | 2009-12-22 21:53:22 +0100 | [diff] [blame] | 1 | /* |
| 2 | * ubx-parse.c |
| 3 | * |
| 4 | * Implementation of parsing code converting UBX messages to GPS assist |
| 5 | * data |
| 6 | * |
| 7 | * |
| 8 | * Copyright (C) 2009 Sylvain Munaut <tnt@246tNt.com> |
| 9 | * |
| 10 | * This program is free software: you can redistribute it and/or modify |
| 11 | * it under the terms of the GNU General Public License as published by |
| 12 | * the Free Software Foundation, either version 2 of the License, or |
| 13 | * (at your option) any later version. |
| 14 | * |
| 15 | * This program is distributed in the hope that it will be useful, |
| 16 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 17 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 18 | * GNU General Public License for more details. |
| 19 | * |
| 20 | * You should have received a copy of the GNU General Public License |
| 21 | * along with this program. If not, see <http://www.gnu.org/licenses/>. |
| 22 | */ |
| 23 | |
| 24 | #include <stdio.h> |
| 25 | |
| 26 | #include "gps.h" |
| 27 | #include "ubx.h" |
| 28 | #include "ubx-parse.h" |
| 29 | |
Dieter Spaar | 5ffe5fe | 2012-07-18 22:18:16 +0200 | [diff] [blame] | 30 | #define DEBUG 1 |
| 31 | #if DEBUG |
| 32 | #define printd(x, args ...) printf(x, ## args) |
| 33 | #else |
| 34 | #define printd(x, args ...) |
| 35 | #endif |
| 36 | |
| 37 | #define DEBUG1 0 |
| 38 | #if DEBUG1 |
| 39 | #define printd1(x, args ...) printf(x, ## args) |
| 40 | #else |
| 41 | #define printd1(x, args ...) |
| 42 | #endif |
Sylvain Munaut | 341542b | 2009-12-22 21:53:22 +0100 | [diff] [blame] | 43 | |
| 44 | /* Helpers */ |
| 45 | |
| 46 | static int |
| 47 | float_to_fixedpoint(float f, int sf) |
| 48 | { |
| 49 | if (sf < 0) { |
| 50 | while (sf++ < 0) |
| 51 | f *= 2.0f; |
| 52 | } else { |
| 53 | while (sf-- > 0) |
| 54 | f *= 0.5f; |
| 55 | } |
| 56 | |
| 57 | return (int)f; |
| 58 | } |
| 59 | |
| 60 | static inline int |
| 61 | double_to_fixedpoint(double d, int sf) |
| 62 | { |
| 63 | if (sf < 0) { |
| 64 | while (sf++ < 0) |
| 65 | d *= 2.0; |
| 66 | } else { |
| 67 | while (sf-- > 0) |
| 68 | d *= 0.5; |
| 69 | } |
| 70 | |
| 71 | return (int)d; |
| 72 | } |
| 73 | |
| 74 | |
| 75 | /* UBX message parsing to fill gps assist data */ |
| 76 | |
| 77 | static void |
| 78 | _ubx_msg_parse_nav_posllh(struct ubx_hdr *hdr, void *pl, int pl_len, void *ud) |
| 79 | { |
| 80 | struct ubx_nav_posllh *nav_posllh = pl; |
| 81 | struct gps_assist_data *gps = ud; |
| 82 | |
Dieter Spaar | 5ffe5fe | 2012-07-18 22:18:16 +0200 | [diff] [blame] | 83 | printd("[.] NAV_POSLLH\n"); |
Sylvain Munaut | 341542b | 2009-12-22 21:53:22 +0100 | [diff] [blame] | 84 | |
Sylvain Munaut | 9819d8b | 2009-12-28 14:51:08 +0100 | [diff] [blame] | 85 | gps->fields |= GPS_FIELD_REFPOS; |
| 86 | |
| 87 | gps->ref_pos.latitude = (double)(nav_posllh->lat) * 1e-7; |
| 88 | gps->ref_pos.longitude = (double)(nav_posllh->lon) * 1e-7; |
| 89 | gps->ref_pos.altitude = (double)(nav_posllh->height) * 1e-3; |
Dieter Spaar | 5ffe5fe | 2012-07-18 22:18:16 +0200 | [diff] [blame] | 90 | |
| 91 | printd(" TOW %lu\n", nav_posllh->itow); |
| 92 | printd(" latitude %f\n", gps->ref_pos.latitude); |
| 93 | printd(" longitude %f\n", gps->ref_pos.longitude); |
| 94 | printd(" altitude %f\n", gps->ref_pos.altitude); |
Sylvain Munaut | 341542b | 2009-12-22 21:53:22 +0100 | [diff] [blame] | 95 | } |
| 96 | |
| 97 | static void |
| 98 | _ubx_msg_parse_aid_ini(struct ubx_hdr *hdr, void *pl, int pl_len, void *ud) |
| 99 | { |
| 100 | struct ubx_aid_ini *aid_ini = pl; |
| 101 | struct gps_assist_data *gps = ud; |
| 102 | |
Dieter Spaar | 5ffe5fe | 2012-07-18 22:18:16 +0200 | [diff] [blame] | 103 | printd("[.] AID_INI\n"); |
Sylvain Munaut | 341542b | 2009-12-22 21:53:22 +0100 | [diff] [blame] | 104 | |
Sylvain Munaut | 9c3ae67 | 2009-12-28 15:49:29 +0100 | [diff] [blame] | 105 | /* Extract info for "Reference Time" */ |
| 106 | gps->fields |= GPS_FIELD_REFTIME; |
| 107 | |
| 108 | gps->ref_time.wn = aid_ini->wn; |
| 109 | gps->ref_time.tow = (double)aid_ini->tow * 1e-3; |
Dieter Spaar | 5ffe5fe | 2012-07-18 22:18:16 +0200 | [diff] [blame] | 110 | gps->ref_time.when = time(NULL); |
| 111 | |
| 112 | printd(" WN %d\n", gps->ref_time.wn); |
| 113 | printd(" TOW %ld\n", aid_ini->tow); |
| 114 | |
| 115 | if((aid_ini->flags & 0x03) != 0x03) { /* time and pos valid ? */ |
| 116 | fprintf(stderr, "Postion and/or time not valid (0x%lx)", aid_ini->flags); |
| 117 | } |
| 118 | |
Sylvain Munaut | 639889b | 2009-12-28 15:34:30 +0100 | [diff] [blame] | 119 | // FIXME: We could extract ref position as well but we need it in |
| 120 | // WGS84 geodetic coordinates and it's provided as ecef, so |
| 121 | // we need a lot of math ... |
Sylvain Munaut | 341542b | 2009-12-22 21:53:22 +0100 | [diff] [blame] | 122 | } |
| 123 | |
| 124 | static void |
| 125 | _ubx_msg_parse_aid_hui(struct ubx_hdr *hdr, void *pl, int pl_len, void *ud) |
| 126 | { |
| 127 | struct ubx_aid_hui *aid_hui = pl; |
| 128 | struct gps_assist_data *gps = ud; |
| 129 | |
Dieter Spaar | 5ffe5fe | 2012-07-18 22:18:16 +0200 | [diff] [blame] | 130 | printd("[.] AID_HUI\n"); |
Sylvain Munaut | 341542b | 2009-12-22 21:53:22 +0100 | [diff] [blame] | 131 | |
| 132 | if (aid_hui->flags & 0x2) { /* UTC parameters valid */ |
| 133 | struct gps_utc_model *utc = &gps->utc; |
| 134 | |
Dieter Spaar | 5ffe5fe | 2012-07-18 22:18:16 +0200 | [diff] [blame] | 135 | printd(" UTC\n"); |
| 136 | |
Sylvain Munaut | 341542b | 2009-12-22 21:53:22 +0100 | [diff] [blame] | 137 | gps->fields |= GPS_FIELD_UTC; |
| 138 | |
| 139 | utc->a0 = double_to_fixedpoint(aid_hui->utc_a0, -30); |
| 140 | utc->a1 = double_to_fixedpoint(aid_hui->utc_a1, -50); |
| 141 | utc->delta_t_ls = aid_hui->utc_ls; |
| 142 | utc->t_ot = aid_hui->utc_tot >> 12; |
| 143 | utc->wn_t = aid_hui->utc_wnt; |
| 144 | utc->wn_lsf = aid_hui->utc_wnf; |
| 145 | utc->dn = aid_hui->utc_dn; |
| 146 | utc->delta_t_lsf = aid_hui->utc_lsf; |
| 147 | } |
| 148 | |
| 149 | if (aid_hui->flags & 0x04) { /* Klobuchar parameters valid */ |
| 150 | struct gps_ionosphere_model *iono = &gps->ionosphere; |
| 151 | |
Dieter Spaar | 5ffe5fe | 2012-07-18 22:18:16 +0200 | [diff] [blame] | 152 | printd(" IONOSPHERE\n"); |
| 153 | |
Sylvain Munaut | 341542b | 2009-12-22 21:53:22 +0100 | [diff] [blame] | 154 | gps->fields |= GPS_FIELD_IONOSPHERE; |
| 155 | |
| 156 | iono->alpha_0 = float_to_fixedpoint(aid_hui->klob_a0, -30); |
| 157 | iono->alpha_1 = float_to_fixedpoint(aid_hui->klob_a1, -27); |
| 158 | iono->alpha_2 = float_to_fixedpoint(aid_hui->klob_a2, -24); |
| 159 | iono->alpha_3 = float_to_fixedpoint(aid_hui->klob_a3, -24); |
| 160 | iono->beta_0 = float_to_fixedpoint(aid_hui->klob_b0, 11); |
| 161 | iono->beta_1 = float_to_fixedpoint(aid_hui->klob_b1, 14); |
| 162 | iono->beta_2 = float_to_fixedpoint(aid_hui->klob_b2, 16); |
| 163 | iono->beta_3 = float_to_fixedpoint(aid_hui->klob_b3, 16); |
| 164 | } |
| 165 | } |
| 166 | |
| 167 | static void |
| 168 | _ubx_msg_parse_aid_alm(struct ubx_hdr *hdr, void *pl, int pl_len, void *ud) |
| 169 | { |
| 170 | struct ubx_aid_alm *aid_alm = pl; |
| 171 | struct gps_assist_data *gps = ud; |
| 172 | |
Dieter Spaar | 5ffe5fe | 2012-07-18 22:18:16 +0200 | [diff] [blame] | 173 | if(pl_len == 8) /* length if not available */ |
| 174 | return; |
| 175 | |
| 176 | if(pl_len != sizeof(struct ubx_aid_alm)) { |
| 177 | fprintf(stderr, "pl_len != sizeof(struct ubx_aid_alm) (%d)\n", pl_len); |
| 178 | return; |
| 179 | } |
| 180 | |
| 181 | printd("[.] AID_ALM %2ld - %ld (nsv = %d)\n", aid_alm->sv_id, aid_alm->gps_week, gps->almanac.n_sv); |
Sylvain Munaut | 341542b | 2009-12-22 21:53:22 +0100 | [diff] [blame] | 182 | |
| 183 | if (aid_alm->gps_week) { |
Dieter Spaar | 5ffe5fe | 2012-07-18 22:18:16 +0200 | [diff] [blame] | 184 | int i = gps->almanac.n_sv++; |
Sylvain Munaut | 341542b | 2009-12-22 21:53:22 +0100 | [diff] [blame] | 185 | gps->fields |= GPS_FIELD_ALMANAC; |
| 186 | gps->almanac.wna = aid_alm->gps_week & 0xff; |
Dieter Spaar | 5ffe5fe | 2012-07-18 22:18:16 +0200 | [diff] [blame] | 187 | gps_unpack_sf45_almanac(aid_alm->alm_words, &gps->almanac.svs[i]); |
| 188 | /* set satellite ID this way, otherwise it will be wrong */ |
| 189 | gps->almanac.svs[i].sv_id = aid_alm->sv_id; |
Sylvain Munaut | 341542b | 2009-12-22 21:53:22 +0100 | [diff] [blame] | 190 | } |
| 191 | } |
| 192 | |
| 193 | static void |
| 194 | _ubx_msg_parse_aid_eph(struct ubx_hdr *hdr, void *pl, int pl_len, void *ud) |
| 195 | { |
| 196 | struct ubx_aid_eph *aid_eph = pl; |
| 197 | struct gps_assist_data *gps = ud; |
| 198 | |
Dieter Spaar | 5ffe5fe | 2012-07-18 22:18:16 +0200 | [diff] [blame] | 199 | if(pl_len == 8) /* length if not available */ |
| 200 | return; |
| 201 | |
| 202 | if(pl_len != sizeof(struct ubx_aid_eph)) { |
| 203 | fprintf(stderr, "pl_len != sizeof(struct ubx_aid_eph) (%d)\n", pl_len); |
| 204 | return; |
| 205 | } |
| 206 | |
| 207 | printd("[.] AID_EPH %2ld - %s (nsv = %d)\n", aid_eph->sv_id, aid_eph->present ? "present" : "", gps->ephemeris.n_sv); |
Sylvain Munaut | 341542b | 2009-12-22 21:53:22 +0100 | [diff] [blame] | 208 | |
| 209 | if (aid_eph->present) { |
| 210 | int i = gps->ephemeris.n_sv++; |
| 211 | gps->fields |= GPS_FIELD_EPHEMERIS; |
| 212 | gps->ephemeris.svs[i].sv_id = aid_eph->sv_id; |
| 213 | gps_unpack_sf123(aid_eph->eph_words, &gps->ephemeris.svs[i]); |
| 214 | } |
| 215 | } |
| 216 | |
| 217 | |
Dieter Spaar | d652a32 | 2012-07-18 22:18:42 +0200 | [diff] [blame^] | 218 | static void |
| 219 | _ubx_msg_parse_nav_timegps(struct ubx_hdr *hdr, void *pl, int pl_len, void *ud) |
| 220 | { |
| 221 | struct ubx_nav_timegps *nav_timegps = pl; |
| 222 | struct gps_assist_data *gps = ud; |
| 223 | |
| 224 | printd1("[.] NAV_TIMEGPS\n"); |
| 225 | |
| 226 | /* Extract info for "Reference Time" */ |
| 227 | gps->fields |= GPS_FIELD_REFTIME; |
| 228 | |
| 229 | gps->ref_time.wn = nav_timegps->week; |
| 230 | gps->ref_time.tow = (double)nav_timegps->itow * 1e-3; |
| 231 | gps->ref_time.when = time(NULL); |
| 232 | |
| 233 | printd1(" WN %d\n", nav_timegps->week); |
| 234 | printd1(" TOW %ld\n", nav_timegps->itow); |
| 235 | } |
| 236 | |
Sylvain Munaut | 341542b | 2009-12-22 21:53:22 +0100 | [diff] [blame] | 237 | /* Dispatch table */ |
| 238 | struct ubx_dispatch_entry ubx_parse_dt[] = { |
| 239 | UBX_DISPATCH(NAV, POSLLH, _ubx_msg_parse_nav_posllh), |
| 240 | UBX_DISPATCH(AID, INI, _ubx_msg_parse_aid_ini), |
| 241 | UBX_DISPATCH(AID, HUI, _ubx_msg_parse_aid_hui), |
| 242 | UBX_DISPATCH(AID, ALM, _ubx_msg_parse_aid_alm), |
| 243 | UBX_DISPATCH(AID, EPH, _ubx_msg_parse_aid_eph), |
Dieter Spaar | d652a32 | 2012-07-18 22:18:42 +0200 | [diff] [blame^] | 244 | UBX_DISPATCH(NAV, TIMEGPS, _ubx_msg_parse_nav_timegps), |
Sylvain Munaut | 341542b | 2009-12-22 21:53:22 +0100 | [diff] [blame] | 245 | }; |
| 246 | |