Details | Last modification | View Log | RSS feed
| Rev | Author | Line No. | Line |
|---|---|---|---|
| 684 | killagreg | 1 | #include <inttypes.h> |
| 2 | #include "ubx.h" |
||
| 702 | killagreg | 3 | #include "main.h" |
| 4 | #include <avr/io.h> |
||
| 684 | killagreg | 5 | |
| 6 | // ubx protocol parser state machine |
||
| 7 | #define UBXSTATE_IDLE 0 |
||
| 8 | #define UBXSTATE_SYNC1 1 |
||
| 9 | #define UBXSTATE_SYNC2 2 |
||
| 10 | #define UBXSTATE_CLASS 3 |
||
| 11 | #define UBXSTATE_LEN1 4 |
||
| 12 | #define UBXSTATE_LEN2 5 |
||
| 13 | #define UBXSTATE_DATA 6 |
||
| 14 | #define UBXSTATE_CKA 7 |
||
| 15 | #define UBXSTATE_CKB 8 |
||
| 16 | |||
| 17 | // ublox protocoll identifier |
||
| 18 | #define UBX_CLASS_NAV 0x01 |
||
| 19 | #define UBX_ID_POSLLH 0x02 |
||
| 20 | #define UBX_ID_POSUTM 0x08 |
||
| 21 | #define UBX_ID_STATUS 0x03 |
||
| 22 | #define UBX_ID_VELNED 0x12 |
||
| 23 | #define UBX_SYNC1_CHAR 0xB5 |
||
| 24 | #define UBX_SYNC2_CHAR 0x62 |
||
| 25 | |||
| 26 | |||
| 27 | typedef struct { |
||
| 28 | uint32_t ITOW; // ms GPS Millisecond Time of Week |
||
| 29 | uint8_t GPSfix; // GPSfix Type, range 0..6 |
||
| 30 | uint8_t Flags; // Navigation Status Flags |
||
| 31 | uint8_t DiffS; // Differential Status |
||
| 32 | uint8_t res; // reserved |
||
| 33 | uint32_t TTFF; // Time to first fix (millisecond time tag) |
||
| 34 | uint32_t MSSS; // Milliseconds since Startup / Reset |
||
| 702 | killagreg | 35 | uint8_t Status; |
| 684 | killagreg | 36 | } GPS_STATUS_t; |
| 37 | |||
| 38 | typedef struct { |
||
| 39 | uint32_t ITOW; // ms GPS Millisecond Time of Week |
||
| 40 | int32_t LON; // 1e-07 deg Longitude |
||
| 41 | int32_t LAT; // 1e-07 deg Latitude |
||
| 42 | int32_t HEIGHT; // mm Height above Ellipsoid |
||
| 43 | int32_t HMSL; // mm Height above mean sea level |
||
| 44 | uint32_t Hacc; // mm Horizontal Accuracy Estimate |
||
| 45 | uint32_t Vacc; // mm Vertical Accuracy Estimate |
||
| 702 | killagreg | 46 | uint8_t Status; |
| 684 | killagreg | 47 | } GPS_POSLLH_t; |
| 48 | |||
| 49 | typedef struct { |
||
| 50 | uint32_t ITOW; // ms GPS Millisecond Time of Week |
||
| 51 | int32_t EAST; // cm UTM Easting |
||
| 52 | int32_t NORTH; // cm UTM Nording |
||
| 53 | int32_t ALT; // cm altitude |
||
| 54 | uint8_t ZONE; // UTM zone number |
||
| 55 | uint8_t HEM; // Hemisphere Indicator (0=North, 1=South) |
||
| 702 | killagreg | 56 | uint8_t Status; |
| 684 | killagreg | 57 | } GPS_POSUTM_t; |
| 58 | |||
| 59 | typedef struct { |
||
| 60 | uint32_t ITOW; // ms GPS Millisecond Time of Week |
||
| 61 | int32_t VEL_N; // cm/s NED north velocity |
||
| 62 | int32_t VEL_E; // cm/s NED east velocity |
||
| 63 | int32_t VEL_D; // cm/s NED down velocity |
||
| 64 | uint32_t Speed; // cm/s Speed (3-D) |
||
| 65 | uint32_t GSpeed; // cm/s Ground Speed (2-D) |
||
| 66 | int32_t Heading; // 1e-05 deg Heading 2-D |
||
| 67 | uint32_t SAcc; // cm/s Speed Accuracy Estimate |
||
| 68 | uint32_t CAcc; // deg Course / Heading Accuracy Estimate |
||
| 702 | killagreg | 69 | uint8_t Status; |
| 684 | killagreg | 70 | } GPS_VELNED_t; |
| 71 | |||
| 72 | |||
| 73 | GPS_STATUS_t GpsStatus; |
||
| 74 | GPS_POSLLH_t GpsPosLlh; |
||
| 75 | GPS_POSUTM_t GpsPosUtm; |
||
| 76 | GPS_VELNED_t GpsVelNed; |
||
| 77 | |||
| 702 | killagreg | 78 | GPS_INFO_t GPSInfo; |
| 684 | killagreg | 79 | |
| 80 | void UpdateGPSInfo (void) |
||
| 81 | { |
||
| 702 | killagreg | 82 | if (GpsStatus.Status == VALID) // valid packet |
| 684 | killagreg | 83 | { |
| 702 | killagreg | 84 | GPSInfo.satfix = GpsStatus.GPSfix; |
| 85 | GpsStatus.Status = PROCESSED; // never update old data |
||
| 684 | killagreg | 86 | } |
| 702 | killagreg | 87 | if (GpsPosLlh.Status == VALID) // valid packet |
| 684 | killagreg | 88 | { |
| 702 | killagreg | 89 | GPSInfo.longitude = GpsPosLlh.LON; |
| 90 | GPSInfo.latitude = GpsPosLlh.LAT; |
||
| 91 | GPSInfo.altitude = GpsPosLlh.HEIGHT; |
||
| 92 | GpsPosLlh.Status = PROCESSED; // never update old data |
||
| 684 | killagreg | 93 | } |
| 702 | killagreg | 94 | if (GpsPosUtm.Status == VALID) // valid packet |
| 684 | killagreg | 95 | { |
| 702 | killagreg | 96 | GPSInfo.utmeast = GpsPosUtm.EAST; |
| 97 | GPSInfo.utmnorth = GpsPosUtm.NORTH; |
||
| 98 | GPSInfo.utmalt = GpsPosUtm.ALT; |
||
| 99 | GpsPosUtm.Status = PROCESSED; // never update old data |
||
| 684 | killagreg | 100 | } |
| 702 | killagreg | 101 | if (GpsVelNed.Status == VALID) // valid packet |
| 684 | killagreg | 102 | { |
| 702 | killagreg | 103 | GPSInfo.veleast = GpsVelNed.VEL_E; |
| 104 | GPSInfo.velnorth = GpsVelNed.VEL_N; |
||
| 105 | GPSInfo.veltop = -GpsVelNed.VEL_D; |
||
| 106 | GpsPosUtm.Status = PROCESSED; // never update old data |
||
| 684 | killagreg | 107 | } |
| 702 | killagreg | 108 | if (GpsStatus.Status | GpsVelNed.Status | GpsPosLlh.Status | GpsPosUtm.Status) |
| 109 | { |
||
| 110 | GPSInfo.status = VALID; |
||
| 111 | } |
||
| 684 | killagreg | 112 | } |
| 113 | |||
| 114 | // this function should be called within the UART RX ISR |
||
| 115 | void ubx_parser(uint8_t c) |
||
| 116 | { |
||
| 117 | static uint8_t ubxstate = UBXSTATE_IDLE; |
||
| 118 | static uint8_t cka, ckb; |
||
| 119 | static uint16_t msglen; |
||
| 120 | static int8_t *ubxP, *ubxEp, *ubxSp; // pointers to data currently transfered |
||
| 121 | |||
| 122 | switch(ubxstate) |
||
| 123 | { |
||
| 124 | case UBXSTATE_IDLE: // check 1st sync byte |
||
| 125 | if (c == UBX_SYNC1_CHAR) ubxstate = UBXSTATE_SYNC1; |
||
| 126 | else ubxstate = UBXSTATE_IDLE; // out of synchronization |
||
| 127 | break; |
||
| 128 | |||
| 129 | case UBXSTATE_SYNC1: // check 2nd sync byte |
||
| 130 | if (c == UBX_SYNC2_CHAR) ubxstate = UBXSTATE_SYNC2; |
||
| 131 | else ubxstate = UBXSTATE_IDLE; // out of synchronization |
||
| 132 | break; |
||
| 133 | |||
| 134 | case UBXSTATE_SYNC2: // check msg class to be NAV |
||
| 135 | if (c == UBX_CLASS_NAV) ubxstate = UBXSTATE_CLASS; |
||
| 136 | else ubxstate = UBXSTATE_IDLE; // unsupported message class |
||
| 137 | break; |
||
| 138 | |||
| 139 | case UBXSTATE_CLASS: // check message identifier |
||
| 140 | switch(c) |
||
| 141 | { |
||
| 142 | case UBX_ID_POSUTM: // utm position |
||
| 143 | ubxP = (int8_t *)&GpsPosUtm; // data start pointer |
||
| 144 | ubxEp = (int8_t *)(&GpsPosUtm + sizeof(GPS_POSUTM_t)); // data end pointer |
||
| 702 | killagreg | 145 | ubxSp = (int8_t *)&GpsPosUtm.Status; // status pointer |
| 684 | killagreg | 146 | |
| 147 | break; |
||
| 148 | |||
| 149 | case UBX_ID_POSLLH: // geodetic position |
||
| 150 | ubxP = (int8_t *)&GpsStatus; // data start pointer |
||
| 151 | ubxEp = (int8_t *)(&GpsStatus + sizeof(GPS_STATUS_t)); // data end pointer |
||
| 702 | killagreg | 152 | ubxSp = (int8_t *)&GpsStatus.Status; // status pointer |
| 684 | killagreg | 153 | break; |
| 154 | |||
| 155 | case UBX_ID_STATUS: // receiver status |
||
| 156 | ubxP = (int8_t *)&GpsStatus; // data start pointer |
||
| 157 | ubxEp = (int8_t *)(&GpsStatus + sizeof(GPS_STATUS_t)); // data end pointer |
||
| 702 | killagreg | 158 | ubxSp = (int8_t *)&GpsStatus.Status; // status pointer |
| 684 | killagreg | 159 | break; |
| 160 | |||
| 161 | case UBX_ID_VELNED: // velocity vector in tangent plane |
||
| 162 | ubxP = (int8_t *)&GpsVelNed; // data start pointer |
||
| 163 | ubxEp = (int8_t *)(&GpsVelNed + sizeof(GPS_VELNED_t)); // data end pointer |
||
| 702 | killagreg | 164 | ubxSp = (int8_t *)&GpsVelNed.Status; // status pointer |
| 684 | killagreg | 165 | break; |
| 166 | |||
| 167 | default: // unsupported identifier |
||
| 168 | ubxstate = UBXSTATE_IDLE; |
||
| 169 | break; |
||
| 170 | } |
||
| 171 | if (ubxstate != UBXSTATE_IDLE) |
||
| 172 | { |
||
| 173 | ubxstate = UBXSTATE_LEN1; |
||
| 174 | cka = UBX_CLASS_NAV + c; |
||
| 175 | ckb = UBX_CLASS_NAV + cka; |
||
| 176 | } |
||
| 177 | break; |
||
| 178 | |||
| 179 | case UBXSTATE_LEN1: // 1st message length byte |
||
| 180 | msglen = c; |
||
| 181 | cka += c; |
||
| 182 | ckb += cka; |
||
| 183 | ubxstate = UBXSTATE_LEN2; |
||
| 184 | break; |
||
| 185 | |||
| 186 | case UBXSTATE_LEN2: // 2nd message length byte |
||
| 187 | msglen += ((uint16_t)c)<<8; |
||
| 188 | cka += c; |
||
| 189 | ckb += cka; |
||
| 190 | // if the old data are not processed so far then break parsing now |
||
| 191 | // to avoid writing new data in ISR during reading by another function |
||
| 192 | if ( *ubxSp == VALID ) ubxstate = UBXSTATE_IDLE; |
||
| 193 | else // data invalid or allready processd |
||
| 194 | { |
||
| 195 | *ubxSp = INVALID; |
||
| 196 | ubxstate = UBXSTATE_DATA; |
||
| 197 | } |
||
| 198 | break; |
||
| 199 | |||
| 200 | case UBXSTATE_DATA: |
||
| 201 | if (ubxP < ubxEp) *ubxP++ = c; // copy curent data byte if any space is left |
||
| 202 | cka += c; |
||
| 203 | ckb += cka; |
||
| 204 | if (--msglen == 0) ubxstate = UBXSTATE_CKA; // switch to next state if all data was read |
||
| 205 | break; |
||
| 206 | |||
| 207 | case UBXSTATE_CKA: |
||
| 208 | if (c == cka) ubxstate = UBXSTATE_CKB; |
||
| 209 | else ubxstate = UBXSTATE_IDLE; |
||
| 210 | break; |
||
| 211 | |||
| 212 | case UBXSTATE_CKB: |
||
| 213 | if (c == ckb) |
||
| 214 | { |
||
| 215 | *ubxSp = VALID; // new data are availabe |
||
| 216 | UpdateGPSInfo(); //update GPS info respectively |
||
| 702 | killagreg | 217 | ROT_FLASH; |
| 218 | |||
| 684 | killagreg | 219 | } |
| 220 | ubxstate = UBXSTATE_IDLE; // ready to parse new data |
||
| 221 | break; |
||
| 222 | |||
| 223 | default: // unknown ubx state |
||
| 224 | ubxstate = UBXSTATE_IDLE; |
||
| 225 | break; |
||
| 226 | } |
||
| 227 | |||
| 228 | } |
||
| 229 |