Bmag incl gps rettelse
Dependencies: mbed WDT MODSERIAL BME280
NMEA/NMEA.cpp@2:39c4a85dc2a4, 2017-02-23 (annotated)
- Committer:
- MAA
- Date:
- Thu Feb 23 13:01:35 2017 +0000
- Revision:
- 2:39c4a85dc2a4
- Parent:
- 0:b3313c5ffca3
- Child:
- 3:38eabaa92552
DateParsing and UTC parsing now working
Who changed what in which revision?
User | Revision | Line number | New contents of line |
---|---|---|---|
MAA | 0:b3313c5ffca3 | 1 | #include "NMEA.h" |
MAA | 0:b3313c5ffca3 | 2 | |
MAA | 0:b3313c5ffca3 | 3 | //constructor with a MODSERIAL pointer to the GPS comms as argument |
MAA | 0:b3313c5ffca3 | 4 | NMEA::NMEA(){ |
MAA | 0:b3313c5ffca3 | 5 | |
MAA | 0:b3313c5ffca3 | 6 | currentGGAString.resize(128); |
MAA | 0:b3313c5ffca3 | 7 | currentGPRMCString.resize(128); |
MAA | 0:b3313c5ffca3 | 8 | currentUTCFromGPRMC.resize(20); |
MAA | 0:b3313c5ffca3 | 9 | currentDATEFromGPRMC.resize(10); |
MAA | 0:b3313c5ffca3 | 10 | |
MAA | 0:b3313c5ffca3 | 11 | chkSumGps.resize(2); |
MAA | 0:b3313c5ffca3 | 12 | |
MAA | 0:b3313c5ffca3 | 13 | iterationIndex = 0; |
MAA | 0:b3313c5ffca3 | 14 | }; |
MAA | 0:b3313c5ffca3 | 15 | |
MAA | 0:b3313c5ffca3 | 16 | //Returns true if GPS CRC corresponds to calculated CRC, else false. |
MAA | 0:b3313c5ffca3 | 17 | bool NMEA::ValidateData(string cstStr, Serial *debg){ |
MAA | 0:b3313c5ffca3 | 18 | |
MAA | 0:b3313c5ffca3 | 19 | //debg->printf("Starting data validation!\r\n"); |
MAA | 0:b3313c5ffca3 | 20 | |
MAA | 0:b3313c5ffca3 | 21 | //Temporary variables used locally only |
MAA | 0:b3313c5ffca3 | 22 | chkSum = 0; |
MAA | 0:b3313c5ffca3 | 23 | |
MAA | 0:b3313c5ffca3 | 24 | //If for some reason the index is wrong, and the first character is not |
MAA | 0:b3313c5ffca3 | 25 | //the beginning dollar sign of a gps string, return false at once. |
MAA | 0:b3313c5ffca3 | 26 | if(cstStr[0] != '$'){ |
MAA | 0:b3313c5ffca3 | 27 | return false; |
MAA | 0:b3313c5ffca3 | 28 | } |
MAA | 0:b3313c5ffca3 | 29 | //debg->printf("First character of gps string is $\r\n"); |
MAA | 0:b3313c5ffca3 | 30 | |
MAA | 0:b3313c5ffca3 | 31 | iterationIndex = 0; |
MAA | 0:b3313c5ffca3 | 32 | |
MAA | 0:b3313c5ffca3 | 33 | //initializing calculated checksum |
MAA | 0:b3313c5ffca3 | 34 | chkSumGps = " "; |
MAA | 0:b3313c5ffca3 | 35 | |
MAA | 0:b3313c5ffca3 | 36 | //debg->printf("Rx checksum string cleared!\r\n"); |
MAA | 0:b3313c5ffca3 | 37 | |
MAA | 0:b3313c5ffca3 | 38 | //Calculating checksum to verify string integrity |
MAA | 0:b3313c5ffca3 | 39 | for(char i = 1; i < cstStr.size(); i++){ |
MAA | 0:b3313c5ffca3 | 40 | //If at end of line for crc check, break |
MAA | 0:b3313c5ffca3 | 41 | if(cstStr[i] == '*' || cstStr[i] == '\0'){ |
MAA | 0:b3313c5ffca3 | 42 | iterationIndex = i; |
MAA | 0:b3313c5ffca3 | 43 | break; |
MAA | 0:b3313c5ffca3 | 44 | } |
MAA | 0:b3313c5ffca3 | 45 | //XOR crc calculation |
MAA | 0:b3313c5ffca3 | 46 | chkSum ^= cstStr[i]; |
MAA | 0:b3313c5ffca3 | 47 | |
MAA | 0:b3313c5ffca3 | 48 | } |
MAA | 0:b3313c5ffca3 | 49 | |
MAA | 0:b3313c5ffca3 | 50 | //debg->printf("The calculated checksum is: %d \r\n", chkSum); |
MAA | 0:b3313c5ffca3 | 51 | |
MAA | 0:b3313c5ffca3 | 52 | //Moving the checksum received into chkSumGps |
MAA | 0:b3313c5ffca3 | 53 | iterationIndex++; |
MAA | 0:b3313c5ffca3 | 54 | chkSumGps[0] = cstStr[iterationIndex]; |
MAA | 0:b3313c5ffca3 | 55 | iterationIndex++; |
MAA | 0:b3313c5ffca3 | 56 | chkSumGps[1] = cstStr[iterationIndex]; |
MAA | 0:b3313c5ffca3 | 57 | |
MAA | 0:b3313c5ffca3 | 58 | GpsCheck = strtol(chkSumGps.c_str(), NULL ,16); |
MAA | 0:b3313c5ffca3 | 59 | |
MAA | 0:b3313c5ffca3 | 60 | //debg->printf("The received checksum is: %d \r\n", GpsCheck); |
MAA | 0:b3313c5ffca3 | 61 | |
MAA | 0:b3313c5ffca3 | 62 | //Verify received and calculated crc equality |
MAA | 0:b3313c5ffca3 | 63 | if(GpsCheck == chkSum){ |
MAA | 0:b3313c5ffca3 | 64 | return true; |
MAA | 0:b3313c5ffca3 | 65 | } |
MAA | 0:b3313c5ffca3 | 66 | |
MAA | 0:b3313c5ffca3 | 67 | //If unequal crc bytes found return false |
MAA | 0:b3313c5ffca3 | 68 | return false; |
MAA | 0:b3313c5ffca3 | 69 | }; |
MAA | 0:b3313c5ffca3 | 70 | |
MAA | 0:b3313c5ffca3 | 71 | |
MAA | 0:b3313c5ffca3 | 72 | //Store function to move GGA to currentGGAString, |
MAA | 0:b3313c5ffca3 | 73 | //or GPRMC to currentGPRMCString |
MAA | 2:39c4a85dc2a4 | 74 | void NMEA::StoreString(string cstStr/*, Serial * debg*/){ |
MAA | 0:b3313c5ffca3 | 75 | static std::string gga = "$GPGGA"; |
MAA | 0:b3313c5ffca3 | 76 | static std::string rmc = "$GPRMC"; |
MAA | 0:b3313c5ffca3 | 77 | |
MAA | 0:b3313c5ffca3 | 78 | //debg->printf("Storing received strings\r\n"); |
MAA | 0:b3313c5ffca3 | 79 | |
MAA | 0:b3313c5ffca3 | 80 | //If received string is a GPGGA string |
MAA | 0:b3313c5ffca3 | 81 | //copy GPGGA string to currentGGAString |
MAA | 0:b3313c5ffca3 | 82 | if(cstStr.compare(0, 6, gga) == 0){ |
MAA | 0:b3313c5ffca3 | 83 | //replace current valid gga string with new valid gga string |
MAA | 0:b3313c5ffca3 | 84 | currentGGAString.replace(0, 128, cstStr); |
MAA | 0:b3313c5ffca3 | 85 | //debg->printf("GGA string replaced with: "); |
MAA | 0:b3313c5ffca3 | 86 | //debg->printf(currentGGAString.c_str()); |
MAA | 0:b3313c5ffca3 | 87 | //debg->printf("\r\n"); |
MAA | 0:b3313c5ffca3 | 88 | } |
MAA | 0:b3313c5ffca3 | 89 | |
MAA | 0:b3313c5ffca3 | 90 | //If received string is a GPRMC string |
MAA | 0:b3313c5ffca3 | 91 | //copy GPRMC string to currentGPRMCString |
MAA | 0:b3313c5ffca3 | 92 | if(cstStr.compare(0, 6, rmc) == 0){ |
MAA | 0:b3313c5ffca3 | 93 | //replace current valid rmc string with new valid rmc string |
MAA | 0:b3313c5ffca3 | 94 | currentGPRMCString.replace(0, 128, cstStr); |
MAA | 0:b3313c5ffca3 | 95 | //debg->printf("GPRMC string replaced with: "); |
MAA | 0:b3313c5ffca3 | 96 | //debg->printf(currentGPRMCString.c_str()); |
MAA | 0:b3313c5ffca3 | 97 | //debg->printf("\r\n"); |
MAA | 0:b3313c5ffca3 | 98 | } |
MAA | 0:b3313c5ffca3 | 99 | |
MAA | 0:b3313c5ffca3 | 100 | }; |
MAA | 0:b3313c5ffca3 | 101 | |
MAA | 0:b3313c5ffca3 | 102 | |
MAA | 0:b3313c5ffca3 | 103 | //Parser / formatter function to get current UTC timestamp from GPRMC |
MAA | 2:39c4a85dc2a4 | 104 | void NMEA::ParseCurrentUTCFromGPRMC(Serial * dbg){ |
MAA | 0:b3313c5ffca3 | 105 | |
MAA | 2:39c4a85dc2a4 | 106 | //getting utc from GPRMC string, assign to tmpStr |
MAA | 2:39c4a85dc2a4 | 107 | getXFromNMEAString(1,currentGPRMCString, dbg); |
MAA | 2:39c4a85dc2a4 | 108 | |
MAA | 2:39c4a85dc2a4 | 109 | currentUTCFromGPRMC = ""; |
MAA | 2:39c4a85dc2a4 | 110 | currentUTCFromGPRMC.resize(20); |
MAA | 2:39c4a85dc2a4 | 111 | |
MAA | 2:39c4a85dc2a4 | 112 | //if time format == 10 characters |
MAA | 2:39c4a85dc2a4 | 113 | if(strlen(tmpStr.c_str()) == 10){ |
MAA | 2:39c4a85dc2a4 | 114 | |
MAA | 2:39c4a85dc2a4 | 115 | //HH |
MAA | 2:39c4a85dc2a4 | 116 | currentUTCFromGPRMC[0] = tmpStr[0]; |
MAA | 2:39c4a85dc2a4 | 117 | currentUTCFromGPRMC[1] = tmpStr[1]; |
MAA | 2:39c4a85dc2a4 | 118 | currentUTCFromGPRMC[2] = ':'; |
MAA | 2:39c4a85dc2a4 | 119 | |
MAA | 2:39c4a85dc2a4 | 120 | //MM |
MAA | 2:39c4a85dc2a4 | 121 | currentUTCFromGPRMC[3] = tmpStr[2]; |
MAA | 2:39c4a85dc2a4 | 122 | currentUTCFromGPRMC[4] = tmpStr[3]; |
MAA | 2:39c4a85dc2a4 | 123 | currentUTCFromGPRMC[5] = ':'; |
MAA | 2:39c4a85dc2a4 | 124 | |
MAA | 2:39c4a85dc2a4 | 125 | //SS |
MAA | 2:39c4a85dc2a4 | 126 | currentUTCFromGPRMC[6] = tmpStr[4]; |
MAA | 2:39c4a85dc2a4 | 127 | currentUTCFromGPRMC[7] = tmpStr[5]; |
MAA | 2:39c4a85dc2a4 | 128 | currentUTCFromGPRMC[8] = '.'; |
MAA | 2:39c4a85dc2a4 | 129 | |
MAA | 2:39c4a85dc2a4 | 130 | //FFF |
MAA | 2:39c4a85dc2a4 | 131 | currentUTCFromGPRMC[9] = tmpStr[7]; |
MAA | 2:39c4a85dc2a4 | 132 | currentUTCFromGPRMC[10] = tmpStr[8]; |
MAA | 2:39c4a85dc2a4 | 133 | currentUTCFromGPRMC[11] = tmpStr[9]; |
MAA | 2:39c4a85dc2a4 | 134 | } |
MAA | 2:39c4a85dc2a4 | 135 | |
MAA | 2:39c4a85dc2a4 | 136 | //if time format == 6 characters |
MAA | 2:39c4a85dc2a4 | 137 | if(strlen(tmpStr.c_str()) == 6){ |
MAA | 2:39c4a85dc2a4 | 138 | |
MAA | 2:39c4a85dc2a4 | 139 | //HH |
MAA | 2:39c4a85dc2a4 | 140 | currentUTCFromGPRMC[0] = tmpStr[0]; |
MAA | 2:39c4a85dc2a4 | 141 | currentUTCFromGPRMC[1] = tmpStr[1]; |
MAA | 2:39c4a85dc2a4 | 142 | currentUTCFromGPRMC[2] = ':'; |
MAA | 2:39c4a85dc2a4 | 143 | |
MAA | 2:39c4a85dc2a4 | 144 | //MM |
MAA | 2:39c4a85dc2a4 | 145 | currentUTCFromGPRMC[3] = tmpStr[2]; |
MAA | 2:39c4a85dc2a4 | 146 | currentUTCFromGPRMC[4] = tmpStr[3]; |
MAA | 2:39c4a85dc2a4 | 147 | currentUTCFromGPRMC[5] = ':'; |
MAA | 2:39c4a85dc2a4 | 148 | |
MAA | 2:39c4a85dc2a4 | 149 | //SS |
MAA | 2:39c4a85dc2a4 | 150 | currentUTCFromGPRMC[6] = tmpStr[4]; |
MAA | 2:39c4a85dc2a4 | 151 | currentUTCFromGPRMC[7] = tmpStr[5]; |
MAA | 2:39c4a85dc2a4 | 152 | currentUTCFromGPRMC[8] = '.'; |
MAA | 2:39c4a85dc2a4 | 153 | |
MAA | 2:39c4a85dc2a4 | 154 | //FFF |
MAA | 2:39c4a85dc2a4 | 155 | currentUTCFromGPRMC[9] = '0'; |
MAA | 2:39c4a85dc2a4 | 156 | currentUTCFromGPRMC[10] = '0'; |
MAA | 2:39c4a85dc2a4 | 157 | currentUTCFromGPRMC[11] = '0'; |
MAA | 2:39c4a85dc2a4 | 158 | } |
MAA | 0:b3313c5ffca3 | 159 | |
MAA | 0:b3313c5ffca3 | 160 | }; |
MAA | 0:b3313c5ffca3 | 161 | |
MAA | 0:b3313c5ffca3 | 162 | //Parser getting current Date from GPRMC |
MAA | 2:39c4a85dc2a4 | 163 | void NMEA::ParseCurrentDateFromGPRMC(Serial * dbg){ |
MAA | 2:39c4a85dc2a4 | 164 | |
MAA | 2:39c4a85dc2a4 | 165 | //Getting date from GPRMC string, assigning to tmpStr |
MAA | 2:39c4a85dc2a4 | 166 | getXFromNMEAString(9,currentGPRMCString, dbg); |
MAA | 0:b3313c5ffca3 | 167 | |
MAA | 2:39c4a85dc2a4 | 168 | currentDATEFromGPRMC = ""; |
MAA | 2:39c4a85dc2a4 | 169 | currentDATEFromGPRMC.resize(20); |
MAA | 2:39c4a85dc2a4 | 170 | |
MAA | 2:39c4a85dc2a4 | 171 | //if date string is the expected length |
MAA | 2:39c4a85dc2a4 | 172 | if(strlen(tmpStr.c_str()) == 6){ |
MAA | 2:39c4a85dc2a4 | 173 | |
MAA | 2:39c4a85dc2a4 | 174 | //Year |
MAA | 2:39c4a85dc2a4 | 175 | currentDATEFromGPRMC[0] = '2'; |
MAA | 2:39c4a85dc2a4 | 176 | currentDATEFromGPRMC[1] = '0'; |
MAA | 2:39c4a85dc2a4 | 177 | currentDATEFromGPRMC[2] = tmpStr[4]; |
MAA | 2:39c4a85dc2a4 | 178 | currentDATEFromGPRMC[3] = tmpStr[5]; |
MAA | 2:39c4a85dc2a4 | 179 | currentDATEFromGPRMC[4] = '/'; |
MAA | 2:39c4a85dc2a4 | 180 | |
MAA | 2:39c4a85dc2a4 | 181 | //Month |
MAA | 2:39c4a85dc2a4 | 182 | currentDATEFromGPRMC[5] = tmpStr[2]; |
MAA | 2:39c4a85dc2a4 | 183 | currentDATEFromGPRMC[6] = tmpStr[3]; |
MAA | 2:39c4a85dc2a4 | 184 | currentDATEFromGPRMC[7] = '/'; |
MAA | 2:39c4a85dc2a4 | 185 | |
MAA | 2:39c4a85dc2a4 | 186 | //Date |
MAA | 2:39c4a85dc2a4 | 187 | currentDATEFromGPRMC[8] = tmpStr[0]; |
MAA | 2:39c4a85dc2a4 | 188 | currentDATEFromGPRMC[9] = tmpStr[1]; |
MAA | 2:39c4a85dc2a4 | 189 | } |
MAA | 2:39c4a85dc2a4 | 190 | |
MAA | 2:39c4a85dc2a4 | 191 | |
MAA | 2:39c4a85dc2a4 | 192 | dbg->printf("currentDATEFromGPRMC: "); |
MAA | 2:39c4a85dc2a4 | 193 | dbg->printf(currentDATEFromGPRMC.c_str()); |
MAA | 2:39c4a85dc2a4 | 194 | dbg->printf("\r\n"); |
MAA | 2:39c4a85dc2a4 | 195 | |
MAA | 0:b3313c5ffca3 | 196 | }; |
MAA | 0:b3313c5ffca3 | 197 | |
MAA | 0:b3313c5ffca3 | 198 | //Verification of gps fix, returns gps fix value character in ascii |
MAA | 2:39c4a85dc2a4 | 199 | bool NMEA::GGAFixVerification(/*Serial * debg*/){ |
MAA | 0:b3313c5ffca3 | 200 | //accessing the string after the sixth comma, which is the gga fix column |
MAA | 2:39c4a85dc2a4 | 201 | //debg->printf("Commencing GGA fix verification\r\n"); |
MAA | 0:b3313c5ffca3 | 202 | |
MAA | 0:b3313c5ffca3 | 203 | char commaCount = 0; |
MAA | 0:b3313c5ffca3 | 204 | char index = 0; |
MAA | 0:b3313c5ffca3 | 205 | |
MAA | 0:b3313c5ffca3 | 206 | while((commaCount < 7) && (currentGGAString[index] != '\0')){ |
MAA | 0:b3313c5ffca3 | 207 | if(currentGGAString[index] == ','){ |
MAA | 0:b3313c5ffca3 | 208 | commaCount += 1; |
MAA | 0:b3313c5ffca3 | 209 | } |
MAA | 0:b3313c5ffca3 | 210 | |
MAA | 0:b3313c5ffca3 | 211 | |
MAA | 0:b3313c5ffca3 | 212 | //if gga fix is 1 or 2, gga fix is sufficient, return true |
MAA | 0:b3313c5ffca3 | 213 | if(commaCount == 6){ |
MAA | 0:b3313c5ffca3 | 214 | if(currentGGAString[index+1] == '1'){ |
MAA | 2:39c4a85dc2a4 | 215 | //debg->printf("Valid GGA fix present(1)!\r\n"); |
MAA | 0:b3313c5ffca3 | 216 | return true; |
MAA | 0:b3313c5ffca3 | 217 | } |
MAA | 0:b3313c5ffca3 | 218 | |
MAA | 0:b3313c5ffca3 | 219 | if(currentGGAString[index+1] == '2'){ |
MAA | 2:39c4a85dc2a4 | 220 | //debg->printf("Valid GGA fix present(2)!\r\n"); |
MAA | 0:b3313c5ffca3 | 221 | return true; |
MAA | 0:b3313c5ffca3 | 222 | } |
MAA | 0:b3313c5ffca3 | 223 | |
MAA | 0:b3313c5ffca3 | 224 | break; |
MAA | 0:b3313c5ffca3 | 225 | } |
MAA | 0:b3313c5ffca3 | 226 | |
MAA | 0:b3313c5ffca3 | 227 | index += 1; |
MAA | 0:b3313c5ffca3 | 228 | |
MAA | 0:b3313c5ffca3 | 229 | } |
MAA | 0:b3313c5ffca3 | 230 | |
MAA | 2:39c4a85dc2a4 | 231 | //debg->printf("Invalid GGA fix!\r\n"); |
MAA | 0:b3313c5ffca3 | 232 | return false; |
MAA | 2:39c4a85dc2a4 | 233 | }; |
MAA | 2:39c4a85dc2a4 | 234 | |
MAA | 2:39c4a85dc2a4 | 235 | void NMEA::getXFromNMEAString(int desiredCommaCount, string stringToParse, Serial * dbg){ |
MAA | 2:39c4a85dc2a4 | 236 | |
MAA | 2:39c4a85dc2a4 | 237 | //clearing tmpStr |
MAA | 2:39c4a85dc2a4 | 238 | tmpStr = ""; |
MAA | 2:39c4a85dc2a4 | 239 | tmpStr.resize(10); |
MAA | 2:39c4a85dc2a4 | 240 | |
MAA | 2:39c4a85dc2a4 | 241 | |
MAA | 2:39c4a85dc2a4 | 242 | int commaCnt = 0; |
MAA | 2:39c4a85dc2a4 | 243 | int index = 0; |
MAA | 2:39c4a85dc2a4 | 244 | int idx = 0; |
MAA | 2:39c4a85dc2a4 | 245 | |
MAA | 2:39c4a85dc2a4 | 246 | while(commaCnt < (desiredCommaCount+1)){ |
MAA | 2:39c4a85dc2a4 | 247 | |
MAA | 2:39c4a85dc2a4 | 248 | if(stringToParse[index] == ','){ |
MAA | 2:39c4a85dc2a4 | 249 | commaCnt += 1; |
MAA | 2:39c4a85dc2a4 | 250 | } |
MAA | 2:39c4a85dc2a4 | 251 | |
MAA | 2:39c4a85dc2a4 | 252 | if((commaCnt == desiredCommaCount) && (stringToParse[index] != ',')){ |
MAA | 2:39c4a85dc2a4 | 253 | tmpStr[idx] = stringToParse[index]; |
MAA | 2:39c4a85dc2a4 | 254 | idx += 1; |
MAA | 2:39c4a85dc2a4 | 255 | } |
MAA | 2:39c4a85dc2a4 | 256 | |
MAA | 2:39c4a85dc2a4 | 257 | index += 1; |
MAA | 2:39c4a85dc2a4 | 258 | } |
MAA | 2:39c4a85dc2a4 | 259 | |
MAA | 2:39c4a85dc2a4 | 260 | dbg->printf("tmpStr: "); |
MAA | 2:39c4a85dc2a4 | 261 | dbg->printf(tmpStr.c_str()); |
MAA | 2:39c4a85dc2a4 | 262 | dbg->printf("\r\n"); |
MAA | 2:39c4a85dc2a4 | 263 | |
MAA | 0:b3313c5ffca3 | 264 | }; |