Here is the GPS module. This NEO-6M GPS module communicate with Arduino with a serial. You can learn more about serial communication in my previous post.
In order to plug the module to the Arduino, it requires a bit of soldering.
So you have 4 wire to plug. Each one is labelled on the GPS with:
VCC: Positive 5 volts
RX: Serial reception
TX: Serial output
GND: Ground
Because I’m using the Arduino Mega, I have several Serial ports already available. I decide to wire the GPS module to the Serial1. I use a code found on Ladyada that I modified to work with my configuration.
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// A simple sketch to read GPS data and parse the $GPRMC string // see http://www.ladyada.net/make/gpsshield for more info #define powerpin 4 #define GPSRATE 9600 //#define GPSRATE 38400 #define BYTE 1 // GPS parser for 406a #define BUFFSIZ 90 // plenty big char buffer[BUFFSIZ]; char *parseptr; char buffidx; uint8_t hour, minute, second, year, month, date; uint32_t latitude, longitude; uint8_t groundspeed, trackangle; char latdir, longdir; char status; void setup() { if (powerpin) { pinMode(powerpin, OUTPUT); } pinMode(13, OUTPUT); Serial.begin(GPSRATE); Serial1.begin(GPSRATE); // prints title with ending line break Serial.println("GPS parser"); digitalWrite(powerpin, LOW); // pull low to turn on! } void loop() { uint32_t tmp; Serial.print("\n\rread: "); readline(); // check if $GPRMC (global positioning fixed data) if (strncmp(buffer, "$GPRMC",6) == 0) { // hhmmss time data parseptr = buffer+7; tmp = parsedecimal(parseptr); hour = tmp / 10000; minute = (tmp / 100) % 100; second = tmp % 100; parseptr = strchr(parseptr, ',') + 1; status = parseptr[0]; parseptr += 2; // grab latitude & long data // latitude latitude = parsedecimal(parseptr); if (latitude != 0) { latitude *= 10000; parseptr = strchr(parseptr, '.')+1; latitude += parsedecimal(parseptr); } parseptr = strchr(parseptr, ',') + 1; // read latitude N/S data if (parseptr[0] != ',') { latdir = parseptr[0]; } //Serial.println(latdir); // longitude parseptr = strchr(parseptr, ',')+1; longitude = parsedecimal(parseptr); if (longitude != 0) { longitude *= 10000; parseptr = strchr(parseptr, '.')+1; longitude += parsedecimal(parseptr); } parseptr = strchr(parseptr, ',')+1; // read longitude E/W data if (parseptr[0] != ',') { longdir = parseptr[0]; } // groundspeed parseptr = strchr(parseptr, ',')+1; groundspeed = parsedecimal(parseptr); // track angle parseptr = strchr(parseptr, ',')+1; trackangle = parsedecimal(parseptr); // date parseptr = strchr(parseptr, ',')+1; tmp = parsedecimal(parseptr); date = tmp / 10000; month = (tmp / 100) % 100; year = tmp % 100; Serial.print("\nTime: "); Serial.print(hour, DEC); Serial.print(':'); Serial.print(minute, DEC); Serial.print(':'); Serial.println(second, DEC); Serial.print("Date: "); Serial.print(month, DEC); Serial.print('/'); Serial.print(date, DEC); Serial.print('/'); Serial.println(year, DEC); Serial.print("Lat: "); if (latdir == 'N') Serial.print('+'); else if (latdir == 'S') Serial.print('-'); Serial.print(latitude/1000000, DEC); Serial.print('\°', BYTE); Serial.print(' '); Serial.print((latitude/10000)%100, DEC); Serial.print('\''); Serial.print(' '); Serial.print((latitude%10000)*6/1000, DEC); Serial.print('.'); Serial.print(((latitude%10000)*6/10)%100, DEC); Serial.println('"'); Serial.print("Long: "); if (longdir == 'E') Serial.print('+'); else if (longdir == 'W') Serial.print('-'); Serial.print(longitude/1000000, DEC); Serial.print('\°', BYTE); Serial.print(' '); Serial.print((longitude/10000)%100, DEC); Serial.print('\''); Serial.print(' '); Serial.print((longitude%10000)*6/1000, DEC); Serial.print('.'); Serial.print(((longitude%10000)*6/10)%100, DEC); Serial.println('"'); } //Serial.println(buffer); } uint32_t parsedecimal(char *str) { uint32_t d = 0; while (str[0] != 0) { if ((str[0] > '9') || (str[0] < '0')) return d; d *= 10; d += str[0] - '0'; str++; } return d; } void readline(void) { char c; buffidx = 0; // start at begninning while (1) { c = Serial1.read(); if (c == -1) continue; Serial.print(c); if (c == '\n') continue; if ((buffidx == BUFFSIZ-1) || (c == '\r')) { buffer[buffidx] = 0; return; } buffer[buffidx++]= c; } } |
Here is an example of the output:
As most of the GPS modules communicate the same way, you should be able to use this guide for any other GPS and arduino.
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