Hello everybody,
I have a Teensy 2, and i want to be able to log the NMEA message from a EM406 GPS
I have take the sketch from http://www.ladyada.net/make/gpsshield/download.html
and i want to use with HardwareSerial Uart for the serial btw gps and teensy
The compilation seem to be good, the teensy run correctly (16 or 8mhz/sdcard), create the log file fine ... but log only ONE sequence in the file, or sometimes, nothing.
If you have any suggestion ...
I have a Teensy 2, and i want to be able to log the NMEA message from a EM406 GPS
I have take the sketch from http://www.ladyada.net/make/gpsshield/download.html
and i want to use with HardwareSerial Uart for the serial btw gps and teensy
The compilation seem to be good, the teensy run correctly (16 or 8mhz/sdcard), create the log file fine ... but log only ONE sequence in the file, or sometimes, nothing.
If you have any suggestion ...
Code:
#include <SD.h>
#include "GPSconfig.h"
const int buttonPin = 17; // Declare PIN 17 for USB mass-storage/charging control
int buttonState = 0; // State button int
// what to log
#define LOG_RMC 1 // RMC-Recommended Minimum Specific GNSS Data, message 103,04
HardwareSerial Uart = HardwareSerial(); // Pin7 Rx Pin8 Tx
// Set the pins used
#define led1Pin 15 // Green LED GPS valid position
#define led2Pin 14 // Red LED Writing data on SDcard
#define pin16 16 // USB and charging mode control
#define chipSelect 0
#define BUFFSIZE 90
char buffer[BUFFSIZE];
uint8_t bufferidx = 0;
bool fix = false;
bool gotGPRMC;
uint8_t i;
File logfile;
// read a Hex value and return the decimal equivalent
uint8_t parseHex(char c) {
if (c < '0')
return 0;
if (c <= '9')
return c - '0';
if (c < 'A')
return 0;
if (c <= 'F')
return (c - 'A')+10;
}
// blink out an error code
void error(uint8_t errno) {
/*
if (SD.errorCode()) {
putstring("SD error: ");
Serial.print(card.errorCode(), HEX);
Serial.print(',');
Serial.println(card.errorData(), HEX);
}
*/
while(1) {
for (i=0; i<errno; i++) {
digitalWrite(led1Pin, HIGH);
delay(100);
digitalWrite(led2Pin, HIGH);
delay(100);
digitalWrite(led1Pin, LOW);
delay(100);
digitalWrite(led2Pin, LOW);
delay(100);
}
for (; i<10; i++) {
delay(200);
}
}
}
void setup() {
pinMode(buttonPin, INPUT_PULLUP); // Set input button pin & pull-up on analog pin 17
//Serial.begin(9600);
//Serial.println("\r\nGPSlogger");
pinMode(led1Pin, OUTPUT);
pinMode(led2Pin, OUTPUT);
// make sure that the default chip select pin is set to
// output, even if you don't use it:
pinMode(0, OUTPUT);
// see if the card is present and can be initialized:
if (!SD.begin(chipSelect)) {
//Serial.println("Card init. failed!");
error(1);
}
strcpy(buffer, "GPSLOG00.LOG");
for (i = 0; i < 100; i++) {
buffer[6] = '0' + i/10;
buffer[7] = '0' + i%10;
// create if does not exist, do not open existing, write, sync after write
if (! SD.exists(buffer)) {
break;
}
}
logfile = SD.open(buffer, FILE_WRITE);
if( ! logfile ) {
//Serial.print("Couldnt create "); Serial.println(buffer);
error(3);
}
//Serial.print("Writing to "); Serial.println(buffer);
//Serial.println("Ready!");
Uart.begin(4800);
delay(250);
#if (LOG_RMC == 1)
Serial.print(RMC_ON);
#else
Serial.print(RMC_OFF);
#endif
delay(250);
}
void loop() {
char c;
uint8_t sum;
buttonState = digitalRead(buttonPin); // Read button state
if (buttonState == LOW) {
digitalWrite(pin16, HIGH); // Enabling charging mode to LTC4054
Serial.begin(9600); // Start serial.begin, open SDCARD to get log
delay(20000);
}
else {
Serial.end(); // Normal mode, disable USB for power saving (4ma off)
}
// read one 'line'
if (Uart.available()) {
c = Uart.read();
#if ARDUINO >= 100
//Serial.write(c);
#else
//Serial.print(c, BYTE);
#endif
if (bufferidx == 0) {
while (c != '$')
c = Uart.read(); // wait till we get a $
}
buffer[bufferidx] = c;
#if ARDUINO >= 100
//Serial.write(c);
#else
//Serial.print(c, BYTE);
#endif
if (c == '\n') {
//putstring_nl("EOL");
//Serial.print(buffer);
buffer[bufferidx+1] = 0; // terminate it
if (buffer[bufferidx-4] != '*') {
// no checksum?
Serial.print('*');
bufferidx = 0;
return;
}
// get checksum
sum = parseHex(buffer[bufferidx-3]) * 16;
sum += parseHex(buffer[bufferidx-2]);
// check checksum
for (i=1; i < (bufferidx-4); i++) {
sum ^= buffer[i];
}
if (sum != 0) {
//putstring_nl("Cxsum mismatch");
//Serial.print('~');
bufferidx = 0;
return;
}
// got good data!
gotGPRMC = strstr(buffer, "GPRMC");
if (strstr(buffer, "GPRMC")) {
// find out if we got a fix
char *p = buffer;
p = strchr(p, ',')+1;
p = strchr(p, ',')+1; // skip to 3rd item
if (p[0] == 'V') {
digitalWrite(led1Pin, LOW);
delay(100);
fix = false;
} else {
digitalWrite(led1Pin, HIGH);
delay(100);
digitalWrite(led1Pin, LOW); // set the LED off
delay(100); // wait for a second
fix = true;
}
}
// rad. lets log it!
//Serial.print(buffer);
//Serial.print('#');
if (gotGPRMC) //If we have a GPRMC string
{
// Bill Greiman - need to write bufferidx + 1 bytes to getCR/LF
bufferidx++;
digitalWrite(led2Pin, HIGH); // sets the digital pin as output
delay(100);
// Bill Greiman - need to write bufferidx + 1 bytes to getCR/LF
logfile.write((uint8_t *) buffer, bufferidx);
logfile.flush();
/*
if( != bufferidx) {
putstring_nl("can't write!");
error(4);
}
*/
digitalWrite(led2Pin, LOW);
bufferidx = 0;
}
return;
}
}
bufferidx++;
if (bufferidx == BUFFSIZE-1) {
Serial.print('!');
bufferidx = 0;
}
}
/* End code */