March Madness - GPS Clock

//************************************************************************
//*	GPS Clock
//*		by Mark Sproul
//*		March 6, 2010
//************************************************************************

#include	
#include	
#include	
#include	"WConstants.h"

#include	"wiring.h"


#include	"HardwareSerial.h"
//#include	
#include	



#define	kTX_Pin		4
#define	kRX_Pin		5
#define	kPOWER_Pin	6	//* was 6

#define	kLED1_PIN	7
#define	kLED2_PIN	8

#define kGPSRATE	 4800


//AFSoftSerial gpsSerial		=	AFSoftSerial(kTX_Pin, kRX_Pin);
SoftwareSerial gpsSerial		=	SoftwareSerial(kTX_Pin, kRX_Pin);


#define	kNMEAbuffSize	90		//	plenty big
char		gNMEAbuffer[kNMEAbuffSize];
char		gNMEAbuffidx;
int			gNMEAhour;
int			gNMEAminute;
int			gNMEAsecond;

#define _OUTPUT_TO_CONSOLE_

//************************************************************************
void setup()
{
	Serial.begin(57600);
	Serial.println();
	Serial.println("GPS Clock");

	pinMode(kLED1_PIN, OUTPUT);
	pinMode(kLED1_PIN, OUTPUT);

	//*	turn on the GPS
	pinMode(kPOWER_Pin, OUTPUT);
	digitalWrite(kPOWER_Pin, LOW);		 // pull low to turn on!
	gpsSerial.begin(kGPSRATE);	//*	open GPS port
	Serial.println("GPS Power turned on");
	
	gNMEAbuffidx	=	0;

}




//************************************************************************
//*	$GPGGA,003509.000,4027.4299,N,07430.2057,W,1,04,2.0,40.9,M,-34.1,M,,0000*56
//*	$GPGSA,A,3,32,14,31,30,,,,,,,,,4.0,2.0,3.5*37
//*	$GPRMC,003509.000,A,4027.4299,N,07430.2057,W,0.48,346.15,070310,,*15
//*	$GPGGA,003510.000,4027.4297,N,07430.2055,W,1,04,2.0,40.9,M,-34.1,M,,0000*52
//*	$GPGSA,A,3,32,14,31,30,,,,,,,,,4.0,2.0,3.5*37
//*	$GPGSV,3,1,12,25,70,326,,31,70,008,28,32,51,276,35,01,48,314,26*77
//*	$GPGSV,3,2,12,05,42,054,,14,40,112,22,16,37,195,23,20,28,304,28*70
//*	$GPGSV,3,3,12,30,23,045,28,06,18,074,,07,16,062,,22,09,168,*7D
//*	$GPRMC,003510.000,A,4027.4297,N,07430.2055,W,0.35,144.00,070310,,*1F
//*	$GPGGA,003511.000,4027.4291,N,07430.2051,W,1,04,2.0,40.8,M,-34.1,M,,0000*50
//*	$GPGSA,A,3,32,14,31,30,,,,,,,,,4.0,2.0,3.5*37
//*	$GPRMC,003511.000,A,4027.4291,N,07430.2051,W,1.38,153
//************************************************************************
void ProcessNMEA(char *nmeaBuffer)
{
long	nmeaSentanceType;
long	ii;
char	hourString[4];
char	minString[4];
char	secString[4];


	if ((nmeaBuffer[0] == '$') && (nmeaBuffer[1] == 'G'))
	{
	//	Serial.println(nmeaBuffer);
		nmeaSentanceType	=	0;
		for (ii = 0; ii < 4; ii++)
		{
			nmeaSentanceType	=	nmeaSentanceType <<	8;
			nmeaSentanceType	+=	nmeaBuffer[2 + ii];
		}
	//	Serial.println(nmeaSentanceType, HEX);
		switch(nmeaSentanceType)
		{
		//	case 'PGGA':
			case 0x50474741:
		//		Serial.println(nmeaBuffer);
				ii				=	7;
				hourString[0]	=	nmeaBuffer[ii++];
				hourString[1]	=	nmeaBuffer[ii++];
				hourString[2]	=	0;

				minString[0]	=	nmeaBuffer[ii++];
				minString[1]	=	nmeaBuffer[ii++];
				minString[2]	=	0;

				secString[0]	=	nmeaBuffer[ii++];
				secString[1]	=	nmeaBuffer[ii++];
				secString[2]	=	0;
				Serial.print("\x0c");
				Serial.print(hourString);
				Serial.print(":");
				Serial.print(minString);
				Serial.print(":");
				Serial.print(secString);
				Serial.println(" Zulu");

				gNMEAhour		=	atoi(hourString);
				gNMEAminute		=	atoi(minString);
				gNMEAsecond		=	atoi(secString);
				if (gNMEAsecond == 0)
				{
					Serial.print("\x07");	//*	send a bell
				}
				
				gNMEAhour		+=	19;		//*	adjust to local time

				digitalWrite(kLED1_PIN, HIGH);		//*	turn on LED
				break;
			
		//	case 'PGSV':
			case 0x50475356:
				digitalWrite(kLED1_PIN, LOW);		//*	turn on LED
				break;
		}
	}
}


//************************************************************************
void loop()
{
char	gpsChar;

	gpsChar	=	gpsSerial.read();
	if (gpsChar == 0x0d)
	{
		//*	if its a CR, process the line
		gNMEAbuffer[gNMEAbuffidx++]	=	0;
		ProcessNMEA(gNMEAbuffer);
		gNMEAbuffidx	=	0;
	}
	else if ((gpsChar >= 0x20) && (gNMEAbuffidx < kNMEAbuffSize))
	{
		//*	valid char store it
		gNMEAbuffer[gNMEAbuffidx++]	=	gpsChar;
		
		//*	first char MUST be '$'
		if (gNMEAbuffer[0] != '$')
		{
			gNMEAbuffidx	=	0;
		}
	}

}