gps_test.c

GPS源码

/*********************************************************************************************
* File：	gps_test.c
* Author:	embest
* Desc：	gps function test source code
* History:	R.X.Huang Program start 2005.08.16
*********************************************************************************************/
#include "2410lib.h"

#define PRINT_UART0
#define MSG_GPRMC	0
#define MSG_GPGGA	1
#define MSG_GPGSA	2
#define MSG_GPGSV	3

/*------------------------------------------------------------------------------------------*/
/*	 								function declare					 				    */
/*------------------------------------------------------------------------------------------*/
void gps_test(void);
char uart_tran(void);
void gps_info(UINT32T nType, UINT8T *pPt);

int f_nUartSelect;

void gps_test(void)
{
    char cInputChar;
    char nStrBuf[200];
	int  set_baud,i = 0;
	uart_change_baud(UART1,9600);
	while(1)
	{
		cInputChar = uart_tran();			
			if (cInputChar == '$') 
			{
				if(i != 0)
				{
					if(!strncmp(nStrBuf,"$GPRMC ", 6))		// Format: $GPRMC,DATA,...,DATA
					{
						nStrBuf[i] = cInputChar;
						gps_info(MSG_GPRMC,&nStrBuf[6]);
					}
				}
				i = 0;
			}
			nStrBuf[i] = cInputChar;
			i++;
	}
}

/* sample GPS info string:
$GPGGA,063741.998,2234.2551,N,11408.0338,E,1,08,00.9,00053.1,M,-2.1,M,,*7B
$GPGSA,A,3,06,16,14,22,25,01,30,20,,,,,01.6,00.9,01.3*0D
$GPGSV,2,1,08,06,26,075,44,16,50,227,47,14,57,097,44,22,17,169,42*73
$GPGSV,2,2,08,25,49,352,45,01,64,006,46,30,13,039,39,20,15,312,34*79
$GPRMC,063741.998,A,2234.2551,N,11408.0338,E,000.0,276.0,150805,002.1,W*7C
*/
/*********************************************************************************************
* name:		gps_info
* func:		report the info read from GPS module
* para:		nType:	input, GPS info type (defined)
			pPt:	input, string info pointer
* ret:		none
* modify:
* comment:		
*********************************************************************************************/
void gps_info(UINT32T nType, UINT8T *pPt)
{
	int i,err,nTime,nDate,nDotNum=0;
	char buf[16];
	
	switch(nType)
	{
	case MSG_GPRMC:
		while(*(pPt+1) != '*')
		{
			i = 0;
			while(*++pPt != ',')
				buf[i++] = *pPt;
			buf[i] = '\0';
			
			nDotNum++;
			switch(nDotNum)
			{
			 case 1:				// 格林威治,063741.998: 6时37分41.998秒
			 	nTime = ((buf[0]-0x30)*10+(buf[1]-0x30))<<16|\
			 			((buf[2]-0x30)*10+(buf[3]-0x30))<<8|\
			 			(buf[4]-0x30)*10+(buf[5]-0x30);
			 	break;
			 case 2:				// 信息有效(A)/无效(V)
			 /*
			 	if(buf[0] != 'A')
			 	{
			 		uart_printf(" InValid Message!");
			 		err =1;
			 	}
			*/
			 	break;
			 case 3:				// 2234.2551,N: 北纬22.342551度
			 	if(!err) uart_printf(" North Latitude: %s",buf);
			 	break;
			 case 5:				// 11408.0338,E: 东经114.080338度
			 	if(!err) uart_printf(" East Longtitude: %s\n",buf);
			 	break;
			 case 9:				// 150805: 2005年8月15日
			 	uart_printf(" 20%c%c-%c%c-%c%c", \
			 	              buf[4],buf[5], \
			 	              buf[2],buf[3], \
			 	              buf[0],buf[1]);
				uart_printf(" %02d:%02d:%02d\n",(nTime>>16)&0xFF,(nTime>>8)&0xFF,(nTime)&0xFF);

			 default:
			 	break;
			}
			
		}
		break;
	case MSG_GPGGA:
		// add your code here
		break;
	case MSG_GPGSA:
		// add your code here
		break;
	case MSG_GPGSV:
		// add your code here
	default:
		break;
	}
}

/*********************************************************************************************
* name:		uart_tran
* func:		Get a character from the uart
* para:		none
* ret:		get a char from uart channel
* modify:
* comment:		
*********************************************************************************************/
char uart_tran(void)
{
	while(1)
	{
		if(rUTRSTAT0 & 0x1)
	    {
			f_nUartSelect = UART0;
			return RdURXH0(); 						// Receive data read
	    }
	    else if(rUTRSTAT1 & 0x1)
	    {
			f_nUartSelect = UART1;
			return	rURXH1; 						// Receive data ready
		}
	}
}