GPS parser for GPRMB and GPRMC

[minoenea]

Dear all,
I have problems with the parser of GPS string using PIC32.


Could you help me please?

Do you have an example please?

[minoenea]

include
#include
#include
#include


#pragma config FPLLODIV = DIV_1, FPLLMUL = MUL_20, FPLLIDIV = DIV_2, FWDTEN = OFF, FCKSM = CSECME, FPBDIV = DIV_1
#pragma config OSCIOFNC = ON, POSCMOD = XT, FSOSCEN = ON, FNOSC = PRIPLL
#pragma config CP = OFF, BWP = OFF, PWP = OFF

#define GetSystemClock() (80000000ul)
#define GetPeripheralClock() (GetSystemClock()/(1 << OSCCONbits.PBDIV))
#define GetInstructionClock() (GetSystemClock())
#define buf_new 1024


void SendDataBuffer(const char *buffer, UINT32 size);
UINT32 GetMenuChoice(void);
UINT32 GetDataBuffer(char *buffer, UINT32 max_size);

char gps_string[buf_new];
float lat, lon, lat1, lon1;
int fix, qual, dd, led=0;
char *start_ptr, *end_ptr, *latitude, *longitude, *quality;

void parse(volatile unsigned char *string)
{
printf("%s\n", gps_string);


// LATITUDE
start_ptr=strchr(gps_string,','); //find start of time field
start_ptr=strchr(start_ptr+1,','); //find start of latitude field
latitude = start_ptr+1; //find first character in latitude field
printf ("Latitude starts at gps_string[%d]\n",latitude-gps_string);
end_ptr=strchr(latitude,','); //find end of latitude field
printf ("Latitude ends at gps_string[%d]\n",end_ptr-gps_string-1);
if (latitude-gps_string>=end_ptr-gps_string) //determine if latitude exists
{printf("Latitude not received\n");}
else
{
lat=atof(latitude); //convert to float
printf("Latitude = %f\n",lat);
}
// LATITUDE

// LONGITUDE
start_ptr=strchr(start_ptr+1,',');
start_ptr=strchr(start_ptr+1,',');
longitude = start_ptr+1;
printf ("Longitude starts at gps_string[%d]\n",longitude-gps_string);
end_ptr=strchr(longitude,',');
printf ("Longitude ends at gps_string[%d]\n",end_ptr-gps_string-1);
if (longitude-gps_string>=end_ptr-gps_string)
{printf("Longitude not received\n");}
else
{
lon=atof(longitude);
printf("Longitude = %f\n",lon);
}
// LONGITUDE

// QUALITY
start_ptr=strchr(start_ptr+1,',');
start_ptr=strchr(start_ptr+1,',');
quality = start_ptr+1;
printf ("Quality starts at gps_string[%d]\n",quality-gps_string);
end_ptr=strchr(quality,',');
printf ("Quality ends at gps_string[%d]\n",end_ptr-gps_string-1);
if (quality-gps_string>=end_ptr-gps_string)
{
printf("Quality not received\n");

}
else
{
qual=atoi(quality);
printf("Quality = %d\n",qual);
if (qual==1|qual==2){
printf("Fix acquired\n");

}
else{
printf("Fix not aquired\n");

}
}

}



int main(void)
{
UINT32 menu_choice;
UARTConfigure(UART2, UART_ENABLE_PINS_TX_RX_ONLY);
//UARTSetFifoMode(UART2, UART_INTERRUPT_ON_TX_NOT_FULL | UART_INTERRUPT_ON_RX_NOT_EMPTY);
UARTSetLineControl(UART2, UART_DATA_SIZE_8_BITS | UART_PARITY_NONE | UART_STOP_BITS_1);
UARTSetDataRate(UART2, GetPeripheralClock(), 4800);
UARTEnable(UART2, UART_ENABLE_FLAGS(UART_PERIPHERAL | UART_RX | UART_TX));



while(1)
{
if(gps_string[0]=='$' && gps_string[1]=='G' && gps_string[2]=='P' && gps_string[3]=='G' && gps_string[4]=='G')
parse(gps_string);

}
while(1)
{

UINT32 rx_size;
rx_size = GetDataBuffer(gps_string, 1);
SendDataBuffer(gps_string, rx_size);

}

return -1;
}



// ************************************************** ***************************
// void UARTTxBuffer(char *buffer, UINT32 size)
// ************************************************** ***************************
void SendDataBuffer(char *buffer, UINT32 size)
{
while(size)
{
while(!UARTTransmitterIsReady(UART2))
;

UARTSendDataByte(UART2, *buffer);

buffer++;
size--;
}

while(!UARTTransmissionHasCompleted(UART2))
;
}



// ************************************************** ***************************
// UINT32 GetDataBuffer(char *buffer, UINT32 max_size)
// ************************************************** ***************************
UINT32 GetDataBuffer(char *buffer, UINT32 max_size)
{
UINT32 num_char;

num_char = 0;

while(num_char < max_size)
{
UINT8 character;

while(!UARTReceivedDataIsAvailable(UART2))
;

character = UARTGetDataByte(UART2);

// if(character == '\r')
// break;

*buffer = character;

buffer++;
num_char++;
}

return num_char;
}




Ragazzi questo e' tutto il codice scritto per PIC32

Mi dà questi errori


ource\main.c: In function `parse':
source\main.c:32: warning: implicit declaration of function `strchr'
source\main.c: At top level:
source\main.c:128: error: conflicting types for 'SendDataBuffer'
source\main.c:17: error: previous declaration of 'SendDataBuffer' was here
source\main.c:128: error: conflicting types for 'SendDataBuffer'
source\main.c:17: error: previous declaration of 'SendDataBuffer' was here


non capisco.... sto impazzendo.....aiuttoooooooooooooooooooo

grazie a tutti....

[charudatt]

Could you please show me how to extract the speed component from $GPRMC, its variable lenght......

Thank you.