[PIC] sim 300 gsm modem interfacing with PIC controller

[dxn]

hi
we are interfacing sim 300 with PIC18f. ,using ccs compiler
if i m sending at commands from microcontroller to modem , it is working perfect. we monitor via hyperterminal.
but if i m checking for 'OK' after each at command, it receives only for 1st at command.
here is my code

void main()
{
char c;
int8 i;


 for(i=0;i<10;i++)
  delay_ms( 1000 );
  while(True)
  {
  
printf("AT");
printf("\r");
     
do
{
c=getc();

if ( c== 'E')
{
   printf("AT");
   delay_ms( 10 );
   printf("\r");
   delay_ms( 10 );
  // c=getc();
}


}while(c != 'K');  





  delay_ms( 1000 );
 
 printf("AT+CMGF=1");
printf("\r");
do
{
c=getc();

if ( c== 'E')
{
   printf("AT");
   delay_ms( 10 );
   printf("\r");
   delay_ms( 10 );
  // c=getc();
}


}while(c != 'K');  


  
   delay_ms( 1000 ); 

 }
}

for 'AT', it is receiving OK and reading 'K'. and execution goes to next step.
but for AT+CMGF=1, it is receiving OK. but controller couldnot read K.
expected output was



controller stuck with this instruction
c=getc();

it is getting OK command. but not reading' K'.
is it the delay problem? may be OK reply coming fast?

we r connecting max323 rx to gsm tx and vice versa, just for monitoring purpose only.

please help us....

 

[milan.rajik]

Use Serial receive interrupt to receive the responses.