sim900 and lpc2368 :basic program to send sms

[joel george]

This is more of an algo that i want to implement...i need help
1)shud i be concerned about the reply i get from the gsm modem?(like OK,ERROR...)
2)how shud i den implement it...?

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Code C - [expand]
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#include <stdio.h>
 
extern unsigned char cmgf[]="AT+CMGF=1";    
 
extern unsigned char cmgs[]="AT+CMGS=\"9952082259\"";  
 
extern unsigned char msg1[]="WELCOME TO GSM\0";
 
extern unsigned char msg2[]="USER HAS CROSSED THE BOUNDARY\0";
 
extern unsigned char msg3[]="I’M IN DANGER\0";
 
extern unsigned char msg4[]="PULSE RATE HAS BEEN INCREASING DRASTICALLY\0";
 
extern unsigned char readall[]="AT+CMGR=\"REC UNREAD\"\r\n";
 
void main()
{
pinsel0 = 0x00000000;        // Enable GPIO on all pins
init_serial();
gsmperform();
 
}
 
void gsmperform()
{
while(!(sendstring("AT\r\n")));         //wait till u receive OK
delaygsm();
sendstring("AT+CNMI=2,1,0,0\r\n");//enable read new message
delaygsm();
 
 
sendstring(cmgf);
txu1(0x0d);                                     // equivalent of 
txu1(0x0a);                                     //   enter key
delaygsm();
sendstring(cmgs);
txu1(0x0d);
txu1(0x0a);  
delaygsm();
if(/* SOS key pressed*/)
{
sendstring(msg3);
txu1(0x0d);
txu1(0x0a);  
}
if(/*output of pulse generator >reference*/)
   {
sendstring(msg4);
txu1(0x0d);
txu1(0x0a);  
   }
if(/* latitude,longitude >reference)
{
sendstring(msg2);
txu1(0x0d);
txu1(0x0a);  
}
}
 
 
void init_serial (void)           /* Initialize Serial Interface       */
{                      
    PINSEL0 &= 0xFFFFFF0F; // Reset P0.2,P0.3 Pin Config
    PINSEL0 |= 0x00000010; // Select P0.2 = TxD(UART0)
    PINSEL0 |= 0x00000040; // Select P0.3 = RxD(UART0)
PINSEL1|=0x00000000;
PINSEL2|=0x00000000;
 
    U1LCR   = 0x00000083;         /* 8 bits, no Parity, 1 Stop bit     */
    U1DLL   = 0x000000C2;         /* 9600 Baud Rate @ 30MHz VPB Clock  */
    U0FDR = 0x67; // Fractional Divider
    U1LCR   = 0x00000003;        /* DLAB = 0         */
 
/* MORE HELP FRON UNCLE*/
VICIntSelect&=0xffffff7f;
    VICVectAddr2=(unsigned int)uart1_irq;
    VICIntEnable|=0x00000080;
    VICVectCntl0= 0x0000002F;/*select a priority slot 4a gvn interrupt*/
 
 
}
 
void txuart1(unsigned char data)     //Transmit a byte of data through UART1
{
       while(!(U1LSR & 0x20));         //Wait until UART1 ready to send character  
 
       U1THR = data;
delay(100); //waiting for the receiver to start working
rxuart1(); 
}
 
 
 
 
unsigned char my_arr[16];//for general purpose//
unsigned char* rxuart1()
{
       
    char* ptr = my_arr;
    while(1)
    {
        while((U1LSR&0x01)!=1);
        {
            *ptr++ = U1RBR;
        }
        if(*(--ptr) == 0x0A)
            break;
    }
    
}
 
 
 
int sendstring(unsigned char *p)//Sends a string of data through UART1
{
        while(1)
        {
           if(*p=='\0')
 break;
           txuart1(*p++);
        }
        if(my_arr==”OK”)
return 1;
return 0; 
}
 
void delaygsm()                           //delay function
{
int i,j;
for(i=0;i<60000;i++)
for(j=0;j<51;j++);
}

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[Batang]

I am not sure I understand your question.

You can streamline your code if your strings have cr/lf escape sequences i.e.

extern unsigned char cmgs[]="AT+CMGS=\"9952082259\"\r\n"; etc etc

You can then remove txu1(0x0d); txu1(0x0a);

You can also send string literals i.e. sendstring("AT+CMGS=\"9952082259\"\r\n");

Cheers