hello,
I am looking for developer to create some code to operate 4 relays depending on the SMS message received. I have tried to use the code below with an Uno v3 and a sim900 from Maplin.
I can send AT commands to the sim900 and send and receive sms messages but the code below doesn't appear to do anything, although there are no errors when compiling or uploading.
#include <SoftwareSerial.h>
// EN: String buffer for the GPRS shield message
String msg = String("");
// EN: Set to 1 when the next GPRS shield message will contains the SMS message
int SmsContentFlag = 0;
//control pins of relay.
int relay_a=4;
int relay_b=5;
int relay_c=6;
int relay_d=7;
// EN: Code PIN of the SIM card (if applied)
//String SIM_PIN_CODE = String( "XXXX" );
void setup()
{
Serial.begin(19200); // the GPRS baud rate
// Initialize PINs
pinMode( 4, OUTPUT );
pinMode( 5, OUTPUT );
pinMode( 6, OUTPUT );
pinMode( 7, OUTPUT );
digitalWrite( 4, LOW );
digitalWrite( 5, LOW );
digitalWrite( 6, LOW );
digitalWrite( 7, LOW );
Serial.println( "AT+CMGF=1" );
delay(200);
}
void loop()
{
char SerialInByte;
if(Serial.available())
{
SerialInByte = (unsigned char)Serial.read();
delay(5);
// -------------------------------------------------------------------
// EN: Program also listen to the GPRS shield message.
// -------------------------------------------------------------------
// EN: If the message ends with <CR> then process the message
if( SerialInByte == 13 ){
// EN: Store the char into the message buffer
ProcessGprsMsg();
}
if( SerialInByte == 10 ){
// EN: Skip Line feed
}
else {
// EN: store the current character in the message string buffer
msg += String(SerialInByte);
}
}
}
// EN: Make action based on the content of the SMS.
// Notice than SMS content is the result of the processing of several GPRS shield messages.
void ProcessSms( String sms ){
if( sms.indexOf("ona") >= 0 ){
digitalWrite( relay_a, HIGH );
}
if( sms.indexOf("onb") >= 0 ){
digitalWrite( relay_b, HIGH );
}
if( sms.indexOf("onc") >= 0 ){
digitalWrite( relay_c, HIGH );
}
if( sms.indexOf("ond") >= 0 ){
digitalWrite( relay_d, HIGH );
}
if( sms.indexOf("offa") >= 0 ){
digitalWrite( relay_a, LOW );
}
if( sms.indexOf("offb") >= 0 ){
digitalWrite( relay_b, LOW );
}
if( sms.indexOf("offc") >= 0 ){
digitalWrite( relay_c, LOW );
}
if( sms.indexOf("offd") >= 0 ){
digitalWrite( relay_d, LOW );
}
}
// EN: Request Text Mode for SMS messaging
void GprsTextModeSMS(){
Serial.println( "AT+CMGF=1" );
}
void GprsReadSmsStore( String SmsStorePos ){
Serial.print( "AT+CMGR=" );
Serial.println( SmsStorePos );
}
// EN: Clear the GPRS shield message buffer
void ClearGprsMsg(){
msg = "";
}
// EN: interpret the GPRS shield message and act appropiately
void ProcessGprsMsg() {
if( msg.indexOf( "Call Ready" ) >= 0 ){
// Serial.println( "*** GPRS Shield registered on Mobile Network ***" );
GprsTextModeSMS();
}
// EN: unsolicited message received when getting a SMS message
if( msg.indexOf( "+CMTI" ) >= 0 ){
// Serial.println( "*** SMS Received ***" );
// EN: Look for the coma in the full message (+CMTI: "SM",6)
// In the sample, the SMS is stored at position 6
int iPos = msg.indexOf( "," );
String SmsStorePos = msg.substring( iPos+1 );
// Serial.print( "SMS stored at " );
// Serial.println( SmsStorePos );
// EN: Ask to read the SMS store
GprsReadSmsStore( SmsStorePos );
}
// EN: SMS store readed through UART (result of GprsReadSmsStore request)
if( msg.indexOf( "+CMGR:" ) >= 0 ){
// EN: Next message will contains the BODY of SMS
SmsContentFlag = 1;
// EN: Following lines are essentiel to not clear the flag!
ClearGprsMsg();
return;
}
// EN: +CMGR message just before indicate that the following GRPS Shield message
// (this message) will contains the SMS body
if( SmsContentFlag == 1 ){
// Serial.println( "*** SMS MESSAGE CONTENT ***" );
// Serial.println( msg );
// Serial.println( "*** END OF SMS MESSAGE ***" );
ProcessSms( msg );
}
ClearGprsMsg();
// EN: Always clear the flag
SmsContentFlag = 0;
}
happy to pay for the code if people can contact me with prices.
thanks in advance
Dave