//Example code for communicating with SOM1

int idComDev; 		//ID of comm device
struct tagDCB dcb; 	//structure of comm device info
int err; 		//returned error code if unable to write to comm port;
int StringLength; 	//Length of data to be sent (always=2);
bool Relay1,Relay2,Relay3,Relay4; //Status of Relays 1=Operated;
int Deviceaddress; 	//Address of SOM1 as selected by DIP switch on the SOM1
char SentString[5]; 	//Data srtring
char temp_str[20]; 	//String used to set up comm ports
int PortNumber; 	//Number of comm port (ie 1 for comm1, 2 for comm2 etc);
char temp_str2[20]; 	//String used for setting up comm port number

// Open Comm Port
strcpy(temp_str,"COM");
itoa(PortNumber,temp_str2,10);
strcat(temp_str,temp_str2);
idComDev = OpenComm(temp_str, 1024, 128); // Set port to required number and buffers 
if (idComDev < 0)
	{
	//Error handling code
	}
strcat(temp_str,":2400,n,8,1"); //set comm port to 2400 baud, with no parity, 8 data bits, and 1 stop bit

//Build Comm Port structure
err = BuildCommDCB(temp_str, &dcb);
if (err < 0)
	{
	//Error handling code
	CloseComm(idComDev);
	}

err = SetCommState(&dcb);
if (err < 0)
	{
	CommPortOpen=FALSE;
	CloseComm(idComDev);
	}

//Send data to SOM1
StringLength=2;
SentString[0]=i;
SentString[1]=(Relay1*128)+(Relay2*64)+(Relay3*32)+(Relay4*16);
SentString[2]=NULL;
err=WriteComm(idComDev, &SentString,StringLength);        //
if (err <0)
	{
	err=GetCommError( idComDev,NULL);
	}

//Close Comm Port
if (CommPortOpen) CloseComm(idComDev);