Honeywell RS-232, Reference Manual

Page: 27 / 152

PC Communication Driver
8/99 RS232 Communications Reference Manual 17
3.2.2 Code sample 1: instantiation of a driver object on the stack
#include “Commbase.h”
#include “Elnapi.h”
void SomeClass::SomeFunction()
{
unsigned char pbyTxMsg[64];
unsigned char pbyRxMsg[64];
int nTxLength;
int nRxLength;
long lRet;
CElnApi CommDriver( “COM2”, // Connect driver to com2.
5000, // 5 sec. timeout.
5, // 5 retries.
2000); // 2 sec. delay between retries.
lRet = CommDriver.SetUpPort( 9600, // 9600 baud.
FALSE, // No parity.
8, // 8 data bits.
1); // 1 stop bit.
if(lRet)
{
// Error handling goes here.
}
sprintf(pbyTxMsg, “My dog has fleas.”)
lRet = CommDriver.OpenPort();
if(lRet)
{
/*
Error handling goes here. Chances are another application has locked
out access to the port.
*/
}
lRet = CommDriver.TransCeive( pbyTxMsg, // Outgoing message ptr.
pbyRxMsg, // Rx buffer.
17, // Outgoing msg length.
64, // Rx buffer size.
&nRxLength, // Actual length of Rx.
1); // Unit addr. 1.
if(lRet)
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