Rockwell Automation 1747-PCIS API Software - Open Controller - Manual (Page 132)

Publication 1747-UM002A-US-P - June 2000
6-72 Library of Routines
Return Value:
Considerations:
Supported in the Windows NT API library only.
Example:
HANDLE handle;
intrc;
MSGBUF eosMSG
/* Request an output scan, but don’t wait */
OC_DemandOutputScan(handle, OCNOWAIT);
/* Could have other code here */
/* Wait 1 second for the EOS */
rc = OC_WaitForEosDmdOut(handle, 1000);
switch(rc) {
case SUCCESS: /* got EOS*/
/* reset the EOS_DMDOUT event*/
OC_PollScanner (handle,OCMSG_EOS_DMDOUT,&eosMSG);
/* do logic, etc. sychronized with the I/O scan */
break;
case ERR_OCRESPONSE:/* timed out */
printf(“\nTimed out waiting for EOS\n”);
break;
default;
printf(“\nError!\n”);
break;
}
Name: Value: Description:
SUCCESS 0 demand output EOS message was received
ERR_RESPONSE 10 msTimeout milliseconds elapsed without an EOS
ERR_OCACCESS 2
handle
does not have access to scanner