evntqueu c
From Agilent VISA.NET
/* evntqueu.c
This example program illustrates enabling an event queue
using viWaitOnEvent. Note that you must change the address. */
#include <visa.h>
#include <stdio.h>
void main(){
ViSession defaultRM,vi;
ViEventType eventType;
ViEvent eventVi;
ViStatus err;
ViInt16 trigId;
/* open session to VXI device */
viOpenDefaultRM(&defaultRM);
viOpen(defaultRM, "VXI0::24::INSTR", VI_NULL, VI_NULL, &vi);
/* select trigger line TTL0 */
viSetAttribute(vi, VI_ATTR_TRIG_ID, VI_TRIG_TTL0);
/* enable the event */
viEnableEvent(vi, VI_EVENT_TRIG, VI_QUEUE, VI_NULL);
/* fire trigger line, twice */
viAssertTrigger(vi, VI_TRIG_PROT_SYNC);
viAssertTrigger(vi, VI_TRIG_PROT_SYNC);
/* Wait for the event to occur */
err=viWaitOnEvent(vi, VI_EVENT_TRIG, 10000, &eventType, &eventVi);
if(err==VI_ERROR_TMO){
printf("Timeout Occurred! Event not received.\n");
return;
}
/* print the event information */
printf("Trigger Event Occurred!\n");
printf("...Original Device Session = %ld\n", vi);
/* get trigger that fired */
viGetAttribute(eventVi, VI_ATTR_RECV_TRIG_ID, &trigId);
printf("Trigger that fired: ");
switch(trigId){
case VI_TRIG_TTL0:
printf("TTL0");
break;
default:
printf("<other 0x%x>",trigId);
break;
}
printf("\n");
/* close the context before continuing */
viClose(eventVi);
/* get second event */
err=viWaitOnEvent(vi, VI_EVENT_TRIG, 10000, &eventType, &eventVi);
if(err==VI_ERROR_TMO){
printf("Timeout Occurred! Event not received.\n");
return;
}
printf("Got second event\n");
/* close the context before continuing */
viClose(eventVi);
/* unenable event */
viDisableEvent(vi, VI_EVENT_TRIG, VI_QUEUE);
/* close the sessions */
viClose(vi);
viClose(defaultRM);
}