HP E1432A User's Guide
Using the HP E1432A
Trigger Level
To set the trigger level, use hpe1432_setTriggerMode to select “level” or “bound” mode; and use hpe1432_setTriggerLevel twice to set both the upper and lower trigger levels. The difference between the upper and lower trigger levels must be at least 10% of full scale (and 10% is usually the best amount).
Also use hpe1432setTriggerSlope to specify a positive or negative trigger slope.
Level mode
If the mode is set to “level” and the trigger slope is positive, then the module triggers when the signal crosses both the upper and lower trigger levels in the positive direction. If the trigger slope is negative, the module triggers when the signal crosses both levels in the negative direction. Setting two trigger levels prevents the module from triggering repeatedly when a noisy signal crosses the trigger level.
Bound mode
If the mode is set to “bound” and the trigger slope is positive, then the module triggers when the signal exits the zone between the upper and lower trigger levels in either direction. If the trigger slope is negative, the module triggers when the signal enters the zone between the upper and lower trigger levels.