BNC 725 - Manual (Page 45)

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Triggering
The triggering options are the same as those for Delayed Pulse After Triggering mode:
Normal
The channel can retrigger an unlimited number of times
Skip N triggers
The channel triggers only after the specified number of input pulses
(between 0 and 2,147,483,647).
Retrigger N times Limits the number of retriggers allowed between resets (between 0
and 2,147,483,647). To allow a channel to be triggered again after
reaching the limit, press the Reset button on the Model 725 or choose
Program > Reset Channels in timerPRO.
Trigger on rising input Sets the channel to be edge triggered. In other words, an input signal
that stays high triggers the channel only once.
Trigger on input high
This option is not used in this mode.
Alert host computer
Sends a “ping” to the PC upon completion of the trigger cycle.
following trigger
The front panel LED for a dynamically-delayed trigger will remain green until a valid input
signal is detected. When an input signal is detected, the LED will glow red until the output signal
is sent. At this point the LED will return to green if retriggering is allowed, or it will glow red to
indicate that no more input signals will be accepted.
To try the dynamically-delayed pulse mode:
You can simulate the experiment above using the external trigger button, connected via BNC to In
1, to represent Sensor 1, and a delayed pulse after trigger in Channel B to represent the signal
from Sensor 2. Connect your oscilloscope to Output C to view the results.
1. On the General Settings screen, select 100/64 (low-resolution) mode for Channels C and D
(and optionally for Channels A and B).
2. Click OK to save the change. A warning may appear listing channels for which the clock
range settings are invalid. Click OK to close the warning. The software will go into “offline”
mode allowing you to adjust the timing settings for the listed channels.
3. On Channel A’s Properties screen select Validated trigger input mode.
4. On Channel A’s Validate tab set the Minimum Duration of Valid Trigger to 10 ms to
debounce the switch. Set the Duration of Pulse to 30 µs.