BNC 725 - Manual (Page 41)

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NOTE: To switch from counter mode, first click the Disable button and ensure the
channel LED is unlit, indicating that the channel is disabled. This will help you avoid
unexpected behaviors when the counter is transmitting measurements rapidly (e.g.,
>1000 measurements per second).
NOTE: When you first run the Model 725, channels that are configured as counters
are initially disabled and must be enabled either by clicking the Enable button on the
channel’s Properties screen, or by using the front panel (See Experimenting:
Disable/Enable Channels below).
The front panel LED for the counter will be green until the first trigger, red until the second
trigger and off while the count data is reported and the channel waits for the input to return low.
The output of a channel in counter mode is always high.
To try the Timer mode:
One good way to see the counter in action is to have it compare the outputs of two clock channels.
The counter will measure the difference between the successive pulses of the two channels.
1. On the General Settings, select 100/64 (low resolution) clock mode.
Channels B and C will be our clocks. We’ll use odd delay and duration values for the clocks
so that the difference between pulses will be obvious.
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 B’s properties screen, select Clock Pulse Stream mode. Enter a High Duration
of 54 ms and a Low Duration of 79 ms. Click Apply.
4. On Channel C’s properties screen, select Clock Pulse Stream mode. Enter a High Duration
of 87 ms and Low Duration of 85 ms. Click Apply.
5. On Channel A’s properties screen select Timer mode.