Frequency in cFP CTR 500

[letreca]

Hi, I'm trying to make a measurement of frequency using cFP CTR 500 module and LV 7.1. But I'm just able to acquire the counting of the pulses and, when I acquire 65535 pulses, it resets the counter. What do I need to do to acquire the frequency using these hardware?

[DavidT]

The CTR-500 module only has 16bit resolution, which means that this is as far as it will increment. You could try to connect your system to behave as a 32bit counter as per this example:
Setup 32bit counter

Or you can also setup your counter as per the following example to reset the counter after every frequency measurement read.
Tutorial:
Frequency Measurement Tutorial
Example:
Frequency Measurement Example

hope this helps

[letreca]

Hi. I used the example and I would like to know if there's another way to acquire the frequency without use two CTR channels (one for the signals and the other to the reference). Thank's

[e-Cash-Money]

Hello letreca,

I think you would be able to use one counter (one for the actual signal you are counting) but you would still have to generate a gate signal to reference that was external to the counter module. As long as you know 1) the length of the gate signal and 2) the number of pulses that occured when the gate signal is high, you should be able to determine the frequency and it doesn't really matter where the gate signal comes from. For example, if you send in a gate signal that you know is high for 1 second and you count 10 pulses on the source signal, than you can calculate that you have measured a frequency of 10 Hz.

Take care,
E.Lee