Generate a digital output which is the half frequency of the input

[Westman]

Hi, I am new with DAQ. I would like to get your help.

I have a digital signal input which is generated by an encoder. I would like to generate an output signal in the way that its signal level will change at every raising edge of the input signal so that the frequency is the half of that of the input.

I would like to know how to do that using NI DAQ M 6221 card.

Thanks for your help

[Henrik_Volkers · Accepted solution]

Hardware solutions can be so simple ..... sometimes I prefer a solder iron to wire 😄

Look at the counter section..

I think there is a prescaler/divider for the counter ... and next would be trying to route that output to an PFI

[Westman]

Thanks for your reply although I do not quite understand your solution.

[Henrik_Volkers]

What is shown is a D-FlipFlop ( an eletronic basic logic building block see 7474) wired to a hardware frequency divide by 2 .

If you read through the manual of your card (or the DAQmx counter section) you might find that an equivalent circuit could be activated in your card.

The next step would be to use the advanced DAQmx functions to route that divided signal to another PFI output.

If you explain the main task and why you think you need a divide by 2 function, we maybe can find a solution without 😉

[stilly32]

In addition to Henrik's IC solution, you can achieve a divide by two with the 6221. I'm not sure what API you are using, but here is an example of how to set it up in LabVIEW:

Divide External Clock by Two Using Counter in DAQmx 

Hope this helps,

Andrew S.