PCI 6220-Two digital lines

[padala]

Hi

 I am trying to create two individual signals; both should be  synchronized with each other.

Signal1: One signal with controllable high time and low time (with DAQmx Create Virtual Channel -CO Pulse Time).

Signal2: Simultaneously I want to generate another signal with a specific time delay from rising edge of the Signal1.

 

By changing the initial delay of Signal2, I am trying to control the time delay between two signals.

Enclosed VI gives how I am doing. I understand the way I am doing generates incorrect timing signals, but I am failing to correctly couple the sequence of two signals.

Enclosed pdf gives what exactly I am talking about.

 The problem is here with the time delay, as I am going to micro second levels , I could not get the correct result.

Any help will be great.

 

Thanks and Regards

Srinivas P

[jschwartz]

Hi Srinivas,

the way you have the two tasks set up, they will start whenever the software allows them to and will not be synchronized.  To synchronize two counter tasks, you need to use an arm start trigger to start them at the same time.  You can see a similar example in the following Developer Zone Example:

Synchronize Two Counters using a Dummy AI and an Arm Start Trigger

I have also modified your example to use the AI dummy task.  What this will do is start the generation at the exact same time, so the initial delay will be from the same starting point.  I hope this is helpful.  Have a great weekend!

[padala]

Hi Jim Schwartz

Thanks for your help.Could able to solve my initial problem.

Thnx