pci 6132 retriggerable

[oktanto]

Hi Rohan, Hi Kyle A,

Maybe using DAQmx - Retriggerable AI using Retriggerable Counter could solve on spesified retriggerable AI problems. But when used on my application that I developed, It have many of problems. This is the new problem effect :

1. Digital Trigger sometimes couldn't catch when using retriggerable counter.
2. Start of trigger on acquired signal from AI when we display it, sometimes it can be in start, in the middle, or in the end of sample block. It is varying from time to time on the same measurement.

Spesification of measurement is :

• Measurement single AI (dev1/ai0)
• Sampling frequency 2 MSPS
• Ext Trigger using TTL signal with frequency 1921 Hz, logic low = 0 volt, and logic high = 3.6 volt, dutycycle 50 %

Please suggest what the problems.

Regards,

Oktanto Dedi W

[KrisnaWisnu]

Dear Oktanto,

Can you provide me your input value for samples per channel?

Have you tried the following setup:

1. With Sampling Rate of 2MSPS, External clock to be: 1Hz?

2. With Sampling Rate of 10 SPS, External clock to be 1921 Hz?

While trying the above suggestion, observe these two behaviors:

1. Digital Trigger sometimes couldn't catch when using retriggerable counter.
2. Start of trigger on acquired signal from AI when we display it, sometimes it can be in start, in the middle, or in the end of sample block. It is varying from time to time on the same measurement.

Let me know the results.

[shiwa]

I am using a pci6143 facing the same problem also. Does this card really support the retriggerable function?

[SkyWalka]

The PCI 6132 does have two onboard counter and supports digital triggering, so it is capable of retriggerable tasks (http://www.ni.com/white-paper/5382/en/).  What type of task are you currently trying to make retriggerable?  Here is an example for a retriggerable pulse train:

http://www.ni.com/example/27415/en/

Are you currently using an example?

Are you coding in c/c++ as well?