Simultaneous recording of two digital inputs with PCIe-6323

[Vinayakumar]

Hi,

I have a PCIe-6323 device connected to a connector box (BNC-2120). One of the tasks my PCIe device is configured to do is to use it as a signal counting hardware. The way my signal is currently being read out is the following-- My input signal is a TTL pulse and I apply it to 'USER-DEFINED SIGNALS' port on the BNC-2120 box using a BNC connector. The signal is then applied (using a wire) to BNC-2120 connector's  'Timing I/O' through one of the PFI lines.

Now my issue here is, I need to split this same input signal into two and count them separately using the same hardware. Basically, what I am thinking is to use the second 'USER-DEFINED SIGNALS' port and wire it to one of the remaining PFI lines on the same BNC-2120 connector. 

This way, can my PCIe device be configured to count these two inputs simultaneously, independent of each other?

Happy to give more information, if needed.

Appreciate your time.

Thanks!

Best regards

Vinaya

[Kevin_Price]

It seems odd to split the signal and measure it twice -- unless somehow you have two different programs that need access to the same measurement and you can't combined them into one program.

The approach you described sounds like it ought to work, though I'd probably stick with a single BNC and then route two wire jumper from the User I/O area over to the timing terminals.

-Kevin P

[Vinayakumar]

Thanks, Kevin for the quick reply, it is helpful.

You right -- I do have two different applications that require the same signal to be measured simultaneously and are kind of correlated. Like you suggested, I will try using two wires instead of splitting the signal. 

The number of counters/timers in the datasheet of PCIe-6323 is mentioned to be 4. So, does that mean I can have up to 4 inputs for counting at a time? My requirement is only two inputs (like I mentioned in the first message), but just want to confirm if having more than one input causes any performance issues of the (PCIe) device or is allowed at all. 

Thanks again.

Best regards

Vinaya

[Kevin_Price · Accepted solution]

You should be fine with your X-series device.  The 4 counters are independent so you could do up to 4 counter-based measurements simultaneously without interference or performance issues.   (Multiple tasks with extraordinarily sampling rates in the multi-MHz realm might be an exception, but very very few counter apps call for that.)

-Kevin P

[Vinayakumar]

Thanks again, Kevin for clarifying! This is immensely helpful 🙂 

My sampling rates are usually of the order of 100 kHz.

Appreciate your answer.

Regards

Vinaya