Counter PXI-6624 able to read the states of the input?

[alex b.]

Hi,

I have a counter PXI-6624. I also need to read a digital input 0-5V. Can I use a counter's channel to do so, i.e., is this card can also return the state of the channel? Or do I need to buy a digital IO card (ex PXI-6528)?

Thank you

Alexandre Boyer

[Nicholas_B]

Greetings Alex,

The driver support for a counter/timer board such as the NI PCI-6624 only allows this device to perform counter tasks, such as edge counting.  Digital input tasks (supported on devices such as the 6528) are used to take a snapshot of a line (ie read its high or low value), while counter tasks can only detect rising or falling edges.  That being said, it would be possible to determine the state of a digital line using this device, but it would require you to write a software algorithm to perform the "read". 

If you know the default state of the line (all pulled low on this device) you could use the counter functions to detect a rising edge, and then you would know that the line is high.  Conversely, if the line was currently high, you could set up a different task to detect falling edges to know when the line was low. 

Although this is possible, I would suggest using a DIO card to perform these tasks.  Please let me know if you have any additional questions...

Regards,

Nicholas B, National Instruments

[alex b.]

Thanks Nicholas,

I will probably go with a DIO card.