Utilize unused analog DAQ card inputs on 1180 WHILE reading multiplexed SCXI chassis

[mak90]

I have a PCI6250 (16ch) which is connected to a SCXI chassis loaded with a few 1104c modules, 1125 modules, and some multiplexors.

The 6250 is reading the ai on the scxi via multiplexing.

So at this point the 6250 is using only its a0 input, but i would like to also use the other analog inputs on the 6250.

I cannot create and run two separate tasks with this one 6250 though.

I need a task that reads my entire scxi chassis at its max of about 4ksamples/sec, but also have a task that reads the unused ai on the 6250 at a high rate (50k)

I'd appreciate any tips. Thank you!

[Brad_K]

Hi mak90,

In case you didn't know, you can put channels from the SCXI modules and the PCI-6250 in the same task:

However, it sounds like you have over 100 channels, which are too many to acquire at 50 kS/s. Most SCXI AI modules limit the AI convert clock rate to 333 kS/s, and 333 kS/s / 100 = 3.3 kS/s. (Oh, I see you mentioned that the SCXI chassis max rate is about 4 kS/s.)

I think you need a second DAQ board to do both of these things at the same time.

Brad

[GarPar]

Mak90-

     Here is a link to a KnowledgeBase article that discusses this particular issue in detail.  In general, you should be able to use those unused channels.

     I hope this helps.  Best of luck with your application!