[ <rant> I have complained about NI's atrocious documentation for at least two decades. Perhaps the documentation for programming hardware with LabView is better, but since I despise LV, I don't dig in there. Lots of documentation on hardware specs, how wonderful each unit is, but virtually nothing on how to program with them. </rant> ]
CVI 2017, Win7, Win10.
The two cDAQ modules NI9229 and NI9237 are high speed, 4-channel Analog In modules. The minimum sample rate is 1613 Scans/second. 1613 Scans/sec is not useful to me, when using this module with others in a system. My preference is 20 Scans/sec, but the Analog Input Task will not accept that. So I set the rate at 2000 Scans/sec and interrupt every 100 Scans. The task accepts that.
The question here is regarding 1613 vs 2000: What is going on with these modules? And when I get an interrupt 20 times each second, what is in the input buffer for these modules. What is going on with a mix of slow and high speed modules? I am wondering about setting up two analog input tasks for one cDAQ chassis, one for slow modules, one for fast modules.
As far as I know, these modules work -- I get interrupts, I save a fraction of the buffer contents, etc. I would still like to know what is going on.
If I should post this to a hardware forum, which one? I don't see a CompactDAQ forum.
