Buffered applications / data transfer limitations

[Mroche]

I need to measure counts for precise time durations, (1 sec, 60 sec, 300 sec). My plan is to setup the counters to measure a pulse width and then provide the pulse via a DIO card for the time duration necessary. I have 12 counters that I need to measure simultaneously and I am using two PXI-6602 cards - six counters per card. The PXI-6602 only has three DMA channels per card, so I cannot setup all six counters as DMA.

Would I have any negative effects if I setup 3 channels DMA and 3 channels interrupt based? I will be receiving counts at a maximum rate of about 6500 counts/second and a minimum rate of 2 or 3 counts/second. I have very tight measurement limits, so the counts need to be accurate.

[Mr.F]

Hi Mroche,

Moving from DMA to interrupts would be a problem if you are reading the current count very often. Regardless of what rate the pulses come in, the amount of data returned from your card would be dependent on how fast you sample that current count. If you just want to know how many pulses occurred over the 1, 60 or 300 seconds period than interrupts should be fine.