Speed limitation in simultaneous input-output with MIO-16E-1

[elisa 198]

I am working with PCI-MIO-16E-1. I´m trying to acquire continuously from an analog channel and to generate simultaneously a waveform from an analog output. The AO update clock signal configures the scan clock via PFI5.I think this method is good for clock frecuency(updates/sec.configured in the AO)<50000.If the clock frecuency is higher the analog input does not acquire all the samples that it should(output waveform is fine). I need to work with clock frecuency=1M. The board can operate at this rate.Can anybody help me?

[Sastry V.]

Hi,
Sorry for the delay in the response. From your explanation I think the Analog Input is holding the speed. What I mean is, AI Read is a synchronous function and it does not get released until it gets the number of samples to read. During simultaneous operations, this is a big speed issue.

My suggestion would to be take a look at Cont Ack&Chart (Async) example. Async means asynchronous. How you implement it is use a DAQ occurrence to see if the number of samples to read are available and then only call AI read. Otherwise AI read keeps on waiting until required number of samples to read are available.

This way of implementing Analog Input with Analog Output will significantly improve the speed.

Hope this helps. The examples that I referred to are in
LabVIEW Help>> Find Examples >> DAQ ...

Sincerely,
Sastry V
Applications Engineer
National Instruments