Synchronizing DAQ boards using RTSI bus

[sergey 671]

Hi!

I have two 6071E boards and would like to synchronize their samplings using the RTSI bus. Does it mean, that their sampling rates must be the same, or I can force the master to sample, say, at 10K and the slave - at 1K ?

A related topic that is unclear: if the clock of a DAQ board works at F Hz, does it always mean that the samplings are performed at F / #channels ? I.e. is the sampling rate defined by the clock or the clock's frequency is permanent and different sampling rates are provided by some frequency divisors between the clock and the digitizer ?

Thank you,
Sergey.

[mikeporter]

The answer to your first question depends on how you define "synchronized". If you are simply having them triggered from the same source, their sample rates can be anything you want. If you want the individual samples to be synchronized, then by definition thye must be running the same sample rate.

The way to tie two boards together is to setup a master/slave configuration where the master routes either its trigger or scan clock to the RTSI bus. The slave then uses that signal to either start its acquisition or clock the acquisition.

In terms of your other questions, the scan clock is how often each channel is sampled. The time between channel samples is defined by the interchannel delay.

There are good examples in LV on how to do this type of acquis
ition.

Mike...