How to synchronize 2 USB 5133

[alex.]

I may need collect 3 channels data at 100M/S simultaneously with low costing.

Each 5133 has 2 channels, so we need at least 2 5133 for 3 channels.

But is there any way to synchronize 2 5133? Software mehod also can.

Thanks.

[Henrik_Volkers]

The spec tell me that there is no sampleclock out option for the PFI, but a sampleclock in 😉

so here are some options:

Use a external 100MHz  source to sync the sampleclocks of both cards (If your tests show that both cards have a sampleclock difference you can't tolerate)

Read one channel on both cards and use software to sync them.  Depending on your signal this will consume more or less calculation power 😉

Use that channel to generate a trigger on both cards (if your signal allow it)

Use the PFI as a common trigger 

PS: If you are from the 'I void guaranties' fraction you can try to open both 5133 and sync the sampleclocks in hardware (But you should know what you do!!)

Use PXI 😉 

You can have it : cheap, quick&easy, good

Pick two!

Message Edited by Henrik Volkers on 12-14-2009 10:48 AM

[alex.]

Actually I just need to trigger the 2 5133 at sametime(accuracy around 0.1ms). Clock may not need the exactly the same. But if can make, will be bonus :).

The data are random pulse. Each channel's data different from others.

Only the pulse waveform is useful and need collection. And the pulse starting time refer to a 50Hz signal also recorded. So I made a triangle wave input to get it.

I am not sure how to set trigger by detect trigger on 3 channels. And how to start data collection at sametime.

I tried attached vi for trigger by analog, but work for one channel only. 

[alex.]

The 5133 seem support relative time in the wfm info. But when I try it, it always give -5.000E-6.

If the relative time can be used, then we no need channel 4 in demo drawing.