How to sync 5122 scope with 6552 digital IO?

[HaD]

Hello

I have

PXIe-1062Q ,

5122e digitizer: slot 4

6552 slot: 5.

My application is to transmit an waveform from 6552 to some board with CMOS sensor, and to acuire the output (voltage) with the 5122 and tp transform the output to pixel value.

Typical Pixel rate is 1-10MHz.

The acquisition is continuous, and im triggering the 5122 with a script Marker from 6552.

Everything is working fine, except that there is +-1 pixel sync on the acquisition.

Im not using Tclk, and in the way i built my application (some time acquisition is done without transmition and opposite) this will be difficult for me to start Tclk sync because the transmition loop and acquisitio nloop are separated.

I understand that there is an option to sync the 5122 clock to 6552 clock though the star line, but i I dont know how to do it.

Please help.

[HaD]

When i check on external scope the  1) 5122 sample clock, 2) 6552 start transmition Marker.  I can see that the in every new acquistion the scope sample clock is offset. meaning that there is no any sync between the two.

[JuanCarlos]

HaD,

You are correct, when you start the 6552 and the 5122 they will not have a known relationship between the clocks and you'll get some uncertainty in your measurements. I would recommend to use TClk synchronization with some tweaks: you TClk synchronize the 2 boards and start the both with a software start trigger; on your generation you create a script that after starting waits for a script trigger to actually start generating data; and on your acquisition you setup a reference trigger with 0 pre-trigger samples. With a setup like this you can get the consistent results and maintain you trigger setup.  Let me know if this is on the right track and I can provide some more details.

Hope this helps,

Juan Carlos 

[HaD]

When im defining both instruments to use "Start Trigger" the TClk give me error:

"Error -250037 occured at niTClk Initiate.vi:1"

"None of the sessions are configured as the start trigger master session. niTClk Intiate requires one start trigger master"

[jschwartz]

Hi HaD,

You only need to configure a trigger for the first(master) device. You can see how to do this with niScope EX Multi-Device Configured Acquisition (TClk).vi.  You can find these examples in the Example Finder at Help>>Find Examples, then search for TClk.

[HaD]

Thanks,

Now that works im using Start Trigger from 6552 (first i generate clocks to some image sensor, than im Aquiring images with the scope when i want)

But now there is other problem, the TClk process is not robust. Im outputing the sample clocks from 5122 and 6552, and each time im doing TClking sync i see that the align is different. I must get a robust process (i must always acuire image in the pixel point).

My setup is this:

DigitalIO 6552: SampleRate:10MHz, Source: OnBoardClock, RefClock: PXI_CLK10, Start Trigger (Master), Script (Repeat until scripTrigger1...)

Scope5122: SampleRate: 10MHz, Source: OnBoardClock, RefClock: PXI_CLK10, Start Trigger (Slave)

[jschwartz]

Hi HaD,

It sounds like you are doing the TClk synch multiple times.  You should only have to TClk synchronize one time.  Could you please either post your code or past a screenshot of the TClk part of your code?