Can't read data for the same lap from two counters

[Kevin_Price]

I'm not familiar with the PXI 5105.  Looking it up, I see it's an scope card and I've never used any of NI's scope devices.  I can't offer any device-specific help.

Are you trying to trigger off the Z index pulse?   If so, you shouldn't have your trigger level set negative.  The Z index is probably a nominal 0-3.3 VDC or 0-5.0 VDC pulse.  I'd look for a negative edge at about a +1.0 VDC level.

If you're triggering off something else entirely where your negative trigger level is appropriate, then I'm afraid I've got nothing much to offer.

-Kevin P

[ArshadAwan]

Hi,

I am triggering scope at a specific voltage level which is negative. Ok thanks a lot.

The problem is same that scope should re-trigger within each lap(Z-index revolution). And scope's callback function is too slow to re trigger the scope to get the next sample.

As you had suggested before I am trying to look  multiple read from scope instead of one.