Tektronix waveform trigger index

[MacDroid]

Hi,

When I get waveform data from my Tek scope it is an array of y values, the time of t0, and the dx.

How do I find out the trigger index? (i.e.. the index into the array where trigger occurred.

Regards,

Mac

[crossrulz]

What did you set your trigger position to?  I like my trigger position to be at 10%.  So the 10% time would be your trigger point.  I want to say there is a querry to get the trigger index, but I would have to look it up.

[MacDroid]

So if I understand correctly:

1)      I read the waveform data and (with the samples set to 5M) I get a 5M array of y values

2)      If my horizontal position is set to 50% then index 2.5M is the y value at trigger.

Regards,

Mac

[crossrulz]

That is the understanding I had.  I really need to find my programmer's guide and look up that command to get the trigger index.

[ikonen]

Can't you get that from t0 and dt?  I know on LeCroys t0 is set so that the trigger is time = 0 by definition.  If you want the array index of that point, it's (idx =  -t0 / dt).  It's been a while since I've programmed a tek scope, but I'm pretty sure it worked the same way.  Otherwise what is t0 telling you?  Is it always set to 0?