T4: Different resolution with single read and streaming

3 posts / 0 new

Wed, 04/18/2018 - 13:26

JEV

I'm using the T4 to stream AIN0 and quadrature channel. This works fine. But I found that the minimum difference

applying a fixed analog signal is 20mV. When I use the single read the minimum difference is 5 mV (like 20 V / 4096Dig).

Is this reasonable?

Thu, 04/19/2018 - 12:15

LabJack Support

Currently in stream mode the

Currently in stream mode the T4 defaults to ResolutionIndex=1 where your resolution is only 10-bit. We have not yet documented this behavior, but you try different values of res index (1-5) and see how fast you can go at the different values. We can get you that info pretty quick too.

Write a value of 1-5 to STREAM_RESOLUTION_INDEX before streaming, or if your software can't do that you can use the RegisterMatrix in Kipling to write that register (you might want to save your configuration using the Power-Up Defaults tab).

Note that the default stream res index of 0 should correspond to automatic like the U3. We will get that updated soon:

https://labjack.com/support/datasheets/u3/operation/stream-mode

Fri, 04/20/2018 - 02:10

JEV

Thank you for the information

Thank you for the information, which make sense to me.

I'll go through it next week. I've also an U3 so I can compare the two Device-Types.

P.S. Good to get support direct from the supplier! I like these Labjack-Stuff. ;-)