Instrument Control (GPIB, Serial, VISA, IVI)

cancel
Showing results for 
Search instead for 
Did you mean: 

Reading the 3458a DMM Status Register

Hi everyone,

I'm using the 3458A DMM with labview to measure DC voltage. I'm performin the MATH PFAIL to check if any reading exceeds the limits. In case that happens I would like to perform a certain function. Now in order to check if the limits were exceeded, I'm trying to read the status register byte and check if bit #1 is set (Hi or Low Limit Exceeded). The problem that I'm facing is that the values are being returned as the weighted sum of all set bits, how can I determine which are set? is there a lookup table or something similar?

Also up tell now the values that I'm getting doesn't make any sense. I'm suspecting that there is a problem with the way I'm trying to read the register, but I've tried both the visa read STB function and sending "STB?" with a visa write and reading the returned value with a visa read, both didn't work as expected.

My VI is below, the TEST subVI is only performing the MATH PFAIL test inside the while loop.

 

Capture1.PNG

 

 

 

Thank you for your help 

0 Kudos
Message 1 of 3
(3,795 Views)

Hello! There is a VISA Read STB Function VI, which returns the status byte. I think that's the one you are looking for.

0 Kudos
Message 2 of 3
(3,763 Views)

Hi mmadl,

 

I tried that and it didn't work. I think i figured the problem though. My vi is running so fast that it can't properly read the byte so I need to slow it down with a delay but I don't want to do that really since I need as much measurements as I can get for my results.

 

thanks for your reply though 🙂

 

0 Kudos
Message 3 of 3
(3,749 Views)