Having problems with certain GPIB commands

Hi everyone,

We are trying to read trace data to GPIB from our Advantest R3265
spectrum analyzer,
but it seems to ignore the GPIB command strings that request data
output.

In order to test this, we are using:
"Simple GPIB Read & Write Using VISA COM Interface"
for visual basic 6 from National Instruments, which can be downloaded
here:
http://sine.ni.com/apps/utf8/niepd_web_display.display_epd4?p_guid=01B1A5BD1014319AE0440003BA7CCD71

The commands that the instrument seems to ignore (from the R3265
printed manual) are: "TBA?" "TAB?" "TAA?" and "TBB?".
These commands request data in Binary or ASCII format from memory A or
memory B.

Is there anything in VISA that could prevent the spectrum analyzer from
correctly receiving these?
Many other commands work just fine, while some commands the instrument
ignores.
Has anyone else experienced similar issues with R3265 spectrum
analyzer?

Thanks!
Best regards,
Tele

 

[Ancient_Hacker]

Several things it could be:

Are you sure the device is in the right state for sending data? Some
devices won't respond if they're in data collection mode.

Timing can be an issue. Try adding a second of delay between the
previous command and the one that fails.

Try fetching the device status before and after you request data.
Maybe it's trying to tell you something.