We are developing an application that continuously (about 50 traces per sec) reads trace data from an 8546A EMI Receiver. We use an 82357B USB-to-GPIB adapter and the Agilent I/O Libraries v14.2, under a VB.NET application. While this is happening, the Activity LED on the 82357 is flickering. If our app stops talking, the Activity LED stays solidly ON.
However, occasionally during data acquisition, the application "pauses" for reasons we cannot determine. During this pause, the Activity LED on the 82357 is OFF (Ready LED remains ON). There is no description in the manuals of this combination of LEDs, so the question is - what does it actually mean when the Activity LED goes OFF? Does it reflect one of the GPIB control lines?
However, occasionally during data acquisition, the application "pauses" for reasons we cannot determine. During this pause, the Activity LED on the 82357 is OFF (Ready LED remains ON). There is no description in the manuals of this combination of LEDs, so the question is - what does it actually mean when the Activity LED goes OFF? Does it reflect one of the GPIB control lines?
> There is no description in the manuals of this combination of LEDs
Please see page 41 of the User's Guide, the 82357B activity LED is off when 82357B is in an idle state.
http://www.soco.agilent.com/org/hifreq/ ... 089657.pdf
I'd take a look at your code and to see what is happening on the GP-IB. It may be useful to use an IO monitor so you can know what is happening on the bus when this pause happens.
If you don't have an IO monitor I know that Agilent IO Libraries 15.0 comes with an IO Monitor.
http://adn.tm.agilent.com/index.cgi?CONTENT_ID=70964
Just launch the monitor and then run your program. The monitor will allow you to watch the bus and you will be able to see what is happening right before the pause (is a query timing out, is there some unexpected reply, etc.)
How long is this pause? Does the program resume on its own?
Good Luck,