Problem with GPIB commands (while VISA commands is OK)

[titibena]

Hi,

I have a problem to read Keithley 2002 DMM buffer using GPIB Read if the buffer has more than 290 stored value.  As shown in the VI, there are 2 loops for debugging purpose:

1) Configuration 1a

    1st Loop value = 1; 2nd Loop value = 300 (30*10) 

     --> Data reading from buffer is corrupted at the 292th as shown in Read DMM String indicator at the Front Panel of Read DMM Buffer GPIB.vi

2) Configuration 1b

    1st Loop value = 1; 2nd Loop value = 290

     --> There is no data corruption

3) Configuration 2

    1st Loop value = 2; 2nd Loop value = 200  (20*10)

     --> There is no data corruption

4) I retry configuration 1a) but using VISA cmds (Read DMM Buffer.vi) instead of GPIB Read cmd.  No data corruption.

5) with VISA cmds, I increase the buffer storing value (1st Loop value = 1; 2nd Loop value = 600 (60*10)) and there is still no corruption of data.

Could someone tell me what was wrong with the GPIB commands?

As I can not send more than 3 atached files at a time, so here is the first 3 VIs

- Read DMM Buffer

- Read DMM Buffer GPIB

- Test Read DMM Buffer

Thanks.

[titibena]

Here is the last VIs

- Init_Instrument.vi

[Matt_S.]

Hi Titibena,

Please send a spy captpure of the behavior you're seeing. The following Knowledge Base will show you how to get more information stored in that spy file.

Good NI-Spy Files

When we get that we'll be able to help out a bit more with this issue.

Regards,
Matt S.