Communication problems with the Philips PM2525 multimeter

[Jorgen Buelens]

Hello,

I have a problem to communicate with the Philips PM2525 multimeter. I'm rewriting a program that communicates with 4 instruments. In the old version, which was written in DOS, everything works, but under windows the philips multimeter is not being recognized.

My GPIB-PCII/PCIIA board is installed in the PCII mode, IRQ=7 ,and the DMA channel=none. First of all I have upgraded my driver. The ni 488216 was installed. I installed the driver correctly so I went further initialising my GPIB0 card with the following settings :

Primary GPIB adress = 0
Secondary GPIB adress = NONE
Timeout setting = 10s
Terminate read on EOS = NO
Set EOI with EOS on writes = NO
Type of compare on EOS
= 7bit
EOS Byte = 00H
System controller = YES
Assert REN when SC = NO
Enable auto serial polling = YES
Enable CIC protocol = NO
Bus timing = 500ns
Parallel poll duration = DEFAULT

Then I scanned for instruments. First I checked instrument by instrument. Only the multimeter was not recognized. Then I've connected the 3 working instruments after each other and they where all detected. When I connect the multimeter the scan procedure can't find any instruments. If I run the DOS program the multimeter works and communicates correctly.

Can anybody help me with this question.

Thanks,

Jörgen.

[cld]

If the instrumnet is older, there is a good possibility it is not 488.2 compliant. In this case, the scan for instrument will not function properly and could cause this behavior.
Also check the cabeling of the device as well as your compliance to general GPIB setup as listed below:
The limitations for the GPIB bus are identified on pg 730 of our 2001 catalog. They are as follows:
1. A maximum separation of 4m between any two devices and an average seperation of 2m over the entire bus.
2. A maximum total cable length of 20m.
3. No more than 15 device loads connected to each bus, with no less than two-thirds

Note that two GPIB cables can not be connected together to make a longer one without a GPIB device at that junction. Be sure that all cables are connected tightly to
the devices.

Chris D
Applications Engineer
National Instruments