GPIB232CV-A internal protocol

[mister]

I need bild a new driver for PLC that has a serial interface and I receave on the serial of the plc from a GPIB232CV-A converter the string "ATN DOWN*RST" I should only receave *RST so why I receave also ATN DOWN ? Which are the character added By the GPIB232CV-A converter at output and at input ? where my I find more documentation about Iee 488.2 and about how it works GPIB232CV-A converter ? thank you !

[DiegoF]

Hi,

In what mode are you using the GPIB-232CV-A?. If have been using this box on D mode and I haven't seen this message.

The main document for this box is the < a href = "http://digital.ni.com/manuals.nsf/webAdvsearch/E212C4F2C7E72C8D86256833005E8F03?OpenDocument&vid=niwc&node=132100_US">GPIB-232CV-A User Manual.

If you describe your setup up I might be able to try it out and reproduce the problem.

DiegoF
National Instruments.

[mister]

I was using D mode with no address an I was on the bus looking at the messages that a Personal Computer and a HP LCD meter exchanges ! Anyway my question was : In the vatious mode and settings which are the string I will see that the GPIB-232CV-A adds on INPUT and OUTPUT ? For example If The other GPIB instrument puts the "Attention" line down and sends "CLS" does the GPIB-232CV-A adds "ATN DOWN at the beginning of the reacived string (ATN DOWN CLS) on my RS232? I already readed the manual You suggested me !

[DiegoF]

Hi,

I tested the system you describe and I couldn't get the same results.

I have a GPIB-232CV-A setup for D mode, no address (listen-only), monitoring the communication between the PC and a instrument.

The PC is doing a ID query, the GPIB-232CV-A returns only the data exchange between the device. There is no information on the bus line states (such as ATN).

Could you check the part number of GPIB-232CV-A? I don't think this behavior was changed between revisions but I'll check.

DiegoF
National Instruments.