PCI-232 woes

[shoneill]

I have a somewhat unusual problem,

I'm using a PCI-232/4 card (S/N BBCA36) with Windows 2000, NI-Serial 3.0, VISA 3.5 and LV 6.1.

I have some instruments connected to this (Monochromator, filter wheel, linear stage etc.) and I have found that only very few instruments actually work over the NI card.

Attached to the "normal" 2 COM ports of the PC, I can communicate with ALL Instruments no problem.  On the NI card, only two of the instruments work and one of these works via VISA, the other via the old serial VIs.

Does anyone have any idea what I'm doing wrong?  I'm setting Baud, data bit, stop bit, parity, flow control, termination character (for read AND write) Term. Char enable and I'm flushing all buffers before doing anything with the port.



I've been using 232 comms for years now, but I have the feeling I'm missing something small here.......

Please help

Shane.

Message Edited by shoneill on 05-15-2006 04:12 PM

[gwd]

In what manner do they not work? In particular, are there any error messages/ warnings?

Are you able send a (successful) reset signal to the non-responsive instruments?

[shoneill]

Thanks for the response,

upon re-reading my post, I realise too that there's a lot of information missing for anyone to be able to help me.  Sorry.

The problem I have isn't in establishing communication per se, it's just that the communication seems flaky.  I'll try to be more precise.

I have a monochromator which autobauds when I connect to it.  It has a pre-defined series of characters which need to be sent based on the response of the monochromator.  This works fine on a "normal" COM port (Both over VISA and using the old serial drivers).  On the NI card, I can't get the monochromator into a state where I get any of the proper return characters.  The communication IS taking place, I'm just getting the wrong answers.  I've tried setting termination characters, handshaking and so on, but I just can't get it to work.  Note that exactly the code pictured earlier works on a normal COM port, but not on the NI card.

It's almost like one port is speaking english, and the other american.  They respond to each other, but I think there are some "misunderstandings" there or some small syntax errors.  For the life of me, I can't find out where exactly the problem lies.  I suspect the port may have some default setting which I need to force into another state, but I don't know whichs etting, and also which state it needs.

I also have a micrometer gauge which works on a normal COM port, but ot on the NI card.  Here I simply don't get any response at all.

I've left it for dead at the moment.  I'm going to order a USB-RS-232 converter (4 RS-232) as I've used them in the past and have never had trouble with them.

I think when I find the problem, I'll slap myself on the forehead and do a major Homer "D'OH!".  But honestly, it's a "D'OH!" I'm looking forward to.

Shane.

[gwd]

Much clearer. And sounds very frustrating. Had something similar with a program that ran fine until I installed more memory, at which point it refused to run because there was not enough memory. But I digress.

I have used this card without those particular problems. Just one thought. Maybe it's not software. The PCI card as I recall has RJ connectors and then you need an adapter. Maybe it doesn't  have all the lines that the RS232 on the computer has? This might show up more with older devices.

You can also download RS232 port monitor software that might help troubleshoot (if it's software).

[shoneill]

Yeah, it has RJ-45 like ports, but I'm using the converter cables supplied by NI, so I hope that isn't the problem.

The port monitor software sounds good.  Is there something other than NISpy.  AFAIK, Nispy only logs VISA commands, no?

Not all my drivers run over VISA, some are gool 'ol serial VIs.

I have re-written one as a VISA driver out of frustration last week, but it didn't help.  I also think it's either a hardware problem or some wierd setting which has an unusual default on these ports which I'm simply missing.

Oh well, I guess it's in the bin for the card, I'll order a USB-RS232 replicator.

Thanks for the help

Shane.

[DavidJCrawford]

Shane

Just dipped in here and I have a suggestion for monitoring the serial comms here http://www.sysinternals.com/Utilities/Portmon.html

Haven't used it for a while but I remember it being pretty useful at the time.

David

[shoneill]

Thanks David,

I'll give it a try.

Shane.

[nyc_(is_out_of_here)]

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AFAIK, Nispy only logs VISA commands, no?

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NI-Spy will log even non-VISA commands. I used it recently to see commands I was sending using the ibic.exe

versus what my Visual Basic program was sending. I was not using VISA.