Connecting PC to a Analysing Instrument

[svu]

Friends,

I've got a assignment in which I need to connect PC to a Analysing Instrument using RS232 cable. Things were pretty fine. I could test the instruments communication with a small program provided by the manufacturer of the system. But, the problem started when i started with my VB module. I'm using traditional MSCOMM activex for communication. My module works excellent with modem but does not work atall with the instrument. It opens the port, sends data. but, nothing comes from the instrument. In one of the manuals they have mentioned the instrument uses DTR/DSR. working for last 7 days and now donno what to do.

you kind help will be highly appreciated.

 

[nigelrivett]

Do you have a data monitor which you can use to monitor the transmissions and find out what is different with your app?

Otherwise get a breakout box which you can use to hold signals.

======================================
Cursors are useful if you don't know sql.
DTS can be used in a similar way.
Beer is not cold and it isn't fizzy.

 

[johnwm]

The MSComm control supports DTR/DSR communications via the DSRHolding Property and the DTREnable Property. The CTS line is also supported via the CTSHolding Property

You'll need to check on your hardware manual to see the required sequence of handshaking to determine how to do it, but normally the computer will ask the modem if it's ready with:
MSComm1.RTSEnable = True
Then wait for the modem to set CTS to True.

You will need to read the manual carefully to see your particular hardware requirements

________________________________________________________________
If you want to get the best response to a question, please check out FAQ222-2244 first

'People who live in windowed environments shouldn't cast pointers.'

 

[svu]

Dear friends,

Thanks to nigelrivett and johnwm for their kind attention. I was working on the same stuff the whole weekend but no luck yet. I do not have a data monitor and frankly no experience with this kind of stuff before. Got info from the internet and tried with my modem. Worked out well. But it did not work with the instrument. To my hard luck the manuals do not mention anything about protocoling. Once place it is just mentioned it uses DTR/DSR. And thats all the info I have. I was searching and found something regarding synchronised and unsynchronised communication. I think this this falls into the later part. But still donno what to do with it.

Your guidance will be of great help to me.

warm regards,
svu