program for a RS232 instrument which connect to GPIB-232

[zqgan]

Hi,

     in our lab , we have an MINOLTA LS110 luminence meter which is connect to the computer through RS232 serial port, and it works well.

     But now, I try to connect the instrument into GPIB-232/485CT-A, and then connect to the computer. In this case, how to write a new driver for the instrument?

     I check the instrument manual, but I can't find any information about the programming.

     Please help me , thank you very much!

[Ebele_Obijiofor]

Hello,

Are you able to communicate with the instrument at all using the GPIB-232/485CT-A? Just to make sure, you are using the RS232 port on your device. correct? In other words, your setup should look something like this: Computer(with GPIB board)<-->GPIB Cable<-->GPIB-232/485CT-A<-->Serial Cable<-->MINOLTA meter.

To communicate with the meter, your GPIB-232/485CT-A should be configured for "G Mode". Is that the configuration you currently have? See the manual for more information on this configuration. Once you have it configured,  you should be able to talk to the meter. 

Unfortunately, as far as writing a new driver for the instrument, I am afraid I can't help much with that.  A few questions though... Does the current driver you have use the NI-VISA API? ( I am assuming it does). If so, you should be able to use the same driver with little or no modifications. If you want to post the driver, I can take a look at it and let you know what I think. Hope this helps. Thanks!

Regards,

Message Edited by _Belle on 04-10-2007 06:32 PM

[zqgan]

Hi,

  Thanks very much for the reply.

  the connection is correct, and the old labview driver is working if the device is conncet to the computer direct with the serial port.

  here is the labview driver. Please help me to make a change.

[Ebele_Obijiofor]

Hello,

Could you please attach the following subVIs as well:

L Serial Port Init.vi
L Serial Port Read.vi

That's where the actual code that talks to the instrument is, and I'll need that to determine what (if any) changes need to be made.  Thanks!

Regards,

[zqgan]

this is the  L serial port init. vi

[zqgan]

this is the L serial port read.

Thank you very much!

[Ebele_Obijiofor]

Hi zqgan,

I am still missing some of the VIs, but I can tell you what you'll need to do to change the VIs you have. You'll have to replace all your "L Serial Port..." VIs with their equivalent VISA VIs from the "Instrument I/O>>VISA" palette. So for instance, you would replace L Serial port read with VISA read.  You can just right-click on the VI you want to change,select replace, and browse to the VISA paletter. Hope this helps. Thanks!

Regards,

Message Edited by _Belle on 04-16-2007 06:26 PM

[zqgan]

Hi,

     Thank you very much!

     I am not familiar with the communication between PC and instrument, so I still need to figure out how to deal with it.

     Anyway, thank you very much!

[Ebele_Obijiofor]

Hi zqgan,

Take a look at the tutorials here and here for some more information on communicating with instruments using VISA. Hope it helps!

Regards,

[zqgan]

Hi,

    after reading these materials, I am still struggling in understanding the connection between GPIB-232 and RS232 instrument.

    after connecting the RS-232 instrument to GPIB-232,  doest the instrument work as a GPIB instrument or RS232 instruments?

    if we take it as a GPIB instruments, How to set the initial parameters such as baut rate, data bit, stop bit, parity bit ? and even the RTS , DTR,CTS,DSR, and the Xoff byte, Xon byte?

    it is really frustrated, please help me.

    Thank you very much!