How do I send Hex-encoded commands on the GPIB Bus?

[Jimmy R]

I am trying to write a program to talk to a Watlow F4 series controller through a ICS GPIB to RS232 converter card, model number 4894A. The actual Watlow controller uses the ModBus protocol, which requires me to encode all of my commands in Hex. What I'm trying to do is send a command on the GPIB bus, and then read a response. The command will look something like this: 010300000001840A (In hexadecimal). I would then like to read the response, which will also be coded in hexadecimal. I'm using C/C++, so any examples of how to send hex commands on the GPIB bus to the Watlow controller would be great. Any info, links, etc. would also be greatly appreciated.

[DQN]

Are there anyone working on the same issue that using LabVIEW 7.1 control the temperature ESPEC (WATLOW F4)??> I am a beginner and need some advices and examples. I had successful configure the communication fr PC to the temperature champer by WVsetup and Watview throught serial SRS 232 (note: WVsetup and Watview are the software fr WATLOW). Thank you very much in advance
-------DQN--------

[thehobbs]

A good habit to get in when controlling instruments is to always search the Instrument Driver Network (ni.com/idnet) first. There is a Certified LabVIEW Plug and Play driver available for the Watlow F4 series of controllers:
http://sine.ni.com/apps/we/niid_web_display.download_page?p_id_guid=E3B19B3E9722659CE034080020E74861

Jason Hobbs
Instrument Drivers