I am just starting out in Visual Basic and I'm trying to get hold of any basic source code that will show me how to communicate with Modbus devices via a serial port. I need some basic code that I can play around with and figure out how it works. If there is anybody out there that can help me it would be greatly appreciated.

 

I would recommend checking out www.automatedsolutions.com. They have a demo version of a modbus driver that you can play with. I have used their Allen-Bradley drivers and have had great success. If you are just starting in VB you probably don't want to get into writing drivers. Also, modbus requires some CRC calculations which are hard to do in Basic. I usually just write a .dll in VC++ to handle that kind of stuff. Timothy P. Heckman Sr. Application Engineer [email protected]

 

And, of course, please submit it to the PLCArchive! www.plcarchive.com (Or just fwd it to me and I will post it....) --Joe Jansen ([email protected])

 

Try this freeware MODBUS server. http://members.tripod.com/~mbserver/ <http://members.tripod.com/~mbserver/> Scot Sutherland Senior Controls Engineer Spire Corporation