I'm developing a modbus master for ENCAL 2000 Gas Chromatograph (GC) using VB6. In the documentation are only functions for read and write into multiple registers. There is no function for establishing the connection between the master and the GC (slave). Would you please be so kind and show me some example (MODBUS message) for master - slave connection.

 

Try google it, I believe it'll give you a lot of results.

 

Hi,

You can download Modbus master VB6 project from http://www.modbus.pl

Regards,
Andrzej

 

Just Go To Modbus.org u will find lot's of resource there for modbus master. also its free to download. Try searching mod101.zip from web. it is the com component for use with vb. zip contains the complete solution for vb developers.

 

You can save yourself significant time and aggrevation by incorporating an off-the-shelf Modbus master ActiveX Control into your VB6 application.

Check out http://www.automatedsolutions.com for a fully functioning Modbus ActiveX Control evaluation version. A powerful pre-built HMI application with VB6 source code is included.

 

There is no "establishing the connection" under Modbus serial or Modbus/TCP. You just start issuing those read/writes. Of course for Modbus/TCP you need to open a TCP/IP socket first, but that is a TCP/IP issue, not Modbus issue.

- LynnL, www.digi.com