Tag Archives: Sysmac Way

Implementing the Omron Host Link Protocol (VB.Net)

Previously we used VB6 (Visual Basic 6) to implement the Omron Host Link Protocol to communicate to our programmable logic controller. (PLC) In part 2 we used Visual Basic for Applications (VBA) to accomplish our host link serial communication. We will now look at using VB.Net to establish and retrieve information in and out of the PLC using host link. (C mode commands)

Hostlink communication protocol is a method developed by Omron for communication to PLC’s and other equipment. This ASCII based protocol is used over RS232 or RS422/RS485. It is a many to one implementation which means that you can communicate with up to 32 devices back to a master. (1:N) This communication on the industrial floor can control PLC’s, Temperature Controllers, Panel Meters, etc.

The Omron CP1H plc will be used with a CP1W-CIF11 (RS485) communication serial link adapter. We will also use a USB-485M Universal Serial Bus to RS485 adapter from automation direct. The video at the end of this post will demonstrate the communications by reading 10 registers form the DM area of the PLC. Continue Reading!

Omron CP1H Numbering Systems and Addressing

The Omron CP1H series of programmable logic controllers has a fixed input and output addressing system. Every PLC has its own way of addressing its inputs and outputs. We will be looking at how the CP1H series of controller addresses its inputs and outputs. Numbering systems used in this controller will also be looked at as well as addressing. Addressing can be direct or indirect. We will look at how this can be accomplished using examples in the CP1H controller. Continue Reading!