Modbus
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      Plugin: Modbus TCP/IP Slave (GInsModbusServerPlugin)

      The GInsModbusServerPlugin provides a simplified way to set up the Q.station controller as a Modbus slave (server) with fixed holding registers.

      Introduction

      Modbus TCP/IP is a version of the Modbus protocol that communicates over Ethernet networks using the TCP/IP stack. It retains the client/server (master/slave) model, where the client initiates requests and the server responds. Holding registers are 16-bit memory locations used to read or write general-purpose data such as configuration settings, control parameters, or measurement values. 

      Using the Modbus Server Plugin, the Q.station controller can be configured as a Modbus TCP/IP server with fixed holding register addresses, as opposed to the variable addressing used in the native Q.station Modbus TCP/IP implementation.

      Minimum System Requirements

      The minimum system requirements for this plugin are:

      • Q.station 101 / Q.station X
      • Q.station firmware V2.18.3

      Plugin Installation

      General Workflow for Configuring the Plugin

      Activate Controller Plugin Mode

      Before configuring the plugin, activate plugin support in the controller settings using GI.bench (Edit controller > Settings > Plugin mode). Write the updated setting to the controller.

      Configure the Plugin

      1. The plugin is configured through a plugin-specific web interface. To access the interface, open a web browser and enter the following URL: http://[qstation_ip]:8090/GInsModbusServerPlugin, where [qstation_ip] is the IP address of the controller.

      2. Set the proffered port number and protocol to either Modbus TCPIP Class 0 or Modbus TCPIP Class 0 (word swapped). The default port for Modbus TCP/IP is 10000.

      3. In the Variable Mapping section, add the controller variables that should be written to Modbus. Once the holding register is set for the first variable, the register numbers for subsequent variables will be automatically assigned based on the variable type. The default type is 32-bit floating point, which requires two 16-bit holding registers.

      4. Click Save to apply and store the plugin configuration settings.