Modbus Output Settings for iSIC-V2


The iSIC-V2 Modbus Output tool is designed specifically for applications utilizing a Programmable Logic Controller (PLC) with the Modbus communication protocol (RS-232 or RS-485). Firmware V8.2.023 or higher supports Modbus output. The iSIC V2 acts as a Modbus Master and pushes data to the PLC using the Modbus commands 0x10 (16). Data is pushed at the end of a measurement, and the push frequency is the same as the log interval.

 

Default Modbus Output Communication

Note: The X2 will act as a Modbus Master. 

  • Port: Sensor port RS-485
  • Baud: 19200
  • Frame: N81 (no parity, 8 data bit, 1 stop bit)
  • Slave Modbus address: 1
  • Slave starting Modbus register: 0

 

Register Mapping

  • Register 0,1: 32-bit unsigned timestamp (epoch since midnight Jan 1st, 1970)
  • Register 2,3: 32-bit IEEE 754 floating point number (big endean) of the first parameter
  • Each subsequent parameter occupies 2 Modbus registers each.

 

Modbus Output Configuration

Modbus output is configured using the iSIC V2 built-in console.

  1. To show the current Modbus output configuration:
    1. show mboutput
  2. To change the Modbus output configuration:
    1. set mboutput <flag> [<port> <baud> <frame>]
      • The only required argument for this command is <flag>, the rest of the arguments are optional.
        • <flag>: 0= disable; 1=enable; -1=set to default
        • <port>: 0=RS485; 1=RS-232 P0; 2=RS-232 P1; 3=RS-232 P2
        • <baud>: 3=9600; 4=19200
        • <frame>: 0=N81; 2=E81