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The ModbusRJ12Device is a component which is responsible for servicing a physical device connected to the ModbusRJ12Network. The device is a Modbus master to all other Modbus devices on the attached RJ12 port. Each device is represented by the ModbusDevice, and has a unique Modbus address (from 1 to 247) as well as the other Modbus config data and starting addresses for Modbus data items (coils, inputs, input registers, holding registers). The component has a Ping action available under the right-click, which sends a test message to the device to check the device status. Each ModbusDevice has a “Ping Address” container slot with 3 properties slots (Address Format, Ping Address Reg, Ping Type). These properties specify a particular data address (either input register or holding register) to use as the device status test (meaning “Monitor” ping requests). Ping requests are generated at the network level by the configurable network monitor (ModbusNetwork -> Ping Enable). When enabled the network monitor periodically pings (queries) this address. If any response is received from the device, including an exception response, this is considered a proof of communication, and the Modbus client device is no longer considered “down” if it had been previously marked “down”.

ModbusRJ12Device component

The ModbusRJ12Device component has the following slots:

  • Status: Device’s actual status (read-only);
    • Available states: OK (device is working properly), Disable (device is disabled, the Enable slot is in false), Down (device is not available), Ok, some points down/error (error in points reading), Network disabled (Modbus network is disabled);
  • Fault Cause: fault cause description;
  • Fault Status: device error status;
    • Available states: true (device communication error), false;
  • Enable: enables/disables the device;
  • IP Address: slave device (gateway) IP address;
  • Device Address: Modbus device address (0 - broadcast, 1-248 addressing range);
  • Timeout: max. device response time from the device request;
  • Inter Message Delay: time between messages sent to the device;
  • Retry Count: max. number of error messages (CRC error, lost messages);
  • Address Format: Modbus address format (Modbus, decimal);
  • Ping Address Reg: any register (Input/Holding) number for device connection test;
  • Ping Type: tested register type: Input/Holding;
  • Byte Order: byte reading order , for32-bit: 3210 (Big endian), 1032 (Little endian).
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