Loggers - Device Connections: Modbus

This article covers loggers related to Modbus device connections that were introduced in Ignition version 7.8.X.

Loggers in this article:

• drivers.ModbusDriver2[{DeviceConnectionName}]
  • drivers.modbusDriver2[{DeviceConnectionName}].BasicTransactionProcessor
  • drivers.ModbusDriver2[{DeviceConnectionName}].SocketIODelegate

  • drivers.ModbusDriver2[{DeviceConnectionName}].ReadCoilsRequest

  • drivers.ModbusDriver2[{DeviceConnectionName}].ReadDiscreteInputRequest

  • drivers.ModbusDriver2[{DeviceConnectionName}].ReadHoldingRegistersRequest

  • drivers.ModbusDriver2[{DeviceConnectionName}].ReadInputRegistersRequest

  • drivers.ModbusDriver2[[{DeviceConnectionName}].RequestSchedule

• drivers.ModbusOverTCPDriver[{DeviceConnectionName}]

drivers.ModbusDriver2[{DeviceConnectionName}]

A series of loggers monitoring connection status and Tag subscriptions using the Modbus TCP driver. {DeviceConnectionName} is denoted as the name of the specific Modbus device connection in the Ignition config.

• Shows the output of the connection when it is first established.
  • DEBUG log showing a successful device connection when it is first created, then disabled in the Ignition config:
    

    Acquired connect permit, calling connect(). ... Disconnected -> Connecting ... Releasing connect permit. Connecting -> Connected ... Connected -> Disconnecting ... Disconnecting -> Terminated

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drivers.modbusDriver2[{DeviceConnectionName}].BasicTransactionProcessor

• Provides information about created/deleted Tag subscriptions for a specific Modbus TCP device connection.
  • DEBUG log for created/restarted Tag subscriptions where {count} is denoted as the number of Tags being created/restarted.
    

    Processing transaction with sequence {...} Adding {count} items. … Notifying callback of new subscription state: SubscriptionItem[{count}]

• • TRACE log for an individual Tag subscription that was created/restarted. {...} is the specific Modbus TCP Tag name defined on the provider:
    

    Adding {...} Creating AggregateSubscriptionItem for {...}

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drivers.ModbusDriver2[{DeviceConnectionName}].SocketIODelegate

• Shows additional details regarding the output of the connection when it is first established and also during an active connection.
  • DEBUG log showing a successful device connection when it is first created, then disabled in the Ignition config. Instead of a device name being provided, we are instead shown the specific hostname and port defined in the Modbus device connection in Ignition config:
    

    [hostname=10.10.60.75,port=502] Opening TCP connection... [hostname=10.10.60.75,port=502] TCP connection successfully opened.

• • TRACE log showing data being sent during an active Modbus connection. Will log every few seconds:
    

    [hostname=10.10.60.75,port=502] Sending ByteBuffer [ 00 04 00 00 00 06 00 01 00 00 00 01 ]

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drivers.ModbusDriver2[{DeviceConnectionName}].ReadCoilsRequest

• Monitors the read request and response of coil registers at the rate of a tag's tag group / scan class
  • TRACE log showing a successful read request to a modbus device's coil register. In this example, a single tag is created for coil 1:

    Sending message: [ 0B 71 00 00 00 06 00 01 00 00 00 01 ] Received message: [ 0B 71 00 00 00 04 00 01 01 00 ]

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drivers.ModbusDriver2[{DeviceConnectionName}].ReadDiscreteInputRequest

• Monitors the read request and response of discrete input registers at the rate of a tag's tag group / scan class
  • TRACE log showing a successful read request to a modbus device's discrete input register. In this example, a single tag is created for discrete input 1:

    Sending message: [ 14 BC 00 00 00 06 00 02 00 00 00 01 ] Received message: [ 14 BC 00 00 00 04 00 02 01 00 ]

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drivers.ModbusDriver2[{DeviceConnectionName}].ReadHoldingRegistersRequest

• Monitors the read request and response of holding registers at the rate of a tag's tag group / scan class
  • TRACE log showing a successful read request to a modbus device's holding register. In this example, a single tag is created for holding register 1:

    Sending message: [ 15 6A 00 00 00 06 00 03 00 00 00 01 ] Received message: [ 15 6A 00 00 00 05 00 03 02 00 00 ]

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drivers.ModbusDriver2[{DeviceConnectionName}].ReadInputRegistersRequest

• Monitors the read request and response of input registers at the rate of a tag's tag group / scan class
  • TRACE log showing a successful read request to a modbus device's input register. In this example, a single tag is created for holding register address 1:

    Sending message: [ 15 F7 00 00 00 06 00 04 00 00 00 01 ] Received message: [ 15 F7 00 00 00 05 00 04 02 00 00 ]

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drivers.ModbusDriver2[{DeviceConnectionName}].RequestSchedule

• Provides a count of tag subscriptions being consolidated into a separate count of read requests.
  • DEBUG log successfully providing a count of tag subscriptions being consolidated into a separate count of read requests:
    

    Optimized 4 items into 1 read requests. Created new schedule for 4 items in 0ms. Size of new schedule before optimization: 1 Canceling 0 ScheduledRequests. Adding 1 new ScheduledRequests. CRC match. correct == current (2928945580 == 2928945580). Posting 1 ScheduledRequests.

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drivers.ModbusOverTCPDriver[{DeviceConnectionName}]

A series of loggers monitoring connection status and Tag subscriptions using the Modbus RTU over TCP driver. The sub loggers provided are stuctured exactly the same as drivers.ModbusDriver2[{DeviceConnectionName}] listed above