modbus2mqtt - software layer to abstract modbus protocol

Configuration

To start the modbus2mqtt service you will need a configuration.yaml in the data folder.

configuration.yaml

Minimal configuration looks like this:

mqtt:
  base_topic: modbus2mqtt
  server: 'mqtt://localhost'
modbus:
  port: /dev/tty.SLAB_USBtoUART
  baud_rate: 9600
  parity: 'none'
  data_bits: 8
  stop_bits: 1
advanced:
  log_output:
    - console
devices:
  device1:
    modbus_id: 1
    model: xy-md02

Note: devices can be added via mqtt as well, see below.

Running

Start with:

npm start

Enable debug logging with:

DEBUG=1 npm start

(recommended the first time to see whats going on)

Topics

Add a new Modbus device

modbus2mqtt/configure/set

Payload:

id: a unique string for you
modbus_id: the id of your Modbus device
interval: in ms the polling period
model: the model of your device as described in modbus-herdsman-converters

{
    id: 'device1',
    modbus_id: 1,
    interval: 10000,
    model: 'xy-md02',
}

Remove a Modbus device

modbus2mqtt/bridge/config/force_remove

Payload:

id: the id of the device to remove

This payload must be sent as a string not as a JSON object.

Read data of a device

modbus2mqtt/:id

You can subscribe to this topic in order to receive data from the device.

Log

modbus2mqtt/bridge/log

In this topic are sent:

ack of a new connected device

{
  type: 'device_connected', 
  message: {
    friendly_name: 'device1'
  }
}

ack of a force removed device

{ 
  type: 'device_force_removed', 
  message: 'device1'
}

Acknowledgments

This work relies on the awesome modbus-serial library.

This work is inspired from the awesome work of Zigbee2MQTT.

License

modbus2mqtt is fair-code licensed under Apache 2.0 with Commons Clause

psy0rz/modbus2mqtt