Modbus
Modbus is a serial communication protocol to control PLCs (Programmable logic controller). It currently supports sensors and switches which can be controlled over serial, TCP, and UDP connections.
To add modbus to your installation, add the following to your configuration.yaml file:
For a network connection:
# Example configuration.yaml entry for a TCP connection
modbus:
type: tcp
host: IP_ADDRESS
port: 2020
Configuration variables:
- type (Required): Type of the connection to Modbus. Possible values are:
- tcp: Modbus TCP protocol according to “MODBUS Messaging Implementation Guide version 1.0b” provided by Schneider Automation,
- udp: Modbus TCP form, but using UDP for transport (removes the overheads required for TCP),
- rtuovertcp: Modbus RTU message transmitted with a TCP/IP wrapper and sent over a network instead of serial lines.
- host (Required): The IP address of your Modbus device, eg. 192.168.1.1.
- port (Required): The port for the communication.
- timeout (Optional): Timeout for slave response in seconds. (default: 3)
For a serial connection:
# Example configuration.yaml entry for a serial connection
modbus:
type: serial
method: rtu
port: /dev/ttyUSB0
baudrate: 9600
stopbits: 1
bytesize: 8
parity: N
Configuration variables:
- type (Required): Type of the connection to Modbus.
- method (Required): Method of the connection to Modbus.
- port (Required): The port where your Modbus device is connected to your Home Assistant host.
- baudrate (Required): The speed for the serial connection.
- stopbits (Required): The stopbits for the serial connection.
- bytesize (Required): The bytesize for the serial connection.
- parity (Required): The parity for the serial connection.
- timeout (Optional): Timeout for slave response in seconds. (default: 3)
Services
| Service | Description |
|---|---|
| write_register | Write register. Requires unit, address and value fields. value can be either single value or an array |