esphome-docs/components/modbus.rst

.. _modbus:

Modbus Component
================

.. seo::
    :description: Instructions for setting up Modbus in ESPHome.
    :keywords: Modbus

The Modbus protocol is used by many consumer and industrial devices for communication.
This component allows components in ESPHome to communicate to those devices.
Modbus requires a :ref:`UART Bus <uart>` to communicate.

.. code-block:: yaml

    # Example configuration entry
    uart:
      ...

    modbus:


Configuration variables:
------------------------

- **flow_control_pin** (*Optional*, :ref:`config-pin`): The pin used to switch flow control.
    This is useful for RS485 transeivers that do not have automatic flow control switching,
    like the common MAX485.

- **send_wait_time** (*Optional*, :ref:`time`): Time in milliseconds before a new modbus command is sent if an answer from a previous command is pending. Defaults to 250 ms.
    If multiple modbus devices are attached increasing this value can help avoiding to to overlapping reads.
    When 2 devices are sending a command at the same the the response read from uart can't be assigend to the proper design.
    This value defines the maximumm queuing time for a command before it is send anyways.


See Also
--------

- :ref:`uart`
- :apiref:`modbus/modbus.h`
- :ghedit:`Edit`
Add support for sdm_meter energy devices (#745) Co-authored-by: Jesse Hills <3060199+jesserockz@users.noreply.github.com> 2021-05-31 06:06:23 +02:00			`.. _modbus:`

			`Modbus Component`
			`================`

			`.. seo::`
			`:description: Instructions for setting up Modbus in ESPHome.`
			`:keywords: Modbus`

			`The Modbus protocol is used by many consumer and industrial devices for communication.`
			`This component allows components in ESPHome to communicate to those devices.`
			Modbus requires a :ref:`UART Bus <uart>` to communicate.

			`.. code-block:: yaml`

			`# Example configuration entry`
			`uart:`
			`...`

			`modbus:`


			`Configuration variables:`
			`------------------------`

			- flow_control_pin (Optional, :ref:`config-pin`): The pin used to switch flow control.
Modbus controller docs (#1388) Co-authored-by: Jesse Hills <3060199+jesserockz@users.noreply.github.com> 2021-09-26 22:27:26 +02:00			`This is useful for RS485 transeivers that do not have automatic flow control switching,`
			`like the common MAX485.`

			- send_wait_time (Optional, :ref:`time`): Time in milliseconds before a new modbus command is sent if an answer from a previous command is pending. Defaults to 250 ms.
			`If multiple modbus devices are attached increasing this value can help avoiding to to overlapping reads.`
			`When 2 devices are sending a command at the same the the response read from uart can't be assigend to the proper design.`
			`This value defines the maximumm queuing time for a command before it is send anyways.`

Add support for sdm_meter energy devices (#745) Co-authored-by: Jesse Hills <3060199+jesserockz@users.noreply.github.com> 2021-05-31 06:06:23 +02:00
			`See Also`
			`--------`

			- :ref:`uart`
			- :apiref:`modbus/modbus.h`
			- :ghedit:`Edit`