esphome-docs/components/modbus_controller.rst

Modbus Controller
=================

.. seo::
    :description: Instructions for setting up the Modbus Controller component.
    :image: modbus.png

The ``modbus_controller`` component creates a RS485 connection to control a Modbus server (slave) device, letting your ESPHome node to act as a Modbus client (master).
You can access the coils, inputs, holding, read registers from your devices as sensors, switches, selects, numbers or various other ESPHome components and present them to your favorite Home Automation system. You can even write them as binary or float ouptputs from ESPHome.

.. figure:: /images/modbus.png
    :align: center
    :width: 25%

The ``modbus_controller`` component relies on the :doc:`/components/modbus`.



Hardware setup
--------------
You need an RS485 transceiver module:

.. figure:: /images/rs485.jpg

See `How is this RS485 module working? <https://electronics.stackexchange.com/questions/244425/how-is-this-rs485-module-working>`__ on stackexchange for more details.

The transceiver connects to the UART of the MCU. For ESP32, pin ``16`` to ``TXD`` and pin ``17`` to ``RXD`` are the default ones but any other pins can be used as well. ``3.3V`` to ``VCC`` and naturally ``GND`` to ``GND``.

On the bus side, you need 120 Ohm termination resistors at the ends of the bus cable as per Modbus standard. Some transceivers have this already soldered onboard, while some slave devices may have them available via a jumper or a DIP switch.

.. note::

    If you are using an ESP8266, serial logging may cause problems reading from UART. For best results, hardware serial is recommended. Software serial may not be able to read all received data if other components spend a lot of time in the ``loop()``.

    For hardware serial only a limited set of pins can be used. Either ``tx_pin: GPIO1`` and ``rx_pin: GPIO3``  or ``tx_pin: GPIO15`` and ``rx_pin: GPIO13``.

    The disadvantage of using the hardware UART is that you can't use serial logging because the serial logs would be sent to the Modbus device(s) instead, causing errors.

    Serial logging can be disabled by setting ``baud_rate: 0``.

    See :doc:`logger` for more details

    .. code-block:: yaml

        logger:
            level: <level>
            baud_rate: 0

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

- **modbus_id** (*Optional*, :ref:`config-id`): Manually specify the ID of the ``modbus`` hub.

- **address** (**Required**, :ref:`config-id`): The Modbus address of the slave device

- **command_throttle** (*Optional*, :ref:`config-time`): minimum time in between 2 requests to the device. Default is ``0ms``.
  Some Modbus slave devices limit the rate of requests from the master, so this allows the interval between requests to be altered.

- **update_interval** (*Optional*, :ref:`config-time`): The interval that the sensors should be checked.
  Defaults to 60 seconds.

- **offline_skip_updates** (*Optional*, integer): When a slave doesn't respond to a command, it is
  marked as offline, you can specify how many updates will be skipped while it is offline. If using a bus with multiple
  slaves, this avoids waiting for timeouts allowing to read other slaves in the same bus. When the slave
  responds to a command, it'll be marked online again.

Example
-------
The following code creates a ``modbus_controller`` hub talking to a ModBUS device at address ``1`` with ``115200`` bps

ModBUS sensors can be directly defined (inline) under the ``modbus_controller`` hub or as standalone components
Technically there is no difference between the "inline" and the standard definitions approach.

.. code-block:: yaml

    # Example configuration entry
    uart:
      ...

    modbus:
      flow_control_pin: GPIOXX
      id: modbus1

    modbus_controller:
    - id: modbus_device
      address: 0x1   ## address of the Modbus slave device on the bus
      modbus_id: modbus1
      setup_priority: -10

    sensor:
    - platform: modbus_controller
      modbus_controller_id: modbus_device
      name: "Battery Capacity"
      register_type: holding
      address: 0x9001    ## address of the register inside the Modbus slave device
      unit_of_measurement: "AH"
      value_type: U_WORD

    switch:
    - platform: modbus_controller
      modbus_controller_id: modbus_device
      name: "Reset to Factory Default"
      register_type: coil
      address: 0x15
      bitmask: 1

    text_sensor:
    - name: "rtc_clock"
      platform: modbus_controller
      modbus_controller_id: modbus_device
      id: rtc_clock
      internal: true
      register_type: holding
      address: 0x9013
      register_count: 3
      raw_encode: HEXBYTES
      response_size: 6

The configuration example above creates a ``modbus_controller`` hub talking to a Modbus device at address ``1`` with a baudrate of ``115200`` bps, implementing a sensor, a switch and a text sensor.

Check out the various Modbus components available at the bottom of the document in the :ref:`modbusseealso` section. They can be directly defined *(inline)* under the ``modbus_controller`` hub or as standalone components. Technically there is no difference between the *inline* and the standard definitions approach.

Below you find a few general tips about using Modbus in more advanced scenarios. Applicable component functionalities have links pointing here:

.. _bitmasks:

Bitmasks
--------

Some devices use decimal values in read registers to show multiple binary states occupying only one register address. To decode them, you can use bitmasks according to the table below. The decimal value corresponding to a bit is always double of the previous one in the row. Multiple bits can be represented in a single register by making a sum of all the values corresponding to the bits.

+------------+------------------+-----------+-----------+
| Alarm  bit | Description      | DEC value | HEX value |
+============+==================+===========+===========+
| bit 0      | Binary Sensor 0  | 1         | 1         |
+------------+------------------+-----------+-----------+
| bit 1      | Binary Sensor 1  | 2         | 2         |
+------------+------------------+-----------+-----------+
| bit 2      | Binary Sensor 2  | 4         | 4         |
+------------+------------------+-----------+-----------+
| bit 3      | Binary Sensor 3  | 8         | 8         |
+------------+------------------+-----------+-----------+
| bit 4      | Binary Sensor 4  | 16        | 10        |
+------------+------------------+-----------+-----------+
| bit 5      | Binary Sensor 5  | 32        | 20        |
+------------+------------------+-----------+-----------+
| bit 6      | Binary Sensor 6  | 64        | 40        |
+------------+------------------+-----------+-----------+
| bit 7      | Binary Sensor 7  | 128       | 80        |
+------------+------------------+-----------+-----------+
| bit 8      | Binary Sensor 8  | 256       | 100       |
+------------+------------------+-----------+-----------+
| bit 9      | Binary Sensor 9  | 512       | 200       |
+------------+------------------+-----------+-----------+
| bit 10     | Binary Sensor 10 | 1024      | 400       |
+------------+------------------+-----------+-----------+
| bit 11     | Binary Sensor 11 | 2048      | 800       |
+------------+------------------+-----------+-----------+
| bit 12     | Binary Sensor 12 | 4096      | 1000      |
+------------+------------------+-----------+-----------+
| bit 13     | Binary Sensor 13 | 8192      | 2000      |
+------------+------------------+-----------+-----------+
| bit 14     | Binary Sensor 14 | 16384     | 4000      |
+------------+------------------+-----------+-----------+
| bit 15     | Binary Sensor 15 | 32768     | 8000      |
+------------+------------------+-----------+-----------+

In the example below, register ``15``, holds several binary values. It stores the decimal value ``12288``, which is the sum of ``4096`` + ``8192``, meaning the corresponding bits ``12`` and ``13`` are ``1``, the other bits are ``0``.

To gather some of these bits as binary sensors in ESPHome, use ``bitmask``:

.. code-block:: yaml

    binary_sensor:
    - platform: modbus_controller
      modbus_controller_id: modbus1
      name: Alarm bit0
      register_type: read
      address: 15
      bitmask: 0x1
    - platform: modbus_controller
      modbus_controller_id: modbus1
      name: Alarm bit1
      register_type: read
      address: 15
      bitmask: 0x2
    - platform: modbus_controller
      modbus_controller_id: modbus1
      name: Alarm bit10
      register_type: read
      address: 15
      bitmask: 0x400
    - platform: modbus_controller
      modbus_controller_id: modbus1
      name: Alarm bit15
      register_type: read
      address: 15
      bitmask: 0x8000


.. _modbus_custom_command:

Using ``custom_command``
------------------------

``custom_command`` can be used to create an arbitrary modbus command. Combined with a lambda any response can be handled.
This example re-implements the command to read the registers 0x156 (Total active energy) and 0x158 Total (reactive energy) from a SDM-120.
SDM-120 returns the values as floats using 32 bits in 2 registers.

.. code-block:: yaml

    uart:
      id: mod_uart
      ...

    modbus:
      send_wait_time: 200ms
      uart_id: mod_uart
      id: mod_bus

    modbus_controller:
    - id: sdm
      address: 2
      modbus_id: mod_bus
      command_throttle: 100ms
      setup_priority: -10
      update_interval: 30s

    sensors:
    - platform: modbus_controller
      modbus_controller_id: sdm
      name: "Total active energy"
      id: total_energy
      #    address: 0x156
      #    register_type: "read"
      ## reimplement using custom_command
      # 0x2 : modbus device address
      # 0x4 : modbus function code
      # 0x1 : high byte of modbus register address
      # 0x56: low byte of modbus register address
      # 0x00: high byte of total number of registers requested
      # 0x02: low byte of total number of registers requested
      custom_command: [ 0x2, 0x4, 0x1, 0x56,0x00, 0x02]
      value_type: FP32
      unit_of_measurement: kWh
      accuracy_decimals: 1

    - platform: modbus_controller
      modbus_controller_id: sdm
      name: "Total reactive energy"
      #   address: 0x158
      #   register_type: "read"
      custom_command: [0x2, 0x4, 0x1, 0x58, 0x00, 0x02]
      ## the command returns an float value using 4 bytes
      lambda: |-
          ESP_LOGD("Modbus Sensor Lambda","Got new data" );
          union {
            float float_value;
            uint32_t raw;
          } raw_to_float;
          if (data.size() < 4 ) {
            ESP_LOGE("Modbus Sensor Lambda", "invalid data size %d",data.size());
            return NAN;
          }
          raw_to_float.raw =   data[0] << 24 | data[1] << 16 | data[2] << 8 |  data[3];
          ESP_LOGD("Modbus Sensor Lambda", "FP32 = 0x%08X => %f", raw_to_float.raw, raw_to_float.float_value);
          return raw_to_float.float_value;
        unit_of_measurement: kVArh
        accuracy_decimals: 1

.. _modbus_register_count:

Optimizing modbus communications
--------------------------------

``register_count`` is an option only required for uncommon response encodings or to optimizie modbus communications.

It describes the number of registers this data point spans, overriding the defaults determined by ``value_type``. If no value for ``register_count`` is provided, it is calculated based on the register type. The default size for one register is 16 bits (one word). Some devices are not adhering to this convention and have registers larger than 16 bits. In this case, ``register_count`` and  ``response_size`` must be set. For example, if your Modbus device uses one register for a FP32 value (instead of the default of two), set ``register_count: 1`` and ``response_size: 4``.

``register_count`` can also be used to skip a number of registers in consecutive range.

An example is an SDM meter, with interesting data in register addresses 0, 2, 4 and 6:

.. code-block:: yaml

    - platform: modbus_controller
      name: "Voltage Phase 1"
      address: 0
      register_type: "read"
      value_type: FP32

    - platform: modbus_controller
      name: "Voltage Phase 2"
      address: 2
      register_type: "read"
      value_type: FP32

    - platform: modbus_controller
      name: "Voltage Phase 3"
      address: 4
      register_type: "read"
      value_type: FP32

    - platform: modbus_controller
      name: "Current Phase 1"
      address: 6
      register_type: "read"
      value_type: FP32
      accuracy_decimals: 1

The configuration above will generate *one* modbus command *read multiple registers from 0 to 6*.

Maybe you don’t care about the data in register addresses 2 and 4, which are voltage values for Phase 2 and Phase 3 (or you have a SDM-120).
Of course, you can delete the sensors your don’t care about, but then you'd have a gap in the addresses. If you remove the registers at address 2 and 4, *two* commands will be generated -- *read register 0* and *read register 6*. To avoid generating multiple commands and thus reduce activity on the bus, ``register_count`` can be used to fill the gaps:

.. code-block:: yaml

    - platform: modbus_controller
      name: "Voltage Phase 1"
      address: 0
      unit_of_measurement: "V"
      register_type: "read"
      value_type: FP32
      register_count: 6

    - platform: modbus_controller
      name: "Current Phase 1"
      address: 6
      register_type: "read"
      value_type: FP32

Because the option ``register_count: 6`` is used for the first sensor, *one* command *read multiple registers from 0 to 6* will be used but the values in between will be ignored.

.. note:: *Calculation:* FP32 is a 32 bit value and uses 2 registers. Therefore, to skip the 2 FP32 registers the size of these 2 registers must be added to the default size for the first register. So we have 2 for address 0, 2 for address 2 and 2 for address 4 thus ``register_count`` must be 6.


Protocol decoding example
-------------------------

.. code-block:: yaml

    sensors:
    - platform: modbus_controller
      modbus_controller_id: epever
      id: array_rated_voltage
      name: "array_rated_voltage"
      address: 0x3000
      unit_of_measurement: "V"
      register_type: read
      value_type: U_WORD
      accuracy_decimals: 1
      skip_updates: 60
      filters:
        - multiply: 0.01

    - platform: modbus_controller
      modbus_controller_id: epever
      id: array_rated_current
      name: "array_rated_current"
      address: 0x3001
      unit_of_measurement: "V"
      register_type: read
      value_type: U_WORD
      accuracy_decimals: 2
      filters:
        - multiply: 0.01

    - platform: modbus_controller
      modbus_controller_id: epever
      id: array_rated_power
      name: "array_rated_power"
      address: 0x3002
      unit_of_measurement: "W"
      register_type: read
      value_type: U_DWORD_R
      accuracy_decimals: 1
      filters:
        - multiply: 0.01

    - platform: modbus_controller
      modbus_controller_id: epever
      id: battery_rated_voltage
      name: "battery_rated_voltage"
      address: 0x3004
      unit_of_measurement: "V"
      register_type: read
      value_type: U_WORD
      accuracy_decimals: 1
      filters:
        - multiply: 0.01

    - platform: modbus_controller
      modbus_controller_id: epever
      id: battery_rated_current
      name: "battery_rated_current"
      address: 0x3005
      unit_of_measurement: "A"
      register_type: read
      value_type: U_WORD
      accuracy_decimals: 1
      filters:
        - multiply: 0.01

    - platform: modbus_controller
      modbus_controller_id: epever
      id: battery_rated_power
      name: "battery_rated_power"
      address: 0x3006
      unit_of_measurement: "W"
      register_type: read
      value_type: U_DWORD_R
      accuracy_decimals: 1
      filters:
        - multiply: 0.01

    - platform: modbus_controller
      modbus_controller_id: epever id: charging_mode
      name: "charging_mode"
      address: 0x3008
      unit_of_measurement: ""
      register_type: read
      value_type: U_WORD
      accuracy_decimals: 0


To minimize the required transactions all registers with the same base address are read in one request.
The response is mapped to the sensor based on ``register_count`` and offset in bytes. For example:

**Request**

+-----------+-----------------------------------------+
| data      | description                             |
+===========+=========================================+
| 0x1  (01) | device address                          |
+-----------+-----------------------------------------+
| 0x4  (04) | function code 4 (Read Input Registers)  |
+-----------+-----------------------------------------+
| 0x30 (48) | start address high byte                 |
+-----------+-----------------------------------------+
| 0x0  (00) | start address low byte                  |
+-----------+-----------------------------------------+
| 0x0  (00) | number of registers to read high byte   |
+-----------+-----------------------------------------+
| 0x9  (09) | number of registers to read low byte    |
+-----------+-----------------------------------------+
| 0x3f (63) | crc                                     |
+-----------+-----------------------------------------+
| 0xc  (12) | crc                                     |
+-----------+-----------------------------------------+



**Response**

+--------+------------+--------------------+--------------------------------------------+
| offset | data       | value (type)       | description                                |
+========+============+====================+============================================+
|   H    | 0x1  (01)  |                    | device address                             |
+--------+------------+--------------------+--------------------------------------------+
|   H    | 0x4  (04)  |                    | function code                              |
+--------+------------+--------------------+--------------------------------------------+
|   H    | 0x12 (18)  |                    | byte count                                 |
+--------+------------+--------------------+--------------------------------------------+
|   0    | 0x27 (39)  | U_WORD             | array_rated_voltage  high byte             |
+--------+------------+--------------------+--------------------------------------------+
|   1    | 0x10 (16)  | 0x2710 (100000)    | array_rated_voltage  low byte              |
+--------+------------+--------------------+--------------------------------------------+
|   2    | 0x7  (7)   | U_WORD             | array_rated_current  high byte             |
+--------+------------+--------------------+--------------------------------------------+
|   3    | 0xd0 (208) | 0x7d0 (2000)       | array_rated_current  low byte              |
+--------+------------+--------------------+--------------------------------------------+
|   4    | 0xcb (203) | U_DWORD_R          | array_rated_power high byte of low word    |
+--------+------------+--------------------+--------------------------------------------+
|   5    | 0x20 (32)  | spans 2 register   | array_rated_power low byte of low word     |
+--------+------------+--------------------+--------------------------------------------+
|   6    | 0x0  (0)   |                    | array_rated_power high byte of high word   |
+--------+------------+--------------------+--------------------------------------------+
|   7    | 0x0  (0)   | 0x0000CB20 (52000) | array_rated_power low byte of high word    |
+--------+------------+--------------------+--------------------------------------------+
|   8    | 0x9  (09)  | U_WORD             | battery_rated_voltage high byte            |
+--------+------------+--------------------+--------------------------------------------+
|   9    | 0x60 (96)  | 0x960 (2400)       | battery_rated_voltage low byte             |
+--------+------------+--------------------+--------------------------------------------+
|   10   | 0x7  (07)  | U_WORD             | battery_rated_current high word            |
+--------+------------+--------------------+--------------------------------------------+
|   11   | 0xd0 (208) | 0x7d0 (2000)       | battery_rated_current high word            |
+--------+------------+--------------------+--------------------------------------------+
|   12   | 0xcb (203) | U_DWORD_R          | battery_rated_power high byte of low word  |
+--------+------------+--------------------+--------------------------------------------+
|   13   | 0x20 (32)  | spans 2 register   | battery_rated_power low byte of low word   |
+--------+------------+--------------------+--------------------------------------------+
|   14   | 0x0  (0)   |                    | battery_rated_power high byte of high word |
+--------+------------+--------------------+--------------------------------------------+
|   15   | 0x0  (0)   | 0x0000CB20 (52000) | battery_rated_power low byte of high word  |
+--------+------------+--------------------+--------------------------------------------+
|   16   | 0x0  (0)   | U_WORD             | charging_mode high byte                    |
+--------+------------+--------------------+--------------------------------------------+
|   17   | 0x2  (02)  | 0x2 (MPPT)         | charging_mode low  byte                    |
+--------+------------+--------------------+--------------------------------------------+
|   C    | 0x2f (47)  |                    | crc                                        |
+--------+------------+--------------------+--------------------------------------------+
|   C    | 0x31 (49)  |                    | crc                                        |
+--------+------------+--------------------+--------------------------------------------+


.. note::

    Write support is only implemented for switches and selects; however, the C++ code provides the required API to write to a Modbus device.

    These methods can be called from a lambda.

    Here is an example how to set config values to for an EPEVER Trace AN controller.
    The code synchronizes the localtime of MCU to the epever controller
    The time is set by writing 12 bytes to register 0x9013.
    Then battery charge settings are sent.

    .. code-block:: yaml

        esphome:
          on_boot:
            ## configure controller settings at setup
            ## make sure priority is lower than setup_priority of modbus_controller
            priority: -100
            then:
              - lambda: |-
                  // get local time and sync to controller
                  time_t now = ::time(nullptr);
                  struct tm *time_info = ::localtime(&now);
                  int seconds = time_info->tm_sec;
                  int minutes = time_info->tm_min;
                  int hour = time_info->tm_hour;
                  int day = time_info->tm_mday;
                  int month = time_info->tm_mon + 1;
                  int year = time_info->tm_year % 100;
                  esphome::modbus_controller::ModbusController *controller = id(epever);
                  // if there is no internet connection localtime returns year 70
                  if (year != 70) {
                    // create the payload
                    std::vector<uint16_t> rtc_data = {uint16_t((minutes << 8) | seconds), uint16_t((day << 8) | hour),
                                                      uint16_t((year << 8) | month)};
                    // Create a Modbus command item with the time information as the payload
                    esphome::modbus_controller::ModbusCommandItem set_rtc_command =
                        esphome::modbus_controller::ModbusCommandItem::create_write_multiple_command(controller, 0x9013, 3, rtc_data);
                    // Submit the command to the send queue
                    epever->queue_command(set_rtc_command);
                    ESP_LOGI("ModbusLambda", "EPSOLAR RTC set to %02d:%02d:%02d %02d.%02d.%04d", hour, minutes, seconds, day, month,
                            year + 2000);
                  }
                  // Battery settings
                  // Note: these values are examples only and apply my AGM Battery
                  std::vector<uint16_t> battery_settings1 = {
                      0,       // 9000 Battery Type 0 =  User
                      0x0073,  // 9001 Battery Cap 0x55 == 115AH
                      0x012C,  // 9002 Temp compensation -3V /°C/2V
                      0x05DC,  // 9003 0x5DC == 1500 Over Voltage Disconnect Voltage 15,0
                      0x058C,  // 9004 0x58C == 1480 Charging Limit Voltage 14,8
                      0x058C,  // 9005 Over Voltage Reconnect Voltage 14,8
                      0x05BF,  // 9006 Equalize Charging Voltage 14,6
                      0x05BE,  // 9007 Boost Charging Voltage 14,7
                      0x0550,  // 9008 Float Charging Voltage 13,6
                      0x0528,   // 9009 Boost Reconnect Charging Voltage 13,2
                      0x04C4,  // 900A Low Voltage Reconnect Voltage 12,2
                      0x04B0,  // 900B Under Voltage Warning Reconnect Voltage 12,0
                      0x04BA,  // 900c Under Volt. Warning Volt 12,1
                      0x04BA,  // 900d Low Volt. Disconnect Volt. 11.8
                      0x04BA   // 900E Discharging Limit Voltage 11.8
                  };

                  // Boost and equalization periods
                  std::vector<uint16_t> battery_settings2 = {
                      0x0000,  // 906B Equalize Duration (min.) 0
                      0x0075   // 906C Boost Duration (aka absorb) 117 mins
                  };
                  esphome::modbus_controller::ModbusCommandItem set_battery1_command =
                      esphome::modbus_controller::ModbusCommandItem::create_write_multiple_command(controller, 0x9000, battery_settings1.size() ,
                                                                                                  battery_settings1);

                  esphome::modbus_controller::ModbusCommandItem set_battery2_command =
                      esphome::modbus_controller::ModbusCommandItem::create_write_multiple_command(controller, 0x906B, battery_settings3.size(),
                                                                                                  battery_settings2);
                  delay(200) ;
                  controller->queue_command(set_battery1_command);
                  delay(200) ;
                  controller->queue_command(set_battery2_command);
                  ESP_LOGI("ModbusLambda", "EPSOLAR Battery set");

        uart:
          id: mod_bus
          tx_pin: GPIOXX
          rx_pin: GPIOXX
          baud_rate: 115200
          stop_bits: 1

        modbus:
          #flow_control_pin: GPIOXX
          send_wait_time: 200ms
          id: mod_bus_epever

        modbus_controller:
          - id: epever
            ## the Modbus device addr
            address: 0x1
            modbus_id: mod_bus_epever
            command_throttle: 0ms
            setup_priority: -10
            update_interval: ${updates}

        sensor:
          - platform: modbus_controller
            modbus_controller_id: epever
            id: array_rated_voltage
            name: "array_rated_voltage"
            address: 0x3000
            unit_of_measurement: "V"
            register_type: read
            value_type: U_WORD
            accuracy_decimals: 1
            filters:
              - multiply: 0.01

          - platform: modbus_controller
            modbus_controller_id: epever
            id: array_rated_current
            name: "array_rated_current"
            address: 0x3001
            unit_of_measurement: "A"
            register_type: read
            value_type: U_WORD
            accuracy_decimals: 2
            filters:
              - multiply: 0.01

          - platform: modbus_controller
            modbus_controller_id: epever
            id: array_rated_power
            name: "array_rated_power"
            address: 0x3002
            unit_of_measurement: "W"
            register_type: read
            value_type: U_DWORD_R
            accuracy_decimals: 1
            filters:
              - multiply: 0.01

.. _modbusseealso:

See Also
--------

- :doc:`/components/modbus`
- :doc:`/components/sensor/modbus_controller`
- :doc:`/components/binary_sensor/modbus_controller`
- :doc:`/components/output/modbus_controller`
- :doc:`/components/switch/modbus_controller`
- :doc:`/components/number/modbus_controller`
- :doc:`/components/select/modbus_controller`
- :doc:`/components/text_sensor/modbus_controller`
- `Modbus RTU Protocol Description <https://www.modbustools.com/modbus.html>`__
- `EPEVER MPPT Solar Charge Controller (Tracer-AN Series) <https://devices.esphome.io/devices/epever_mptt_tracer_an>`__
- `Genvex, Nibe, Alpha-Innotec heat recovery ventilation <https://devices.esphome.io/devices/Genvex-Nibe-AlphaInnotec-heat-recovery-ventilation>`__
- :ghedit:`Edit`