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 device .. figure:: /images/modbus.png :align: center :width: 25% The ``modbus_controller`` component uses the modbus component Hardware setup -------------- A RS 485 module connected to an ESP32, for example: .. figure:: /images/rs485.jpg See `How is this RS485 Module Working? `__ on stackexchange for more details The controller connects to the UART of the MCU. For ESP32 GPIO PIN 16 to TXD PIN 17 to RXD are the default ports but any other pins can be used as well. 3.3V to VCC and GND to GND. .. 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 and cause errors. Serial logging can be disabled by setting ``baud_rate: 0``. See :doc:`logger` for more details .. code-block:: yaml logger: 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 device Specify the modbus device address of the. - **command_throttle** (*Optional*, int): minimum time in milliseconds between 2 requests to the device. Default is 0ms Because some modbus devices limit the rate of requests the interval between sending requests to the device can be modified. - **update_interval** (*Optional*, :ref:`config-time`): The interval that the sensors should be checked. Defaults to 60 seconds. Example ------- The following code create 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 uart: id: mod_bus tx_pin: 17 rx_pin: 16 baud_rate: 115200 stop_bits: 1 modbus: flow_control_pin: 5 id: modbus1 modbus_controller: - id: epever ## the Modbus device addr address: 0x1 modbus_id: modbus1 setup_priority: -10 text_sensor: - name: "rtc_clock" platform: modbus_controller modbus_controller_id: epever id: rtc_clock internal: true register_type: holding address: 0x9013 register_count: 3 raw_encode: HEXBYTES response_size: 6 switch: - platform: modbus_controller modbus_controller_id: epever id: reset_to_fabric_default name: "Reset to Factory Default" register_type: coil address: 0x15 bitmask: 1 sensor: - platform: modbus_controller modbus_controller_id: epever name: "Battery Capacity" id: battery_capacity register_type: holding address: 0x9001 unit_of_measurement: "AH" value_type: U_WORD 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 | +------------+------------------+-----------+-----------+ For example, when reading register ``15``, a decimal value of ``12288`` 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: ventilation_system name: Alarm bit0 entity_category: diagnostic device_class: problem register_type: read address: 15 bitmask: 0x1 - platform: modbus_controller modbus_controller_id: ventilation_system name: Alarm bit1 entity_category: diagnostic device_class: problem register_type: read address: 15 bitmask: 0x2 - platform: modbus_controller modbus_controller_id: ventilation_system name: Alarm bit10 entity_category: diagnostic device_class: problem register_type: read address: 15 bitmask: 0x400 - platform: modbus_controller modbus_controller_id: ventilation_system name: Alarm bit15 entity_category: diagnostic device_class: problem register_type: read address: 15 bitmask: 0x8000 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. **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 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 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 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: 19 rx_pin: 18 baud_rate: 115200 stop_bits: 1 modbus: #flow_control_pin: 23 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 See Also -------- - :doc:`/components/sensor/modbus_controller` - :doc:`/components/binary_sensor/modbus_controller` - :doc:`/components/text_sensor/modbus_controller` - :doc:`/components/switch/modbus_controller` - :doc:`/components/number/modbus_controller` - :doc:`/components/output/modbus_controller` - :doc:`EPEVER MPPT Solar Charge Controller Tracer-AN Series` - `Modbus RTU Protocol Description `__ - :ghedit:`Edit`