TOMZN TOMPD-63-WiFi

Programming

Internally, it uses the TUYA CBU chip, which is based on the BK7231N.

You need to solder 5 wires for the GND, +3v3, RX, TX and CEN (Reset) signals in order to connect them to a USB-to-serial (TTL) adapter.

Of course you also need USB-to-serial converter, and +3v3 supply (I'm using power out on my USB-to-serial converter),

You can flash the device using ltchiptool or directly with esphome upload <your-config.yaml> command from the console or ESPHome web GUI

If flashing fails, desoldering the CBU chip may help by improving 3.3V line stability.

Dataponts

[01:21:47][C][tuya:041]: Tuya:
[01:21:47][C][tuya:058]:   Datapoint 1: int value (value: 438)
[01:21:47][C][tuya:056]:   Datapoint 11: switch (value: OFF)
[01:21:47][C][tuya:058]:   Datapoint 13: int value (value: 0)
[01:21:47][C][tuya:054]:   Datapoint 6: raw (value: 09.0A.00.0F.FA.00.03.59 (8))
[01:21:47][C][tuya:060]:   Datapoint 19: string value (value: )
[01:21:47][C][tuya:056]:   Datapoint 12: switch (value: OFF)
[01:21:47][C][tuya:056]:   Datapoint 16: switch (value: ON)
[01:21:47][C][tuya:058]:   Datapoint 15: int value (value: 18)
[01:21:47][C][tuya:058]:   Datapoint 101: int value (value: 230)
[01:21:47][C][tuya:064]:   Datapoint 9: bitmask (value: 0)
[01:21:47][C][tuya:054]:   Datapoint 17: raw (value: 03.01.00.0D.04.00.00.00 (8))
[01:21:47][C][tuya:054]:   Datapoint 18: raw (value: 01.01.00.1E.03.01.00.FF.04.01.00.C8 (12))
[01:21:47][C][tuya:074]:   Product: '{"p":"hiow4txw9gjrys7w","v":"1.0.0","m":0}

Basic ESPHome config

esphome:
  name: medidor-din-2
  friendly_name: medidor-din-2

bk72xx:
  board: generic-bk7231n-qfn32-tuya

# Disable logging
logger:
  baud_rate: 0
  
uart:
  baud_rate: 9600
  id: uart_tuya
  rx_pin: RX1
  tx_pin: TX1

tuya:
  uart_id: uart_tuya
  on_datapoint_update:
  - sensor_datapoint: 6
    datapoint_type: raw
    then:
      - lambda: |-
          ESP_LOGD("main", "on_datapoint_update %s", format_hex_pretty(x).c_str());
          id(voltage).publish_state((x[0] << 8 | x[1]) * 0.1);
          id(current).publish_state((x[3] << 8 | x[4]) * 0.001);
          id(power).publish_state((x[6] << 8 | x[7]) * 1);

switch:
  - platform: tuya
    switch_datapoint: 16
    name: "On"

sensor:
  - platform: template
    id: voltage
    name: "Volt"
    unit_of_measurement: "V"
    icon: "mdi:sine-wave"
    accuracy_decimals: 1
  - platform: template
    id: current
    name: "Curent"
    icon: "mdi:current-ac"
    unit_of_measurement: "A"
    accuracy_decimals: 2
  - platform: template
    id: power
    name: "Power"
    icon: "mdi:flash"
    unit_of_measurement: "W"
    accuracy_decimals: 0
  - platform: tuya
    name: "Total Energy"
    sensor_datapoint: 1
    unit_of_measurement: "kWh"
    accuracy_decimals: 2
    icon: "mdi:lightning-bolt"
    filters:
      - multiply: 0.01  
  - platform: tuya
    name: "Leakage Current"
    sensor_datapoint: 15
    unit_of_measurement: "mA"
    accuracy_decimals: 0
    icon: "mdi:flash-alert"