TomZN TOB9-VAP

bk72xx global Comes with ESPHome misc

Notes

Uses BL0942 for energy monitoring, which requires calibration
Uses an H-Bridge for controlling the output instead of a standard relay. One key difference is that the H-Bridge retains the last position upon power off without the need of restore_mode

Product images

Programming

Tuya Cloudcutter was not able to work for this device (with firmware v1.0.15). If your device has an older firmware, it may be worth a try. This device is powered by a CBU board (BK7231N), you can read LibreTiny’s instructions on how to flash it. Disassembling this device is simple, provided you find a way to remove the golden tubes. Here is one way:

GPIO Pinout

Pin	Function	Notes
GPIO09	Red LED	inverted
GPIO10	RX for BL0942	RX1
GPIO11	TX for BL0942	TX1
GPIO15	Blue LED (status)	inverted
GPIO17	Button	inverted
GPIO24	Bridge forward	pulse
GPIO26	Bridge reverse	pulse

Basic Configuration

esphome:
  name: TomZN.TOB9-VAP
  min_version: 2024.12.0
bk72xx:
  board: cbu
logger:
captive_portal:
uart:
  tx_pin: TX1
  rx_pin: RX1
  baud_rate: 4800
  stop_bits: 1
binary_sensor:
  - platform: gpio
    id: power_button
    pin:
      number: 17
      inverted: true
      mode: INPUT_PULLUP
    on_multi_click:
      - timing:
          - ON for at most 1s
          - OFF for at least 0.2s
        then:
          switch.toggle: main_switch
      - timing:
          - ON for at least 4s
        then:
          button.press: reset
output:
  - platform: libretiny_pwm
    id: red_led_output
    pin:
      number: P9
      inverted: true
light:
  - platform: status_led
    id: blue_led
    pin:
      number: P15
      inverted: true
  - platform: monochromatic
    id: red_led
    output: red_led_output
switch:
  - platform: hbridge
    name: Switch
    id: main_switch
    on_pin: GPIO24
    off_pin: GPIO26
    pulse_length: 60ms
    wait_time: 30ms
    on_turn_on:
      light.turn_on: red_led
    on_turn_off:
      light.turn_off: red_led
sensor:
  - platform: bl0942
    line_frequency: 50Hz
    update_interval: 10s
    current:
      name: Current
      filters:
        # The chip reports some current even when there is no load
        - lambda: if (x < 0.02) return 0.0; else return x;
    voltage:
      name: Voltage
    power:
      name: Power
      filters:
        # The chip reports some power even when there is no load
        - lambda: if (x < 0.5) return 0.0; else return x;
    energy:
      name: Energy
      unit_of_measurement: kWh
    frequency:
      name: Frequency
      accuracy_decimals: 2