TOF sensors and solving problems with them

[jazzmonger]

vl53l0x tof sensor

I originally had planned for these sensors to be at the roof of the box measuring down. Unfortunately they aren't good enough to measure 1-2mm thick letters from 8-10" away. So instead, I mounted them to the bottom of the mailbox and drilled 2 holes for them to "see" up. This works flawlessly every time.

I use 2 of these sensors, one towards the front of the box and one towards the rear so there's a better chance of mail detection no matter where the mailman throws the mail into the box. This version of the sensor has enable pin XSHUT that can be used to enable them and put them in standby, thus drawing negligible current. When the ESP goes into sleep mode, I had to get on Discord to ask how to control those gpio's. The key was "allow_other_uses: true" as that flag allows the same gpio to be used as a switch that can be turned on & off. You learn something new every day!

I used hot glue to surround the sensors and wires to waterproof them, just don't cover the little "eye"in the top of the tof sensor. Our mail is never wet, even in torrential downpours and wind, so this should be just fine.

  - platform: vl53l0x
    name: "Mailbox Letter Distance"
    id: distance1
    address: 0x41
    enable_pin: 
      number: GPIO3
      allow_other_uses: true
    update_interval: ${update_interval}
    timeout: 200us
    long_range: False
  
  - platform: vl53l0x
    name: "Mailbox Letter Distance2"
    id: distance2
    address: 0x42
    enable_pin: 
      number: GPIO4
      allow_other_uses: true
    timeout: 200us
    update_interval: ${update_interval}

switch:
  - platform: gpio
    id: tof_enable1
    pin: 
      number: GPIO3 #D1
      allow_other_uses: true

  - platform: gpio
    id: tof_enable2
    pin: 
      number: GPIO4 #D2 
      allow_other_uses: true      

Then it becomes a case of how and when to turn those pins on & off. Here's how I did that:

esphome:
  name: mailbox-sensor
  friendly_name: mailbox sensor
  on_boot:    
    then: 
      - lambda: |-
          Wire.begin();  #explicitly sets up i2c communication 
          delay(100); 
      - switch.turn_on: tof_enable1
      - switch.turn_on: tof_enable2
  on_shutdown:
      priority: 200
      then:
      - switch.turn_off: tof_enable1
      - switch.turn_off: tof_enable2