phsensor.yaml

esphome:
  name: phsensor
  platform: ESP8266
  board: d1_mini

wifi:
  ssid: "xxx"
  password: "xxx"

  # Enable fallback hotspot (captive portal) in case wifi connection fails
  ap:
    ssid: "xxx"
    password: "xxx"

captive_portal:

# Enable logging
logger:

# Enable Home Assistant API
api:

ota:

sensor:
  # https://esphome.io/components/sensor/adc.html
  - platform: adc
    pin: A0
    id: ph
    name: "pH Sensor"
    update_interval: 1s
    unit_of_measurement: pH
    # https://esphome.io/components/sensor/index.html#sensor-filters
    filters:
      - median:
          window_size: 7
          send_every: 4
          send_first_at: 3
      # Measured voltage -> Actual pH (buffer solution)
      - calibrate_linear:
          - 0.59 -> 7.0
          - 0.71 -> 4.0

i2c:
  sda: D2
  scl: D1
  scan: true
  
display:
  - platform: lcd_pcf8574
    dimensions: 16x2
    lambda: |-
      it.printf(0, 0, "pH: %.2f", id(ph).state);
      if (id(ph).state < 4) {
        it.print(0, 1, "Very acidic");
      }
      else if (id(ph).state >= 4 && id(ph).state < 5) {
        it.print(0, 1, "Acidic");
      }
      else if (id(ph).state >= 5 && id(ph).state < 7) {
        it.print(0, 1, "Acidic-ish");
      }
      else if (id(ph).state >= 7 && id(ph).state < 8) {
        it.print(0, 1, "Neutral");
      }
      else if (id(ph).state >= 8 && id(ph).state < 10) {
        it.print(0, 1, "Alkaline-ish");
      }
      else if (id(ph).state >= 10 && id(ph).state < 11) {
        it.print(0, 1, "Alkaline");
      }
      else if (id(ph).state >= 11) {
        it.print(0, 1, "Very alkaline");
      }