7Segment_Display-Esp32-homeassistant.ino

#include <WiFi.h>
#include <PubSubClient.h>

//	    a
//	   ---
//	  |   |
//	f |   | b
//	  |   |
//	   --- <----- g
//	  |   |
//	e |   | c
//	  |   |
//	   ---
//      d

// https://docs.espressif.com/projects/esp-idf/en/stable/esp32c3/_images/esp32-c3-devkitc-02-v1-pinout.png
const int a=10;
const int b=20;
const int c=7;
const int d=5;
const int e=4;
const int f=1;
const int g=6;
const int dp=3;
const int resetPin = 2;

int prevResetState = HIGH;

WiFiClient espClient;
PubSubClient client(espClient);

void setup() {
  Serial.begin(9600);
  pinMode(a,OUTPUT);
  pinMode(b,OUTPUT);
  pinMode(c,OUTPUT);
  pinMode(d,OUTPUT);
  pinMode(e,OUTPUT);
  pinMode(f,OUTPUT);
  pinMode(g,OUTPUT);
  pinMode(dp,OUTPUT);
  pinMode(resetPin, INPUT_PULLUP);

  setupWifi("ssid", "password");
  client.setServer("homeassistant.local", 1883);
  client.setCallback(callback);
}

void reconnect() {
  while (!client.connected()) {
    Serial.print("Attempting MQTT connection...");
    if (client.connect("7SegmentDisplay")) {
      Serial.println("connected");
      client.publish("counter:client", "setup");
      client.subscribe("counter:server");
    } else {
      Serial.print("failed, rc=");
      Serial.print(client.state());
      Serial.println(" try again in 5 seconds");
      delay(5000);
    }
  }
}

void callback(char* topic, byte* payload, unsigned int length) {
  String payloadStr = "";
  for (int i = 0; i < length; i++) {
    payloadStr += (char)payload[i];
  }
  int counterValue = payloadStr.toInt();
  displayNumber(counterValue);
  client.publish("counter:client", "ack");
}

void loop() {
  int resetState = digitalRead(resetPin);
  if (resetState == LOW && prevResetState == HIGH) {
    client.publish("counter:client", "reset");
  }
  prevResetState = resetState;

  if (!client.connected()) {
    reconnect();
  }
  client.loop();
  delay(2); // allow the CPU to switch to other tasks
}

void setupWifi(const char* ssid, const char* password) {
  WiFi.mode(WIFI_STA);
  WiFi.begin(ssid, password);

  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }
  Serial.println("");
  Serial.print("Connected to ");
  Serial.println(ssid);
  Serial.print("IP address: ");
  Serial.println(WiFi.localIP());
}

void displayNumber(int number) {
  if (number == 0) {
    digitalWrite(a,HIGH);
    digitalWrite(b,HIGH);
    digitalWrite(c,HIGH);
    digitalWrite(d,HIGH);
    digitalWrite(e,HIGH);
    digitalWrite(f,HIGH);
    digitalWrite(g,LOW);
    digitalWrite(dp,LOW);
    return;
  }

  if (number == 1) {
    digitalWrite(a,LOW);
    digitalWrite(b,HIGH);
    digitalWrite(c,HIGH);
    digitalWrite(d,LOW);
    digitalWrite(e,LOW);
    digitalWrite(f,LOW);
    digitalWrite(g,LOW);
    digitalWrite(dp,LOW);
    return;
  }

  if (number == 2) {
    digitalWrite(a,HIGH);
    digitalWrite(b,HIGH);
    digitalWrite(c,LOW);
    digitalWrite(d,HIGH);
    digitalWrite(e,HIGH);
    digitalWrite(f,LOW);
    digitalWrite(g,HIGH);
    digitalWrite(dp,LOW);
    return;
  }

  if (number == 3) {
    digitalWrite(a,HIGH);
    digitalWrite(b,HIGH);
    digitalWrite(c,HIGH);
    digitalWrite(d,HIGH);
    digitalWrite(e,LOW);
    digitalWrite(f,LOW);
    digitalWrite(g,HIGH);
    digitalWrite(dp,LOW);
    return;
  }

  if (number == 4) {
    digitalWrite(a,LOW);
    digitalWrite(b,HIGH);
    digitalWrite(c,HIGH);
    digitalWrite(d,LOW);
    digitalWrite(e,LOW);
    digitalWrite(f,HIGH);
    digitalWrite(g,HIGH);
    digitalWrite(dp,LOW);
    return;
  }

  if (number == 5) {
    digitalWrite(a,HIGH);
    digitalWrite(b,LOW);
    digitalWrite(c,HIGH);
    digitalWrite(d,HIGH);
    digitalWrite(e,LOW);
    digitalWrite(f,HIGH);
    digitalWrite(g,HIGH);
    digitalWrite(dp,LOW);
    return;
  }

  if (number == 6) {
    digitalWrite(a,HIGH);
    digitalWrite(b,LOW);
    digitalWrite(c,HIGH);
    digitalWrite(d,HIGH);
    digitalWrite(e,HIGH);
    digitalWrite(f,HIGH);
    digitalWrite(g,HIGH);
    digitalWrite(dp,LOW);
    return;
  }

  if (number == 7) {
    digitalWrite(a,HIGH);
    digitalWrite(b,HIGH);
    digitalWrite(c,HIGH);
    digitalWrite(d,LOW);
    digitalWrite(e,LOW);
    digitalWrite(f,LOW);
    digitalWrite(g,LOW);
    digitalWrite(dp,LOW);
    return;
  }

  if (number == 8) {
    digitalWrite(a,HIGH);
    digitalWrite(b,HIGH);
    digitalWrite(c,HIGH);
    digitalWrite(d,HIGH);
    digitalWrite(e,HIGH);
    digitalWrite(f,HIGH);
    digitalWrite(g,HIGH);
    digitalWrite(dp,LOW);
    return;
  }

  if (number == 9) {
    digitalWrite(a,HIGH);
    digitalWrite(b,HIGH);
    digitalWrite(c,HIGH);
    digitalWrite(d,HIGH);
    digitalWrite(e,LOW);
    digitalWrite(f,HIGH);
    digitalWrite(g,HIGH);
    digitalWrite(dp,LOW);
    return;
  }

  // E
  digitalWrite(a,HIGH);
  digitalWrite(b,LOW);
  digitalWrite(c,LOW);
  digitalWrite(d,HIGH);
  digitalWrite(e,HIGH);
  digitalWrite(f,HIGH);
  digitalWrite(g,HIGH);
  digitalWrite(dp,LOW);
}

automations.yaml

- alias: mqtt count changed
  description: when counter value changes then publish message to board
  trigger:
    - platform: state
      entity_id:
        - counter.hearing_aid_battery_days
  condition: []
  action:
    - service: mqtt.publish
      metadata: {}
      data:
        topic: counter:server
        payload: '{{ states(''counter.hearing_aid_battery_days'') }}'
    - wait_for_trigger:
        - platform: mqtt
          topic: counter:client
          payload: ack
      timeout:
        hours: 0
        minutes: 0
        seconds: 10
        milliseconds: 0
    - if:
        - condition: template
          value_template: '{{ wait.trigger == none }}'
      then:
        - service: notify.pushover
          data:
            title: Did not receive ACK from counter board!
            message: :(
  mode: single
- alias: mqtt counter inc at 1am
  description: increment the counter value at 1am every day
  trigger:
    - platform: time
      at: 01:00:00
  condition: []
  action:
    - service: counter.increment
      metadata: {}
      data: {}
      target:
        entity_id: counter.hearing_aid_battery_days
  mode: single
- alias: mqtt counter reset
  description: reset the counter back to zero when a reset message is received
  trigger:
    - platform: mqtt
      topic: counter:client
      payload: reset
  condition: []
  action:
    - service: counter.reset
      target:
        entity_id:
          - counter.hearing_aid_battery_days
      data: {}
  mode: single
- alias: mqtt counter setup
  description: publish the counter value to the board when a setup message is received
  trigger:
    - platform: mqtt
      topic: counter:client
      payload: setup
  condition: []
  action:
    - delay:
        hours: 0
        minutes: 0
        seconds: 5
        milliseconds: 0
    - service: mqtt.publish
      metadata: {}
      data:
        topic: counter:server
        payload: '{{ states(''counter.hearing_aid_battery_days'') }}'
  mode: single

configuration.yaml

# Loads default set of integrations. Do not remove.
default_config:

# Load frontend themes from the themes folder
frontend:
  themes: !include_dir_merge_named themes

automation: !include automations.yaml
script: !include scripts.yaml
scene: !include scenes.yaml

counter:
  hearing_aid_battery_days:
    name: 'Hearing aid Battery Days'
    icon: 'mdi:battery-clock-outline'
    initial: 0
    step: 1
    minimum: 0
    maximum: 9

esp-battery-counter_bb.png