lora-sender.yaml

# LoRa Mailbox Sender v74 - Final Production
# 
# Hardware: Heltec WiFi LoRa 32 V3 (ESP32-S3 + SX1262)
# Power: 6x 18650 Li-ion parallel (12000mAh)
# Deep sleep: ~2.6-3.4mA
# Expected battery life: ~4-6 months
#
# Wakeup: GPIO5 (reed switch/magnetic contact)
# Battery ADC: GPIO7 (voltage divider)
#
# Message format:
#   1|4.02         = Mail received, battery voltage
#   1|3.35|LOW_BAT = Mail received, low battery (<3.4V)
#   W|4.02|LID_OPEN = Lid open for 5+ minutes

esphome:
  name: lora-sender
  friendly_name: LoRa Mailbox Sender
  on_boot:
    priority: -100
    then:
      - component.update: bat_voltage

esp32:
  board: esp32-s3-devkitc-1
  framework:
    type: esp-idf

logger:
  baud_rate: 0

# WiFi disabled for battery operation
# Uncomment for maintenance/debugging (flash via USB)
# wifi:
#   ssid: !secret wifi_ssid
#   password: !secret wifi_password

# api:
#   encryption:
#     key: "your-api-key-here"

# ota:
#   - platform: esphome
#     password: "your-ota-password"

globals:
  - id: packets_sent
    type: bool
    restore_value: false
    initial_value: 'false'
  - id: warning_sent
    type: bool
    restore_value: false
    initial_value: 'false'

deep_sleep:
  id: deep_sleep_mode
  wakeup_pin:
    number: GPIO5
    allow_other_uses: true
    mode:
      input: true
      pullup: true
  wakeup_pin_mode: KEEP_AWAKE

sensor:
  - platform: adc
    pin: GPIO7
    id: bat_voltage
    name: "Battery Voltage"
    unit_of_measurement: V
    update_interval: never
    accuracy_decimals: 2
    attenuation: 12db
    filters:
      - multiply: 2.0  # Voltage divider ratio

binary_sensor:
  - platform: gpio
    pin:
      number: GPIO5
      allow_other_uses: true
      mode:
        input: true
        pullup: true
      inverted: true
    name: "Mailbox Lid"
    id: mailbox_lid
    device_class: door
    filters:
      - delayed_on: 100ms
      - delayed_off: 100ms

spi:
  clk_pin: GPIO9
  mosi_pin: GPIO10
  miso_pin: GPIO11

sx126x:
  id: lora_radio
  cs_pin: GPIO8
  rst_pin: GPIO12
  busy_pin: GPIO13
  dio1_pin: GPIO14
  hw_version: sx1262
  tcxo_voltage: 1_8V
  tcxo_delay: 30ms
  rf_switch: true
  modulation: LORA
  sync_value: [0x14, 0x24]
  frequency: 868000000      # EU868 band
  bandwidth: 125_0kHz
  spreading_factor: 12      # Max range
  coding_rate: CR_4_8
  preamble_size: 10
  crc_enable: true
  pa_power: 14              # dBm

output:
  - platform: gpio
    pin: GPIO35
    id: status_led

interval:
  # Heartbeat LED blink while awake
  - interval: 30s
    then:
      - output.turn_on: status_led
      - delay: 100ms
      - output.turn_off: status_led
  
  # Mail notification - sends 3x packets, then sleeps
  - interval: 10s
    startup_delay: 10s
    then:
      - if:
          condition:
            lambda: 'return !id(packets_sent);'
          then:
            - lambda: 'id(packets_sent) = true;'
            - repeat:
                count: 3
                then:
                  - sx126x.send_packet:
                      id: lora_radio
                      data: !lambda |-
                        float voltage = id(bat_voltage).state;
                        char msg[24];
                        if (voltage < 3.4) {
                          snprintf(msg, sizeof(msg), "1|%.2f|LOW_BAT", voltage);
                        } else {
                          snprintf(msg, sizeof(msg), "1|%.2f", voltage);
                        }
                        std::string s(msg);
                        return std::vector<uint8_t>(s.begin(), s.end());
                  - output.turn_on: status_led
                  - delay: 150ms
                  - output.turn_off: status_led
                  - delay: 850ms
            - sx126x.set_mode_sleep: lora_radio
            - delay: 100ms
            - deep_sleep.enter: deep_sleep_mode
  
  # Lid open warning - if lid stays open 5 min, send warning
  - interval: 60s
    startup_delay: 300s
    then:
      - if:
          condition:
            lambda: 'return !id(warning_sent);'
          then:
            - lambda: 'id(warning_sent) = true;'
            - repeat:
                count: 3
                then:
                  - sx126x.send_packet:
                      id: lora_radio
                      data: !lambda |-
                        float voltage = id(bat_voltage).state;
                        char msg[24];
                        snprintf(msg, sizeof(msg), "W|%.2f|LID_OPEN", voltage);
                        std::string s(msg);
                        return std::vector<uint8_t>(s.begin(), s.end());
                  - output.turn_on: status_led
                  - delay: 150ms
                  - output.turn_off: status_led
                  - delay: 850ms
            - sx126x.set_mode_sleep: lora_radio
            - delay: 100ms
            - deep_sleep.enter: deep_sleep_mode