• MCU/module: ESP32-C3-MINI-1U-N4
• Wireless mode: ESP-NOW
• Sensors:
  • TMP117-compatible temperature sensor on I2C
  • LIS2DW12 accelerometer on I2C

• GPIO4 -> I2C SDA
• GPIO5 -> I2C SCL
• GPIO1 -> TMP117 ALERT
• GPIO0 -> LIS2DW12 INT1
• GPIO6 -> Charger status input
• GPIO9 -> BOOT strap
• TXD0 / RXD0 -> pogo UART programming/debug

Cpp
#include <WiFi.h>
#include <esp_now.h>
#include <Wire.h>
#include <Adafruit_TMP117.h>
#include <SparkFun_LIS2DW12.h>

static const int PIN_I2C_SDA = 4;
static const int PIN_I2C_SCL = 5;
static const int PIN_TMP_ALERT = 1;
static const int PIN_ACCEL_INT = 0;
static const int PIN_CHG_STAT = 6;

Adafruit_TMP117 tmp117;
LIS2DW12 accel;

uint8_t peerAddress[] = {0x24, 0x6F, 0x28, 0x00, 0x00, 0x00}; // TODO: replace

struct Payload {
  float temperature_c;
  float ax_g;
  float ay_g;
  float az_g;
  uint8_t charging_active;
};

void onDataSent(const wifi_tx_info_t *info, esp_now_send_status_t status) {
  (void)info;
  Serial.print("ESP-NOW send status: ");
  Serial.println(status == ESP_NOW_SEND_SUCCESS ? "OK" : "FAIL");
}

void setupEspNow() {
  WiFi.mode(WIFI_STA);
  if (esp_now_init() != ESP_OK) {
    Serial.println("ESP-NOW init failed");
    return;
  }

  esp_now_register_send_cb(onDataSent);

  esp_now_peer_info_t peerInfo = {};
  memcpy(peerInfo.peer_addr, peerAddress, 6);
  peerInfo.channel = 0;
  peerInfo.encrypt = false;

  if (!esp_now_is_peer_exist(peerAddress)) {
    if (esp_now_add_peer(&peerInfo) != ESP_OK) {
      Serial.println("Failed to add ESP-NOW peer");
    }
  }
}

void setupSensors() {
  Wire.begin(PIN_I2C_SDA, PIN_I2C_SCL);

  if (!tmp117.begin()) {
    Serial.println("TMP117 not found");
  }

  if (!accel.begin()) {
    Serial.println("LIS2DW12 not found");
  } else {
    accel.setMode(LIS2DW12_MODE_LOW_POWER);
    accel.setDataRate(LIS2DW12_ODR_50HZ);
    accel.setRange(LIS2DW12_RANGE_2G);
  }

  pinMode(PIN_TMP_ALERT, INPUT);
  pinMode(PIN_ACCEL_INT, INPUT);
  pinMode(PIN_CHG_STAT, INPUT_PULLUP);
}

void setup() {
  Serial.begin(115200);
  delay(200);
  setupSensors();
  setupEspNow();
}

void loop() {
  Payload payload{};

  payload.temperature_c = tmp117.readTemperature();
  payload.ax_g = accel.x;
  payload.ay_g = accel.y;
  payload.az_g = accel.z;
  payload.charging_active = digitalRead(PIN_CHG_STAT) == LOW ? 1 : 0;

  esp_now_send(peerAddress, reinterpret_cast<const uint8_t*>(&payload), sizeof(payload));

  Serial.print("T=");
  Serial.print(payload.temperature_c);
  Serial.print(" C, A=");
  Serial.print(payload.ax_g); Serial.print(", ");
  Serial.print(payload.ay_g); Serial.print(", ");
  Serial.print(payload.az_g);
  Serial.print(", CHG=");
  Serial.println(payload.charging_active);

  delay(1000);
}

1. Confirm the peer MAC address for the ESP-NOW receiver.
2. Verify the TMP117 and LIS2DW12 I2C addresses match the hardware strapping.
3. Check that the pogo UART path works at 115200 baud.
4. Confirm charger-status polarity in hardware bring-up.
5. If low-power firmware is required later, switch the reporting loop to a timer / wake-on-interrupt strategy.