TMP102 Basic Temperature Reading Example

This example demonstrates how to use the TMP102 temperature sensor with the ESP32 using the ESP-IDF framework. The application initializes the TMP102 sensor, configures it, and periodically logs temperature readings along with alert pin and register states.

Features

Initialization: Configures the TMP102 sensor and GPIO for the ALERT pin.
Temperature Reading: Reads temperature in Celsius.
Alert Monitoring: Reads ALERT pin state and internal alert register status.
Power Management: Utilizes sleep and wakeup modes to conserve power.
Custom Settings: Configures fault tolerance, alert polarity, conversion rate, extended mode, and temperature thresholds.

Hardware Requirements

ESP32 Development Board
TMP102 Temperature Sensor
I2C Pins:
- SCL connected to GPIO 14
- SDA connected to GPIO 13
ALERT Pin:
- Connected to GPIO 10 with a pull-up resistor.

Connections

TMP102 Pin	ESP32 Pin	Description
VCC	3.3V	Power supply
GND	GND	Ground
SCL	GPIO 14	I2C Clock Line
SDA	GPIO 13	I2C Data Line
ALERT	GPIO 10	Alert Output (input to ESP32)

Software Setup

Prerequisites

ESP-IDF v5.3 or later
TMP102 library integrated into your project.

Example Code Overview

#include "esp_log.h"
#include "freertos/FreeRTOS.h"
#include "freertos/task.h"
#include "driver/gpio.h"
#include "tmp102.h"

#define ALERT_PIN GPIO_NUM_10 
#define T_HIGH_C 32.0
#define T_LOW_C 30.0 

static const char *TAG = "tmp102_example";

void app_main(void)
{
    tmp102_config_t conf = {
        .addr = 0x48,
        .pin_scl = GPIO_NUM_14,
        .pin_sda = GPIO_NUM_13,
    };

    ESP_ERROR_CHECK(tmp102_init(&conf));

    gpio_config_t gpio_conf = {
        .pin_bit_mask = (1ULL << ALERT_PIN),
        .mode = GPIO_MODE_INPUT,
        .pull_up_en = GPIO_PULLUP_ENABLE,
        .pull_down_en = GPIO_PULLDOWN_DISABLE,
        .intr_type = GPIO_INTR_DISABLE,
    };

    ESP_ERROR_CHECK(gpio_config(&gpio_conf));

    ESP_ERROR_CHECK(tmp102_set_fault(0));
    ESP_ERROR_CHECK(tmp102_set_alert_polarity(1));
    ESP_ERROR_CHECK(tmp102_set_alert_mode(TMP102_COMPARATOR_MODE));
    ESP_ERROR_CHECK(tmp102_set_conversion_rate(2));
    ESP_ERROR_CHECK(tmp102_set_extended_mode(TMP102_EXTENDED_DISABLE));
    ESP_ERROR_CHECK(tmp102_set_high_temp_c(T_HIGH_C));
    ESP_ERROR_CHECK(tmp102_set_low_temp_c(T_LOW_C));

    while (1)
    {
        float temp = 0;
        bool alert_pin_state = 0;
        bool alert_register_state = 0;

        ESP_ERROR_CHECK(tmp102_wakeup());

        temp = tmp102_read_temp_c();
        alert_pin_state = gpio_get_level(ALERT_PIN);
        alert_register_state = tmp102_read_alert_status();

        ESP_ERROR_CHECK(tmp102_sleep());

        ESP_LOGI(TAG, "Temp in Celsius: %.2f", temp);
        ESP_LOGI(TAG, "Alert Pin: %d", alert_pin_state);
        ESP_LOGI(TAG, "Alert Register: %d", alert_register_state);

        vTaskDelay(1000 / portTICK_PERIOD_MS);
    }
}****