# esp32_ml307c

**Repository Path**: iotesp32/esp32_ml307c

## Basic Information

- **Project Name**: esp32_ml307c
- **Description**: No description available
- **Primary Language**: Unknown
- **License**: Not specified
- **Default Branch**: master
- **Homepage**: None
- **GVP Project**: No

## Statistics

- **Stars**: 0
- **Forks**: 0
- **Created**: 2025-12-31
- **Last Updated**: 2025-12-31

## Categories & Tags

**Categories**: Uncategorized

**Tags**: None

## README

# ML307 Module Test Project

This project demonstrates the use of ML307 4G LTE Cat.1 module with ESP32-C3.

## Features

- **Module Detection**: Automatic detection and initialization of ML307 module
- **HTTP GET Request**: Send HTTP GET requests using AT commands
- **MQTT Publish and Subscribe**: MQTT message publishing and subscription via ML307 module

## Hardware Configuration

- **MCU**: ESP32-C3
- **4G Module**: ML307 LTE Cat.1
- **UART Connection**:
  - ESP32 TX (GPIO21) → ML307 RX
  - ESP32 RX (GPIO20) → ML307 TX
  - Reset pin: Not used (GPIO_NUM_NC)

## Build and Flash

```bash
# Build the project
idf.py build

# Flash to device
idf.py flash

# Monitor serial output
idf.py monitor
```

Or use the combined command:

```bash
idf.py build flash monitor
```

## Configuration

### MQTT Configuration

MQTT broker and subscription are configured in the ML307 module (not in code). The code only uses:
- `MQTT_PUB_TOPIC`: MQTT publish topic (defined in code)

### HTTP Configuration

HTTP requests are sent directly using AT commands. The HTTP server configuration is done in the module.

## Project Structure

```
project-name/
├── main/
│   └── hello_world_main.cpp    # Main application code
├── components/
│   └── esp-ml307/              # ML307 module driver library
└── docs/                       # Development documentation
```

## Usage

1. Configure the ML307 module with MQTT broker and subscription topics
2. Flash the firmware to ESP32-C3
3. The application will:
   - Detect and initialize the ML307 module
   - Wait for network connection
   - Display module information (IMEI, ICCID, signal strength, etc.)
   - Send an HTTP GET request
   - Initialize MQTT and publish a test message
   - Continuously listen for MQTT messages

## Notes

- The MQTT subscription must be configured in the ML307 module before running
- The application uses callback-based message reception (no polling required)
- The main loop runs indefinitely to receive MQTT messages

## License

SPDX-License-Identifier: CC0-1.0