STM32 RF Link

This project demonstrates a simple accident detection and notification system using STM32F4 microcontrollers. It consists of two main modules:

• Master: Detects button presses, toggles an LED, and beeps a buzzer.
• Slave: Detects an accident signal, displays a message on an I2C LCD, and sends a notification via Bluetooth (HC-05).

Features

• Accident detection using GPIO input.
• Visual notification on an I2C LCD display.
• Wireless notification via Bluetooth HC-05 module.
• Audible alert using a buzzer.
• Simple master-slave communication logic.

Hardware Connections

Master (master.c)

• Button input: PA0
• LED output: PC13
• Buzzer output: PB8

Slave (slave.c)

• Accident input: PA1
• LCD I2C: PB6 (SCL), PB7 (SDA)
• Bluetooth HC-05: PA2 (TX), PA3 (RX)
• Status LED: PC13

How It Works

• Master: Toggles an LED and beeps the buzzer when the button is pressed.
• Slave: When an accident is detected (PA1 high), it:
  • Turns ON the status LED (PC13).
  • Displays "Accident detected. EMERGENCY" on the LCD.
  • Sends "Accident detected. EMERGENCY" to the HC-05 Bluetooth module.

Usage

1. Connect the hardware as described above.
2. Flash master.c to one STM32F4 board and slave.c to another.
3. Power both boards.
4. Press the button on the master to simulate an event.
5. The slave will display and send the accident message when triggered.

Software Used

• Keil uVision5 (IDE for STM32 programming) (https://www.keil.com/)
• Serial Bluetooth Terminal (Android app for checking Bluetooth messages) (https://play.google.com/store/apps/details?id=de.kai_morich.serial_bluetooth_terminal)

Modules Used

• Radio Frequency Module: Rf434 (https://amzn.in/d/04wg406)
• LCD: I2C LCD (https://amzn.in/d/d26OnqX)
• Bluetooth Module: HC-05 (https://amzn.in/d/h2dZF0w)
• Buzzer: (https://amzn.in/d/2LMKK0g)
• STM32F401: 2 Board with st-link debugger (https://amzn.in/d/2jYhwrk) (https://amzn.in/d/bVoZ0AD)

Schematic Diagram

Master

Slave