LED Brightness Control with USART and LabVIEW

LabVIEW | LED Brightness Control | UART | PWM

This project demonstrates how to control the brightness of an LED connected to the NUCLEO STM32F446RE development board using LabVIEW and USART communication.

---

Overview

This project allows the user to configure the USART settings and send brightness levels to the STM32F446RE microcontroller using a LabVIEW .vi file. The microcontroller receives the data via USART and adjusts the brightness of the LED connected to pin PA0 using PWM.

---

Features

• LabVIEW Integration: Includes a LabVIEW .vi file located in the LabVIEW_files folder for easy configuration and control.
• USART Communication: Implements UART communication to receive brightness levels.
• PWM Control: Adjusts the LED brightness dynamically using a hardware timer (TIM2) and PWM.
• STM32F446RE: Compatible with the NUCLEO STM32F446RE development board.

---

How It Works

1. LabVIEW Configuration:

   • The user configures the USART settings and sends the brightness level (0–100%) to the STM32 board using the .vi file.

2. STM32 Board:

   • The board receives the data via USART2 and processes it.
   • The received brightness value is mapped to the PWM duty cycle for controlling the LED brightness.

3. PWM Output:

   • The TIM2 timer generates PWM signals, and the LED brightness is updated based on the received duty cycle.

---

Folder Structure

• LabVIEW_files: Contains the LabVIEW .vi file for user interaction.
• src: Contains the main application code, including:
  • main_app.c
  • main_app.h
  • Other related files.

---

Hardware Requirements

• NUCLEO STM32F446RE development board
• LED connected to pin PA0
• USB connection for USART communication
• LabVIEW software installed on the user's PC

---

Software Requirements

• Toolchains:
  • STM32CubeIDE or Keil uVision for code compilation and debugging
• LabVIEW:
  • For running the provided .vi file
• USART Drivers:
  • Ensure proper USB-to-serial drivers are installed for PC communication.

---

Setup and Usage

1. Hardware Setup:

   • Connect an LED to pin PA0 of the STM32 board.
   • Power the STM32 board using a USB cable.

2. Software Setup:

   • Open the LabVIEW .vi file from the LabVIEW_files folder.
   • Configure the USART settings to match the STM32 configuration (Baud rate: 115200, 8N1 format).

3. Run the Application:

   • Flash the compiled code to the STM32 board.
   • Use LabVIEW to send brightness values to the board.
   • Observe the LED brightness changing based on the input.

---

USART Configuration

• Baud Rate: 115200
• Word Length: 8 Bits
• Stop Bits: 1
• Parity: None
• Flow Control: None

---

LabVIEW Instructions

1. Open the .vi file in LabVIEW.
2. Set the desired brightness level (0-100%) using the provided slider or numeric input.
3. Click "SET" to transmit the brightness value to the STM32 board.

---

Code Highlights

• PWM Initialization:

  • TIM2 is configured to generate PWM signals with a frequency based on the system clock.
  • The duty cycle is dynamically updated using HAL_TIM_PWM_Start_IT.

• USART Handling:

  • Uses HAL_UART_Receive_IT to receive brightness values in interrupt mode.
  • The callback function HAL_UART_RxCpltCallback processes the received data.

---

Contributing

Contributions to enhance the project are welcome. Please follow the standard GitHub workflow:

1. Fork the repository.
2. Create a feature branch.
3. Commit your changes.
4. Submit a pull request.

---

License

This project is licensed under the MIT License.

---

Contact

For further assistance or inquiries, please contact: [your email here].