How to Use STM-32 NUCLEO-F401RE: Examples, Pinouts, and Specs

The STM-32 NUCLEO-F401RE is a development board manufactured by STMicroelectronics, featuring the STM32F401RE microcontroller. This board is designed for rapid prototyping and development of embedded applications. It provides a wide range of interfaces, connectivity options, and compatibility with Arduino and ST morpho headers, making it versatile for various projects.

• IoT (Internet of Things) devices
• Robotics and automation systems
• Sensor data acquisition and processing
• Prototyping for industrial and consumer electronics
• Educational purposes for learning embedded systems

• Microcontroller: STM32F401RE (ARM Cortex-M4, 32-bit, 84 MHz)
• Flash Memory: 512 KB
• SRAM: 96 KB
• Operating Voltage: 3.3V
• Input Voltage (via USB): 5V
• Input Voltage (via VIN): 7V to 12V
• Digital I/O Pins: 50 (shared between Arduino and ST morpho headers)
• Analog Input Pins: 6 (12-bit ADC)
• PWM Output Pins: 12
• Communication Interfaces:
  • 3x USART/UART
  • 3x SPI
  • 2x I2C
• Onboard Debugger: ST-LINK/V2-1
• Connectivity: USB, Arduino Uno R3 compatibility, ST morpho headers
• Dimensions: 68.6 mm x 53.3 mm

The STM-32 NUCLEO-F401RE features two main pin headers: Arduino Uno R3-compatible headers and ST morpho headers. Below is a summary of the pin configuration:

1. Powering the Board:

   • Connect the board to your computer via the micro-USB cable for power and programming.
   • Alternatively, supply power through the VIN pin (7V-12V) or the 5V pin.

2. Programming the Board:

   • Use the onboard ST-LINK/V2-1 debugger to program the microcontroller.
   • Compatible with STM32CubeIDE, Keil, IAR, and Arduino IDE.

3. Connecting Peripherals:

   • Use the Arduino Uno R3-compatible headers for shields and modules.
   • Use the ST morpho headers for advanced GPIO and peripheral access.

4. Uploading Code:

   • Write your code in the IDE of your choice.
   • Compile and upload the code via the ST-LINK interface.

• Ensure the input voltage does not exceed the specified range to avoid damage.
• Use decoupling capacitors when connecting external components to reduce noise.
• Avoid connecting high-current loads directly to the GPIO pins.
• Use proper level shifters when interfacing with 5V logic devices.

Below is an example code to blink an LED connected to pin D13:

// Blink an LED on pin D13 of the STM-32 NUCLEO-F401RE

void setup() {
  pinMode(13, OUTPUT); // Set pin D13 as an output
}

void loop() {
  digitalWrite(13, HIGH); // Turn the LED on
  delay(1000);            // Wait for 1 second
  digitalWrite(13, LOW);  // Turn the LED off
  delay(1000);            // Wait for 1 second
}

1. The board is not detected by the computer:

   • Ensure the USB cable is properly connected and functional.
   • Check if the ST-LINK driver is installed on your computer.

2. Code upload fails:

   • Verify that the correct board and port are selected in the IDE.
   • Ensure no other application is using the ST-LINK interface.

3. The board does not power on:

   • Check the power source and ensure the input voltage is within the specified range.
   • Inspect the USB cable or external power supply for faults.

4. GPIO pins are not functioning as expected:

   • Confirm the pin mode is correctly configured in the code.
   • Check for short circuits or incorrect connections.

Q: Can I use the STM-32 NUCLEO-F401RE with 5V logic devices?
A: The board operates at 3.3V logic levels. Use level shifters to interface with 5V devices.

Q: Is the board compatible with Arduino shields?
A: Yes, the board is compatible with most Arduino Uno R3 shields.

Q: How do I reset the board?
A: Press the RESET button on the board or use the NRST pin.

Q: Can I use an external clock source?
A: Yes, connect the external clock to the OSC_IN and OSC_OUT pins on the ST morpho header.