How to Use Teensy 4.0: Examples, Pinouts, and Specs

The Teensy 4.0 is a powerful microcontroller board built around the NXP i.MX RT1062 chip, featuring a 600 MHz ARM Cortex-M7 processor. It is designed for high-performance applications, offering 1 MB of RAM and 2 MB of flash memory. Despite its compact size, the Teensy 4.0 delivers exceptional processing power, making it ideal for demanding projects such as real-time audio processing, robotics, machine learning, and advanced control systems.

• Real-time audio synthesis and processing
• Robotics and motor control
• High-speed data acquisition and processing
• Machine learning and AI applications
• Advanced IoT devices
• Signal processing and scientific computing

• Processor: 600 MHz ARM Cortex-M7
• RAM: 1 MB
• Flash Memory: 2 MB
• Operating Voltage: 3.3V (logic level)
• Input Voltage: 5V via USB or external power
• Digital I/O Pins: 40 (all 3.3V logic)
• Analog Input Pins: 14 (12-bit ADC)
• PWM Pins: 31
• Communication Interfaces: UART, SPI, I2C, CAN, I2S
• USB: High-speed USB (480 Mbps)
• Dimensions: 1.4 x 0.7 inches (35.56 x 17.78 mm)

The Teensy 4.0 has a total of 48 pins, including digital, analog, and power pins. Below is a summary of the pin configuration:

1. Powering the Board:

   • Connect the Teensy 4.0 to your computer via a USB cable for power and programming.
   • Alternatively, supply 5V to the VIN pin for external power. Ensure the ground (GND) is connected.

2. Programming the Board:

   • Install the Arduino IDE and the Teensyduino add-on.
   • Select "Teensy 4.0" as the board in the Arduino IDE.
   • Write your code and upload it to the board via USB.

3. Connecting Peripherals:

   • Use the digital and analog pins for sensors, actuators, and other peripherals.
   • Ensure all connected devices operate at 3.3V logic levels to avoid damage.

4. Using Communication Interfaces:

   • Use UART, SPI, or I2C for communication with other devices.
   • For audio projects, connect to the I2S pins for digital audio input/output.

• Voltage Levels: The Teensy 4.0 operates at 3.3V logic. Avoid connecting 5V signals directly to the pins.
• Heat Management: The 600 MHz processor can generate heat during intensive tasks. Consider adding a heatsink for prolonged high-performance use.
• Pin Protection: Use resistors or level shifters when interfacing with higher voltage devices to protect the pins.
• Bootloader: The Teensy 4.0 has a built-in bootloader, so no external programmer is required.

The following example demonstrates how to blink an LED connected to pin 13:

// Blink an LED on pin 13 using Teensy 4.0

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

void loop() {
  digitalWrite(13, HIGH); // Turn the LED on
  delay(500);             // Wait for 500 milliseconds
  digitalWrite(13, LOW);  // Turn the LED off
  delay(500);             // Wait for 500 milliseconds
}

1. The board is not recognized by the computer:

   • Ensure the USB cable is a data cable (not a charge-only cable).
   • Check that the Teensyduino add-on is installed correctly.
   • Press the reset button on the Teensy 4.0 to reinitialize the USB connection.

2. Code does not upload:

   • Verify that "Teensy 4.0" is selected as the board in the Arduino IDE.
   • Ensure no other program is using the USB port.
   • Try pressing the reset button before uploading.

3. Peripherals are not working as expected:

   • Double-check the wiring and connections.
   • Ensure all devices operate at 3.3V logic levels.
   • Use pull-up resistors for I2C communication if needed.

4. The board overheats:

   • Avoid running the processor at maximum speed for extended periods without proper cooling.
   • Reduce the clock speed in the Arduino IDE if heat becomes an issue.

• Can I use 5V sensors with the Teensy 4.0?
  No, the Teensy 4.0 operates at 3.3V logic. Use a level shifter to interface with 5V sensors.

• What is the maximum current output of the 3.3V pin?
  The 3.3V pin can supply up to 250 mA, depending on the USB power source.

• Can I use the Teensy 4.0 for audio projects?
  Yes, the Teensy 4.0 is excellent for audio processing. Use the I2S interface for digital audio input/output.

• How do I reset the Teensy 4.0?
  Press the reset button on the board to restart the microcontroller.

This documentation provides a comprehensive guide to using the Teensy 4.0 effectively in your projects. For more advanced features and libraries, refer to the official Teensy website and forums.