How to Use Teensy 4.1: Examples, Pinouts, and Specs

The Teensy 4.1 is a high-performance microcontroller development board designed and manufactured by PJRC, often used in the Arduino ecosystem. It is based on the 32-bit ARM Cortex-M7 processor, which provides a significant step up in performance compared to traditional 8-bit microcontrollers. This makes the Teensy 4.1 an excellent choice for advanced projects that require intensive processing power, such as digital audio processing, real-time data analysis, and complex control systems.

Common applications for the Teensy 4.1 include:

• Musical instruments and synthesizers
• Advanced robotics
• Home automation systems
• High-speed USB communication
• Prototyping Internet of Things (IoT) devices

• Processor: ARM Cortex-M7 at 600 MHz
• Flash Memory: 8 MB (64 Mbit)
• RAM: 1 MB
• Voltage (Input): 3.3V to 5V
• Digital I/O Pins: 40 (including 31 PWM capable)
• Analog Inputs: 14 (18-bit ADC)
• Analog Outputs: 2 (12-bit DAC)
• Serial Ports: 7
• I2C Ports: 3
• SPI Ports: 1
• CAN Bus Ports: 2
• USB Host/Device: 1
• Ethernet: 10/100 Mbit (6 pins)
• SD Card Slot: 1 (SDIO capable)

To use the Teensy 4.1 in a circuit:

1. Powering the Board: Connect a 3.3V to 5V power supply to the VIN pin and GND.
2. Programming: Connect the board to a computer using a micro USB cable to upload sketches.
3. Digital I/O: Use the digital pins for input or output by setting their mode in the code.
4. Analog Input: Connect sensors to the analog pins to read varying voltages.
5. Analog Output: Use the DAC pins to output analog signals.
6. Communication: Utilize the serial, I2C, SPI, CAN, or Ethernet pins for communication with other devices.

• Always ensure that the power supply voltage is within the specified range to avoid damaging the board.
• When connecting external components, make sure they are compatible with the board's logic level (3.3V).
• Use proper decoupling capacitors close to the board's power pins to minimize power supply noise.
• Avoid drawing more than 250 mA from the 3.3V onboard regulator.
• For high-speed USB communication, ensure that the USB cable is of good quality and as short as possible.

• Board Not Recognized: Ensure the micro USB cable is properly connected and the computer's USB port is functioning.
• Sketch Not Uploading: Check the selected board and port in the Arduino IDE. Press the reset button on the board and try again.
• Unexpected Behavior: Verify that all connections are secure and that the code uploaded to the board is correct.

• If the board is not recognized, try a different USB cable or port.
• For upload issues, ensure that the correct drivers are installed and that the Teensy Loader application is running.
• Review the code for errors and ensure that the correct libraries are included.

Q: Can I power the Teensy 4.1 with a battery? A: Yes, you can power the Teensy 4.1 with a battery as long as the voltage is within the 3.3V to 5V range.

Q: Is the Teensy 4.1 compatible with all Arduino libraries? A: While many Arduino libraries are compatible, some may need modifications due to the different processor architecture.

Q: How do I use the Ethernet capabilities of the Teensy 4.1? A: To use Ethernet, you will need to solder an Ethernet PHY to the provided pins and use the appropriate library for communication.

The following is a simple example of blinking an LED connected to pin 13 on the Teensy 4.1. This code is compatible with the Arduino IDE.

// Blink an LED connected to pin 13

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

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

Remember to select the correct board (Teensy 4.1) in the Arduino IDE before uploading the code.