How to Use Cardputer: Examples, Pinouts, and Specs

The Cardputer by M5Stack is a compact computing device that integrates a microcontroller with various input/output (I/O) interfaces. Designed for embedded applications, the Cardputer is ideal for portable or low-power scenarios. Its small form factor and versatile functionality make it a popular choice for developers working on IoT, robotics, and other embedded systems projects.

• Portable IoT devices
• Data logging and monitoring
• Wearable technology
• Robotics control systems
• Educational projects and prototyping
• Low-power computing applications

The Cardputer is built to provide robust performance in a compact package. Below are its key technical specifications:

The Cardputer features a set of GPIO pins and other interfaces for connecting peripherals. Below is the pinout description:

The Cardputer is designed to be user-friendly and versatile. Follow these steps to use it effectively in your projects:

1. Powering the Device:

   • Connect the Cardputer to a USB-C cable for power and programming.
   • Alternatively, use a 3.7V LiPo battery for portable applications.

2. Programming the Cardputer:

   • Install the Arduino IDE or PlatformIO on your computer.
   • Add the ESP32 board support package to your IDE.
   • Select the appropriate board and port in the IDE settings.

3. Connecting Peripherals:

   • Use the GPIO pins to connect sensors, actuators, or other devices.
   • Ensure proper voltage levels to avoid damaging the Cardputer.

Here’s a simple example of how to blink an LED using the Cardputer and Arduino IDE:

// Define the GPIO pin connected to the LED
const int ledPin = GPIO2; // Use GPIO2 for the LED

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

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

  // Turn the LED off
  digitalWrite(ledPin, LOW);
  delay(1000); // Wait for 1 second
}

• Power Supply: Ensure the power source provides sufficient current (at least 500 mA).
• Pin Voltage Levels: The GPIO pins operate at 3.3V. Avoid applying higher voltages.
• Heat Management: While the Cardputer is efficient, prolonged high-load operations may cause slight heating. Ensure proper ventilation if used in enclosed spaces.

1. The Cardputer is not detected by the computer:

   • Ensure the USB-C cable is a data cable, not just a charging cable.
   • Check that the correct COM port is selected in the IDE.
   • Install the necessary USB drivers for the ESP32.

2. The program does not upload to the Cardputer:

   • Press and hold the "Boot" button on the Cardputer while uploading the code.
   • Verify that the correct board and port are selected in the IDE.

3. Wi-Fi or Bluetooth is not working:

   • Ensure the correct credentials or pairing settings are used.
   • Check for interference from other devices.

4. The device is overheating:

   • Reduce the processing load or add a heat sink if necessary.
   • Ensure the device is not exposed to high ambient temperatures.

Q: Can I use the Cardputer with MicroPython?
A: Yes, the Cardputer supports MicroPython. You can flash the MicroPython firmware and use it for development.

Q: What is the maximum current output of the 3V3 pin?
A: The 3V3 pin can supply up to 500 mA, depending on the power source.

Q: Can I connect the Cardputer to an external display?
A: Yes, the Cardputer supports external displays via SPI or I2C interfaces.

Q: Is the Cardputer compatible with Arduino shields?
A: No, the Cardputer does not have a standard Arduino shield form factor. However, you can connect peripherals using jumper wires.

By following this documentation, you can effectively integrate the Cardputer into your projects and troubleshoot common issues. Happy building!