Notes for GPIO

../_images/picow-1.png

GPIO Overview

The Raspberry Pi Pico W has 26 multi-function GPIO pins (GP0 to GP28, with some numbers not used). All GPIO pins can be assigned various functions, including digital input, digital output, and up to 8 different alternate functions such as UART, I2C, SPI, PWM, etc.

By default, all GPIO pins are configured as digital inputs with pull-down enabled when the Pico W powers up or resets.

Note

GPIO pins on the Pico W operate at 3.3V. They are NOT 5V tolerant, and connecting them to 5V may damage your board.

Special Function Pins

Some GPIO pins have special default functions on the Pico W:

  • LED Pin: GP25 is connected to the onboard LED

  • UART0: GP0 (TX) and GP1 (RX) are the default UART pins

  • I2C0: GP4 (SDA) and GP5 (SCL) are the default I2C pins

  • SPI0: GP16-19 are used for the onboard wireless chip (CYW43439)

  • USB: GP24 (D-) and GP25 (D+) are used for USB communication

../_images/picow_pin.png

For detailed information about GPIO functionality, please refer to the official Raspberry Pi Pico W Technical Documentation: https://www.raspberrypi.com/documentation/microcontrollers/pico-series.html#picow-technical-specification

Or you can click on the links below: