Adafruit Grand Central M4 Express Evaluation Board

Adafruit Grand Central M4 Express Evaluation Board is a development tool that evaluates the Microchip ATSAMD5. The board features the SAMD51 microcontroller without headers, resulting in an ultra-thin, lightweight board. The board features a Cortex M4 Core 120MHz Arm® microcontroller with floating-point support. Grand Central has 62x General Purpose Input Output pins. Of those pins, 16x are analog in, and 2x are true analog out. The board also has an SPI port, I2C port, and UART. The board supports CircuitPython or Arduino IDE libraries for wireless integration and building Internet of Things (IoT) projects. The board also includes an 8MB QSPI Flash storage chip.


  • Cortex M4 core running at 120MHz
  • Hardware digital signal processing (DSP) and floating point support
  • 1MB flash, 256KB RAM
  • 32-bit, 3.3V logic and power
  • 70x GPIO pins in total
  • Dual 1 MSPS DAC (A0 and A1)
  • Dual 1 MSPS ADC (15x analog pins)
  • 8x hardware SERCOM (can be I2C, SPI, or UART)
  • 22x PWM outputs
  • Stereo I2S input/output with MCK pin
  • 12-bit parallel capture controller (for camera/video in)
  • Built-in crypto engines with AES (256 bit), true RNG, and Pubkey controller
  • 102.6mm x 53.3mm x 7mm dimensions

Kit Contents

  • Assembled and tested board
  • Loose 2.1mm DC jack and bumpers


Published: 2019-05-23 | Updated: 2023-05-25