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M5Stack Chain Key

M5Stack Chain Key is a single-button input node that adopts a hot-swappable mechanical keyboard design with a blue tactile switch. This key integrates a programmable RGB LED and an STM32G031G8U6 core MCU, and uses a UART serial-cascading communication protocol. Through two HY2.0- 4P expansion interfaces, it can connect more Chain series devices, enabling more complex and interactive applications. The chain key is suitable for human-machine interaction and smart home control scenarios.

Features

  • Single button input
  • STM32G031G8U6 core MCU
  • Hot-swappable mechanical keyboard blue switch
  • 2x RGB LED
  • Uses the UART cascading communication protocol
  • 2x HY2.0-4P expansion interfaces to extend Chain series devices

Kit Contents

  • 1 x Chain key
  • 1 x Chain bridge
  • 1 x Keycap sticker

Applications

  • Smart home control
  • Human-machine interaction

Specifications

  • 5VDC input power
  • UART 115200bps at 8N1 communication method
  • 2x WS2812B RGB LED
  • 28.24mA working power consumption
  • 23.9mm x 23.9mm x 34.4mm product dimension
  • 9.1g weight
  • 138mm x 93mm x 26mm package dimension
  • 14.4g gross weight

Schematic Diagram

Schematic - M5Stack Chain Key

Mechanical Diagram

Mechanical Drawing - M5Stack Chain Key

Additional Resource

Videos

Published: 2026-01-19 | Updated: 2026-01-23