Electronics & Firmware

The control system is built around a Seeed Studio XIAO ESP32-C3 with a TCS34725 color sensor, stepper motor for disc rotation, and a micro servo for the sorting chute.

Core components

• XIAO ESP32-C3 — main controller (I²C, UART, USB-C)
• TCS34725 — RGB color sensor (I²C, SDA/SCL on GPIO6/GPIO7)
• 28BYJ-48 stepper + driver — rotating disc
• SG90 or serial-bus servo — chute / gate actuation
• Limit switch — home position or cycle trigger

Firmware

State machine: idle → detect color → set chute angle → advance disc → release bead. Link Arduino sketch and wiring diagram here (see also Week 16 — system integration).

Wiring

Power servos and stepper from an external 5 V supply; tie grounds with the XIAO. Never power the servo VCC from the XIAO 3.3 V pin.