An optimized visual expression system for robots using dual 1.28-inch round LCDs and an RP2040 micro-architecture. This system utilizes partial window refreshes and asynchronous state machines to deliver 60FPS pupil tracking without the latency of procedural pixel rendering.
The firmware architecture focuses on low-latency memory management to maintain visual fluidity:
| Component | Role & Specification |
|---|---|
| Microcontroller | Raspberry Pi Pico (RP2040) @ 133MHz |
| Display Driver | 2x GC9A01 Round LCD (240x240 px / 1.28") |
| Interface | Hardware SPI (Dual-CS Configuration) |
| Color Depth | RGB565 16-bit (Optimized Bit-Depth Assets) |
| Input Protocol | 3.3V UART (Asynchronous Coordinate Stream) |
The system manages two independent round LCDs by multiplexing the MOSI line with discrete Chip Select (CS) logic, ensuring zero-latency synchronization between the left and right eye states.
Designed to replicate biological eye movements. By pairing with the ESP32-CAM FaceTracker, the system utilizes "Saccade Masking"—triggering blinks during rapid gaze shifts to hide artificial pupil "snapping."