34-key split keyboard with 2 TrackPoints and Trackball, using XIAO BLE controllers and a dongle.

• Left side TrackPoint working (Sprintek all-in-one module)
• Standalone PMW3610 trackball working as third peripheral
• Mouse layer auto-activates on trackpoint/trackball movement
• Scroll mode working

Dongle (central) <-- Left (trackpoint) + Right (trackpoint) + Trackball (PMW3610)

With 3 pointing devices streaming mouse data, ESB wins over BLE:

• Lower latency (no BLE connection interval scheduling)
• No BLE bandwidth contention across multiple peripherals
• Deterministic timing for continuous mouse input
• Dongle is USB-only, simplifying the firmware

When moving trackpoint or trackball, the mouse layer auto-activates + 1 second after last movement.

Thumb keys:
| SCROLL | LCLK | LCLK | RCLK |

• Scroll: Hold to convert movement to scroll wheel

• TrackPoint: Still has stability issues with pullup resistors but auto restarts with adjusted trackpoint driver
• Trackball: Uses 3-wire SPI (MOSI/MISO shared on D9)

nix develop
just build all