Cirque Glidepoint trackpad in place of the trackball
Bismuth replaced the trackball with a 23 mm Cirque Glidepoint pad driven by a QT Py RP2040 over I²C, which shows up as a plain USB mouse with no driver work.
What it takes
- Disassembly
- Soldering
- Drilling / permanent
- Purchase required
Difficulty 3 of 3 — advanced.
Details
The trackpad is a 23 mm Cirque Glidepoint (Pinnacle controller, from Mouser) wired over I²C to an Adafruit QT Py RP2040 running CircuitPython with the 2bndy5 CirquePinnacle library, so the console just sees a USB mouse. It sits flush in the trackball opening; 30 AWG wires run through the trackball hole and an extra hole drilled beside the display cable.
Caveats from the thread: an EMI problem made it stop working unless the case was touched (shielded cable suggested), and bare PCB is not the nicest surface, so a cover and bezel STLs were planned. A one-off build with enough detail to copy rather than a kit.
Links
Open at Forum threadRelated mods
lululvlv's replacement keyboard puts a BlackBerry 9900 optical trackpad where the ball was and runs ZMK; sold on Tindie and hack2you.tech since late 2025.
Open-source QMK port of the keyboard firmware: Select + ball scrolls, Fn + G game mode, precision mode, tap-hold keys and a web tester, flashed over USB.
Swap the stock ball for a white BlackBerry ball, the ball from a Pimoroni breakout or a fresh EVQWJN007 module — the usual first fix for a jumpy trackball.
beams' guide revives dead trackballs by roughing the ball on 120-grit paper or fitting a 5.5 mm glass ball, with a printed shim to stop the module rattling.
ClockworkPi's flash tool updates the keyboard's STM32 over the internal USB with dfu-util, no disassembly; the UART route and the S1 pads recover a bricked one.
The 0.1 mm diffuser film dims the backlight; pulling it out brightens the keys, and beams' printed 95A TPU diffuser evens the light and lightens the key feel.