BTXETUEL Sayodevice-O3C 3-key OSU keypad knob screen Black

Compact three-key OSU keypad

The BTXETUEL Sayodevice-O3C is a dedicated mini keyboard built for rhythm gamers who need rapid, precise inputs. Three Hall-effect magnetic linear switches provide adjustable actuation without physical contact. A rotary knob and a 0.96 inch IPS colour screen sit alongside the keys for extra control and live feedback. The unit connects via USB Type-C with a 2.0 interface and polls at 8000 Hz.

Upgrade from standard membrane or mechanical keypads

Magnetic switches eliminate debounce delay and let you set the actuation point to suit each game. The hot-swap sockets accept any compatible Hall magnetic switch, so worn or mismatched switches are replaced in seconds without soldering. Calibration is required on first use or after a firmware update, but the process is guided on screen. The jump is worth it when consistency and per-key tuning matter more than key count.

Behaviour during extended play

The 160 by 80 resolution screen stays legible during long sessions, showing key range, press counts or a custom ID line you define. Hall sensors maintain their feel over millions of presses because there are no metal leaves to fatigue. RGB backlighting runs continuously without affecting the 8000 Hz polling rate. The knob can be mapped to any function, letting you scroll track lists or adjust volume without leaving the keypad.