OpenPuck Config

nRF52840 Steam Controller 2 puck reimplementation — WebUSB. Chrome/Edge only.

disconnected

If nothing appears in the device picker, the copycat may be busy (quit any app holding it) or needs a replug.

USB mode

Switching reboots the copycat and re-enumerates USB (~2 s). WebUSB works in every mode, including Steam/Lizard with Steam running (Chrome claims the vendor interface; Steam keeps the HID slots). Switch HORIPAD + WebUSB is PC-only.

Persist last mode Off (default): every restart / fresh reconnect boots into Steam mode. On: remembers the last mode you selected.

Back4 + face button chords

Hold all four back paddles (L4+R4+L5+R5) plus a face button to switch mode without the WebUI. A is always Steam. B / X / Y are configurable below (defaults: B=Lizard, X=Xbox, Y=Switch HORIPAD).

B + back4 →

X + back4 →

Y + back4 →

Link status

RF link

—

Battery

—

Signal

—

Slot

—

Delivered

—

New reports

—

Polls/s

—

Loop period

—

Slowest stage

—

Poll period act/want

—

Build (git)

—

IMU (raw): —
Raw SC2 accel (before scaling). This controller is a ±2 g sensor (~16384 = 1 g); the Switch report divides it by 4 to present the genuine ±8 g (4096 = 1 g) scale so the console's gravity-correction engages and the gyro stops drifting.

Polls/s ≈ 250 expected; it's capped by Loop period (≈4000 µs needed). "Slowest stage" is the loop section eating the most time per iteration.

If the controller's haptics get stuck/buzzing, this re-inits them (same as pressing Steam).

Fires the controller power-off (0x9F "off!", x3) — the same path Steam's "turn off controller" and host-suspend use. Watch the link status to see it disconnect.

Reboots the puck into serial DFU mode (adafruit-nrfutil). The device drops off USB — flash with adafruit-nrfutil dfu serial … then replug.

Reboots the puck into the UF2 mass-storage bootloader. It mounts as a USB drive — drag the .uf2 file onto it to flash, then it reboots automatically.

Danger: wipes all persistent storage on the copycat — the paired controller bond and every saved setting (mode, chords, back-paddle map, sensitivity). The copycat reboots to factory defaults and you must re-pair the controller. This cannot be undone.

Trackpad mouse (lizard + Xbox)

Sensitivity

Glide / friction

Right-pad cursor in Steam-mode lizard (Steam closed) and in Xbox mode. Sensitivity is a divisor — lower = faster pointer. Glide = how long the cursor coasts after a flick.

Rumble

Strength

Scales rumble amplitude across all modes (100% = native, 200% = double, 0% = off).

Switch Pro motion

Report rate

120 Hz (default) is low-latency and drift-free. 66 Hz is a genuine-cadence compatibility fallback. Full rate (~250 Hz) is lowest-latency but non-genuine — use only if your console tolerates it.

Gyro scale

Gyro sensitivity multiplier for Switch Pro mode (1.0× = unchanged).

Button mapping

A/B + X/Y swap Nintendo layout (affects Xbox & Switch modes)

L4 (back upper-left)

R4 (back upper-right)

L5 (back lower-left)

R5 (back lower-right)

QAM (3 dots)

Back-paddle → button, applied in Xbox & Switch modes. QAM remap applies to all modes (0 = default per-mode behavior).

Capture — host → controller commands

The firmware logs everything from boot into a big RAM ring: Steam's writes (ifN), the frames we transmit to the controller (TX→ctlr), and RF LINK UP/DOWN edges. For the reconnect buzz: trigger it (it appears moments after the puck boots / the controller reconnects), then connect here and click Dump from boot — the trigger is still in the ring. (Only present in a logging build, -DOPK_LOG=1.)

Dump streams the whole ring (oldest→newest) and then keeps live-updating until you press Stop. cmd is the command/report byte, then the raw bytes.