Keyboard

Main menu key: k

Use Cardputer as a USB or BLE HID keyboard / mouse. This App cannot return to the menu with ESC — hold BtnGO.

No header on the main input screen. Left pill column shows Fn / Aa / Opt / Ctrl / Alt; center shows a large last-key echo; footer shows link status, green device name, and a yellow slot badge.

Screenshots

Main / USB / Mouse

Hosts / Special keys

Shortcuts

Mode and exit

Key	Action
Fn + u	USB HID
Fn + b	BLE HID
Hold Fn	Toggle IMU→mouse pointer
Fn + p	BLE host list (switch / pair)
Tap BtnGO	Open / close the BLE host list (same as Fn + p)
Hold BtnGO	Exit to main menu (and disconnect BLE)
Fn + h	Help

IMU mouse (hold Fn)

Letters are used for clicks (not typed). Digits set sensitivity. Other function keys still go to the host.

Key	Action
Left-half letters qwerty asdfg zxcv (ygv left)	Left click
Right-half letters uiop hjkl bnm (uhb right)	Right click
1–9 / 0	Sensitivity 1..10

Center shows a mouse icon; right side is the sensitivity bar. If BLE pointer does nothing, forget the device on the host and re-pair.

Transport and sensitivity are saved under hid_keyboard in config.json and restored the next time the app opens. The IMU mouse toggle is temporary and defaults to off whenever the app opens.

BLE host list (Fn+p / tap BtnGO)

Stores up to 5 paired hosts; only one connected at a time.

Key	Action
1–5 / ; , . /	Select slot
Enter / Space	Switch to that host (disconnect current; on the target, tap Cardputer KB in Bluetooth)
n	New pairing (needs free slot; rejects reconnect from old hosts)
r	Rename current slot alias (Enter saves; empty name shows MAC again; ` cancels)
Backspace	Delete current slot pairing
p / h / tap BtnGO	Close list

Fn layer (Help page 2)

Key	Action
` (bare)	Esc (to host)
Fn + Backspace	Delete
Fn + ; , . /	Arrow keys
Fn + 1–0	F1–F10
Fn + - =	F11 / F12
Fn + A/a	CapsLock
Fn + modifiers	Right-side modifier mapping (see Help)

Usage

1. Use a cable for USB, or Fn+b for BLE keyboard then pair on the host (Fn+p → n).
2. Multiple hosts: Fn+p or a tap on BtnGO opens the list, select a slot, Enter to switch. reconnecting #N means waiting for the target PC to auto-reconnect (usually within a few seconds; otherwise tap Cardputer KB in Bluetooth again).
3. New pairing with n: rejects old hosts grabbing the link, then search/pair on the new PC.
4. Type normal characters directly; bare ` sends Esc; other function keys use the Fn layer.
5. Hold Fn for IMU mouse; ygv left / uhb right click; 1–0 set sensitivity; other function keys still work.
6. Always exit by holding BtnGO (disconnects BLE); a short tap only toggles the host list; ` is Esc to the host.
7. BLE combo keyboard+mouse: after firmware update, forget Cardputer KB and re-pair if the pointer does nothing.