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5.2 Input

Keyboard

Your PC keyboard is mapped onto the Spectrum's. Letters, digits, Enter and Space are where you expect; the rest of the Spectrum's oddities are reachable through modifiers:

PC key Spectrum key
Shift (either) Caps Shift
Ctrl (either) Symbol Shift
Backspace Delete
Arrow keys Cursor keys
Esc Break
Tab Extend Mode
Caps Lock Caps Lock
Key left of 1 True Video
\ Inverse Video
Alt + key left of 1 Inverse Video
Alt + E Edit
Alt + G Graph
Alt + C Caps Lock
' ; . , " ; . ,
/ - = / - = (Symbol Shift + V / J / L)
Shift + digit Caps Shift + that digit
Shift + symbol key Caps Shift + that symbol key

Those last two rows are how you reach the Caps Shift layer without hunting for it: Shift+1 is Edit, Shift+2 Caps Lock, Shift+3 True Video, Shift+4 Inverse Video, Shift+5 to Shift+8 the four cursor keys, Shift+9 Graph and Shift+0 Delete. JNEXT keys off the physical key you pressed, not the character your host layout produces for it — the same way the Next's own PS/2 keymap treats the shift keys as a separate overlay. Earlier versions looked at the character instead, so all nineteen shifted digits and symbols were thrown away before the Spectrum saw them.

Three things catch people out:

  • Shift is Caps Shift and Ctrl is Symbol Shift — the same way round as a real Spectrum Next with a PC keyboard plugged into it. Earlier versions had these two swapped. On a Mac the Symbol Shift key is Control (⌃), in the same place as on a PC keyboard; Cmd (⌘) is not a Spectrum key at all, it carries JNEXT's shortcuts (see On a Mac).
  • Esc is Break, not "get me out of fullscreen". Fullscreen is F11 (on a Mac: Control+Command+F, ⌃⌘F, or the green title-bar button, since macOS takes F11).
  • Alt is a host modifier, never a Spectrum key (on a Mac the host modifier is Cmd instead and Option is the Spectrum key). Only the four Alt combinations above are used, because the menu bar and the menu shortcuts claim the rest — and Alt+1 to Alt+8 are the script host keys: they do not type their digit (Alt+9 and Alt+0 still do). Alt+Shift+F5 and Alt+Shift+F9 are Quick Save and Quick Load (5.9 Snapshots).

On a Mac, shortcuts use Command

On macOS every JNEXT shortcut that is Alt + key on the other systems is Cmd + key (⌘), the Mac convention. Wherever this guide says Alt+X for a JNEXT shortcut, press ⌘X; the menus show the Mac form. In particular:

  • ⌘Q quits, and so does ⌘F4 (the Mac form of Alt+F4) and ⌘, opens Settings > Preferences, as in other Mac applications.
  • ⌘1 to ⌘8 are the script host keys, and ⌘⇧F5 and ⌘⇧F9 are Quick Save and Quick Load; ⌘9 and ⌘0 do nothing special.
  • Option (⌥) is the Spectrum's Alt, never a host modifier: Option+E is Edit, Option+G Graph, Option+C Caps Lock, and Option+F1 / Option+F4 do nothing.
  • Control (⌃) is Symbol Shift, so the NextBASIC sequences described below (Ctrl+O ;, Ctrl+D STEP, ...) are Control+letter on a Mac too.
  • A Cmd chord that JNEXT does not use never reaches the program, so Cmd+C does not type a C.
  • The menu-bar mnemonics (Alt+F for the File menu, ...) do not exist on macOS, where the menu bar is the system one. The recording shortcuts, written Ctrl+F5 and Ctrl+F6 below, are ⌃F5 and ⌃F6 there (the Control key, not Command: ⌘F5 belongs to macOS's VoiceOver).

Ctrl belongs to the program you are running. No Ctrl+letter chord of any kind is a JNEXT shortcut, so the Symbol Shift sequences NextBASIC leans on — Ctrl+O ;, Ctrl+D STEP, Ctrl+R <, Ctrl+T >, Ctrl+Q <=, Ctrl+S | — all reach the guest, and so does Ctrl+Shift+S (Caps Shift + Symbol Shift + S). Earlier versions bound those to menu commands, which meant the program never saw them (and Ctrl+Q quit JNEXT outright). They live on Alt now: Save Snapshot, the last one to move, is Alt+Shift+S. The only Ctrl chords JNEXT still takes are Ctrl+F5 and Ctrl+F6 (start and stop video recording), and function keys have no Spectrum meaning to lose.

On real Next hardware Left Alt is Extend Mode and Right Alt is Graph. JNEXT does not do that: Alt is reserved for the host, and Extend Mode is on Tab — the same convention FUSE and ZEsarUX use. That is a deliberate trade, made so that Ctrl could be given back to the guest.

Tapping Alt on its own does nothing, and that is on purpose. In most applications a bare Alt press-and-release moves the keyboard into the menu bar, so the next letter you type opens a menu instead of typing. JNEXT turns that off (decided 2026-09-25): here Alt is simultaneously a key the guest needs — Alt+E, Alt+G, Alt+C — and the modifier every JNEXT shortcut lives on, so a stray Alt while typing used to hand the keyboard to the menu bar with nothing on screen to say so, and the next letter vanished into it. The menus are still fully reachable from the keyboard: Alt+F, Alt+M, Alt+I, Alt+A, Alt+B, Alt+V, Alt+N and Alt+H open File, Machine, Input, Tape, Debug, View, Settings and Help, and the arrow keys work inside them as usual. Only the tap-Alt-then-arrow route is gone.

The machine's own front-panel keys are on function keys: F1 hard reset, F4 soft reset, F9 Multiface NMI, F10 DivMMC. (With the debugger open, F9 belongs to the debugger.) With Alt held, F1 and F4 never reset the machine: Alt+F4 quits JNEXT. It is the second shortcut of File > Quit, next to Alt+Q, and it works whatever else is held and with the mouse captured or not. Alt+F1 does nothing. With Alt and Shift held, F5 and F9 are the quick snapshot keys instead and reach neither the Multiface nor the guest. The Pause key pauses and resumes the machine (Machine > Pause, also Alt+U). The two resets are also in the Machine menu and on the toolbar: Power Reset (Alt+R, same as F1) is a power off/on cold boot that re-runs the whole boot chain; Soft Reset (same as F4) is the front-panel reset button — it returns to NextZXOS without re-running the boot chain. Soft Reset does nothing while the firmware is still booting. After a direct --load it resets into 48K BASIC and discards the program you loaded: that boot never ran the firmware, so there is no NextZXOS to come back to — use Power Reset there.

Joysticks and gamepads

USB gamepads are picked up automatically, hot-plug included, and wired to the Next's two joystick connectors: the first two to connect become Joy 1 and Joy 2. The joystick protocol — Kempston, Sinclair, Cursor or MD — is chosen by the software you are running, just as on real hardware, so a game that expects Kempston gets Kempston without you configuring anything.

Choosing the controller for each connector

Input > Joy 1 Source and Joy 2 Source (and Settings > Preferences > Input) list, for each connector:

  • Automatic (first free controller) — the default: the behaviour above;
  • every controller currently connected, by name (two identical pads show as name and name #2);
  • Cursor Keys + Space, below;
  • None — nothing drives the connector.

A pick applies at once, without a restart, and is remembered by the controller's identity rather than its position, so it survives unplugging, plugging back in and restarting. If a remembered controller is not connected, the menu shows it as name (not connected), the connector uses the first free controller in the meantime (jnext logs that) and takes the remembered one back as soon as it appears. One controller cannot drive both connectors: picking it for one takes it from the other, which goes back to Automatic. With two identical pads the #2 numbering holds only while they are connected in the same order. Unplugging a controller lets go of any button it was holding.

From the command line, --joy1-device ID / --joy2-device ID choose a controller for one run; the id is the one in the log line Joystick 1 connected: 'name' [id], and --joy1-source none / --joy2-source none leave a connector unused.

With no gamepad, point a connector at the host cursor keys instead: arrows to move, Space to fire. Choose it in the Input menu, in Settings > Preferences > Input, or with --joy1-source keys / --joy2-source keys; the choice is remembered.

Only one connector can use the cursor keys at a time, and while it does, the arrows and Space stop working as ZX keys.

Mouse

For software that uses a Kempston mouse, JNEXT has to confine your pointer — otherwise it hits the edge of your screen and the emulated pointer stops.

  • Capture: click the emulator screen, or use Input > Capture Mouse.
  • Release: Ctrl+Alt (Alt+Cmd on a Mac) by default, the same combination VirtualBox and QEMU use. You can choose a middle click or Esc instead in Settings > Preferences > Input, or with --mouse-release (ctrl-alt, middle-click or esc). Only the chosen gesture releases. With Esc, Esc stops being BREAK while the mouse is captured (it is BREAK again once released); with middle click, the middle button no longer reaches the program. Either way the click or key that releases is not passed to the program.

Capture is off until you ask for it, so the pointer stays yours and you can always reach the menus. While captured, the status bar reminds you how to get out. The click that captures is not passed through to the program.