fuse(1)

✨ NAME ✨

okay so bestie, meet fuse(1) — she's a Sinclair ZX Spectrum emulator and she's literally iconic. 👑💅

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🌸 SYNOPSIS 🌸

fuse [options]

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🦋 DESCRIPTION 🦋

Fuse is a Sinclair ZX Spectrum emulator. It supports several models (including the 128), with quite faithful emulation of the display and sound. 💖

The emulator can load any of the formats supported by libspectrum(3) — this includes Z80, SNA and SZX snapshots, and PZX, TAP and TZX virtual-tape files. Saving to SZX, Z80 and SNA snapshots and TZX and TAP tape files is supported. The SLT extension to the Z80 format is partly supported (enough for multi-load games); however, loading of the old DAT-file variant is not. 😭

DSK, UDI, FDI, TD0, MGT, IMG, D40, D80, SAD, TRD, SCL and OPD disk images are supported when a disk interface is being emulated, including the integrated disk drives on +3, Pentagon or Scorpion machines as well as the +D, DISCiPLE, Opus Discovery, Beta 128 and Didaktik 80 interfaces. DCK cartridge images are supported when emulating a Timex 2068 variant. Interface 2 ROM cartridges are also supported. ✨

Finally, there is also support for reading and writing the RZX input recording format. 🎀

See the COMPRESSED FILES section for details on reading files compressed with bzip2(3), gzip(3) or zip(3). 🦋

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👑 OPTIONS 👑

okay so here's the whole lineup, bestie. Every flag, every default, every vibe. 💅

• --accelerate-loader — Specify whether Fuse should attempt to accelerate tape loaders by “short circuiting” the loading loop. This will in general speed up loading, but may cause some loaders to fail. (Enabled by default, but you can use --no-accelerate-loader to disable). The same as the Media Options dialog's Accelerate loaders option.
• --aspect-hint — Specify whether the Xlib user interface should hint to the window manager about the preferred aspect ratio for the graphics window, thus preventing resizing to non-square sizes which lead to Fuse not displaying correctly. (Enabled by default, but you can use --no-aspect-hint to disable).
• --autosave-settings — Specify whether Fuse's current settings should be automatically saved on exit. The same as the General Options dialog's Auto-save settings option.
• --auto-load — Specify whether tape and disk files should be automatically loaded when they are opened using the File, Open... menu option. In the case of TRD/SCL disk images, inserts also a boot loader file when none is available. (Enabled by default, but you can use --no-auto-load to disable). Same as the Media Options dialog's Auto-load media option.
• --beta128 — Emulate a Beta 128 interface. Same as the Disk Peripherals Options dialog's Beta 128 interface option.
• --beta128-48boot — When a Beta 128 interface is used in 48K or TC2048 emulation the option additionally controls whether the machine boots directly into the TR-DOS system. Same as the Disk Peripherals Options dialog's Beta 128 auto-boot in 48K machines option.
• --betadisk file — Insert the specified file into the emulated Beta disk interface's drive A: and select Pentagon mode on startup.
• --bw-tv — Specify whether the display should simulate a colour or black and white television. This option is effective under the GTK, Win32, Xlib and SDL user interfaces: the others will always simulate a colour TV. The same as the General Options dialog's Black and white TV option.
• --cmos-z80 — This option specifies that Fuse should emulate a CMOS Z80, as opposed to an NMOS Z80. Same as the General Options dialog's Z80 is CMOS option.
• --competition-code code — Specify the code to be written to competition mode RZX files. The same as the RZX Options dialog's Competition code option.
• --competition-mode — Specify whether input recordings should be made in competition mode. The same as the RZX Options dialog's Competition mode option.
• --composite-filter-artifacts value — sets the Artifacts control.
• --composite-filter-bleed value — sets the Bleed control.
• --composite-filter-brightness value — sets the Brightness control.
• --composite-filter-contrast value — sets the Contrast control.
• --composite-filter-fringing value — sets the Fringing control.
• --composite-filter-gamma value — sets the Gamma control.
• --composite-filter-hue value — sets the Hue control.
• --composite-filter-resolution value — sets the Resolution control.
• --composite-filter-saturation value — sets the Saturation control.
• --composite-filter-sharpness value — sets the Sharpness control.

All ten of those set the tuning parameters used by the PAL TV and NTSC TV composite filters. Each value is an integer in the range -100 to 100. In that exact order, they correspond to the Filter Options dialog's Artifacts, Bleed, Brightness, Contrast, Fringing, Gamma, Hue, Resolution, Saturation and Sharpness controls respectively.

• --compress-rzx — Specify whether RZX files should be written out compressed. (Enabled by default, but you can use --no-compress-rzx to disable). Same as the RZX Options dialog's Compress RZX data option.
• --confirm-actions — Specify whether dangerous actions (those which could cause data loss, for example resetting the Spectrum) require confirmation before occurring. (Enabled by default, but you can use --no-confirm-actions to disable). This option is the same as the General Options dialog's Confirm actions option.
• --covox — Emulate a Covox sound interface for Pentagon/Scorpion. Same as the Sound Peripherals Options dialog's Covox option.
• --debugger-command string — Specify a debugger command to be run before emulator startup. This can be used to set breakpoints or the like. Currently, this is the only method to input multi-line debugger commands. (See the MONITOR/DEBUGGER section for more information).
• --detect-loader — Specify whether Fuse should attempt to detect when the tape is being accessed and start and stop the virtual tape playing automatically. (Enabled by default, but you can use --no-detect-loader to disable). Same as the Media Options dialog's Detect loaders option.
• --disciple — Emulate a DISCiPLE interface. Same as the Disk Peripherals Options dialog's DISCiPLE interface option.
• --discipledisk file — Insert the specified file into the emulated DISCiPLE's drive 1.
• --didaktik80 — Emulate a Didaktik 80 (or Didaktik 40) disk interface. Same as the Disk Peripherals Options dialog's Didaktik 80 interface option.
• --didaktik80disk file — Insert the specified file into the emulated Didaktik 80 (or Didaktik 40)'s drive A.
• --disk-ask-merge — Prompt the user to confirm whether Fuse should try to merge the B side of a disk image from a separate file when opening a new single-sided disk image.
• --disk-try-merge mode — Select whether Fuse should try to merge a separate file for the B side of a disk image separate file when opening a new disk image. Most double sided disk images are dumped as two single sided disk images e.g. Golden Axe - Side A.dsk and Golden Axe - Side B.dsk. So, if we want to play Golden Axe, first we have to insert the first disk image and when the game asks to insert side B, we have to find and open the second disk image, instead of just flip-ing the disk inside the drive. If enabled, Fuse will try to open the second image too and create a double sided disk image (merging the two one sided disk images) and insert this merged virtual disk into the disk drive. The function detects whether the file is one side of a double-sided image if the filename matches a pattern like [Ss]ide[ _][abAB12][ _.] in the file name of a disk that is being opened. If found, Fuse will try to open the other side of the disk too substituting the appropriate characters in the filename e.g. 1→2, a→b, A→B. If successful then it will merge the two images and now we have a double sided disk in drive. This means that if we open Golden Axe - Side A.dsk, then Fuse will try to open Golden Axe - Side B.dsk too. Now, we can just flip the disk if Golden Axe asks for Side B. The available options are Never, With single-sided drives and Always.
• --divide — Emulate the DivIDE interface. The same as the Disk Peripherals Options dialog's DivIDE interface option.
• --divide-masterfile file — Specify an IDE image to be loaded into the DivIDE's emulated master drive.
• --divide-slavefile file — Specify an IDE image to be loaded into the DivIDE's emulated slave drive.
• --divide-write-protect — Specify that the emulated DivIDE's write protect jumper should be considered set. The same as the Disk Peripherals Options dialog's DivIDE write protect option.
• --divmmc — Emulate the DivMMC interface. The same as the Disk Peripherals Options dialog's DivMMC interface option.
• --divmmc-file file — Specify an HDF image to be loaded into the DivMMC's emulated memory card.
• --divmmc-write-protect — Specify that the emulated DivMMC's write protect jumper that protects EEPROM should be considered set. The same as the Disk Peripherals Options dialog's DivMMC write protect option.
• --dock file — Insert the specified file into the emulated Timex 2068 variant dock; also select the TC2068 on startup if available.
• -D mode, --doublescan-mode mode — Specify whether to use doublescan modes in the FB UI. Available values for mode are 0, 1 and 2. 0 means never doublescan (use 640×480 at either 72 Hz or 60 Hz), whereas 1 and 2 both mean try to use doublescan and will fall back on the 640×480 modes. 1 selects 72 Hz modes (the same size and shape as your typical 640×480), and 2 selects 60 Hz modes (overscan).

If your monitor displays a blank screen when using 1 or 2, press F10 then try a different option or say --fbmode 640.

• --drive-plus3a-type type, --drive-plus3b-type type, --drive-beta128a-type type, --drive-beta128b-type type, --drive-beta128c-type type, --drive-beta128d-type type, --drive-plusd1-type type, --drive-plusd2-type type, --drive-didaktik80a-type type, --drive-didaktik80b-type type, --drive-disciple1-type type, --drive-disciple2-type type, --drive-opus1-type type, --drive-opus2-type type — bestie this one lets you pick which kind of disk drive gets emulated for whichever interface you picked. Your choices are Disabled, Single-sided 40 track, Double-sided 40 track, Single-sided 80 track and Double-sided 80 track. Want the full tea? Peep the Disk Options dialog. And heads up, no cap: Disabled is not supported for Drive 1 or Drive A of any interface, like it's literally just not an option there. 💾
• --drive-40-max-track count, --drive-80-max-track count — set the maximum number of tracks for 40 and 80 track physical drives respectively. That's it, that's the vibe. 🎯
• --embed-snapshot — should a snapshot get embedded in an RZX file when you start recording from an existing snapshot? This decides it. (Enabled by default, but you can use --no-embed-snapshot to disable). Same as the RZX Options dialog's Always embed snapshot option. 📸
• --fastload — should Fuse go zoom-zoom maximum speed while the virtual tape is playing? (Enabled by default, but you can use --no-fastload to disable). Same as the Media Options dialog's Fastloading option. ⚡
• -v mode, --fbmode mode — picks which mode the FB UI runs in. The values for mode are 320 (which corresponds to a 320×240×256 mode), which is the default, and 640 (a 640×480×256 mode). 🖥️
• --fuller — emulate a Fuller Box interface. Same as the Sound Peripherals Options dialog's Fuller Box option. 🔊
• --full-screen — should Fuse run in full screen mode? This option is effective under the GTK, SDL and SDL2 UIs.

Under SDL2, Fuse uses desktop fullscreen: the current desktop display mode is kept and Fuse scales the emulated display to fit it. ✨

• --sdl-fullscreen-mode mode — choose the fullscreen display mode used under the SDL UI. Real talk though: this option has no effect under SDL2, because SDL2 uses desktop fullscreen. mode may be one of the following:
  • list — print the available fullscreen modes and exit. 👀
  • number — select one of the listed fullscreen modes by its number.
  • WxH — select a fullscreen mode by width and height, for example 1024x768.
• -g filter, --graphics-filter mode — which graphics filter to use, if it's available. Default is normal, which uses no filtering at all (the "I woke up like this" option 💅). The available options are 2x, 2xsai, 3x, 4x, advmame2x, advmame3x, dotmatrix, half, halfskip, hq2x, hq3x, hq4x, normal, super2xsai, supereagle, timex15x, timex2x, timextv, tv2x, tv3x, tv4x, paltv2x, paltv3x, paltv4x, ntsctv2x, ntsctv3x, and ntsctv4x. See the GRAPHICS FILTERS section for more details. 🌈
• --graphicsfile file — sets the filename used for graphical output from the emulated ZX Printer. See the PRINTER EMULATION section for more details. 🖨️
• -h, --help — give brief usage help, listing available options. The classic "help meee" button, and honestly same. 🆘
• --if2cart file — insert the specified file into the emulated Interface 2. 🎮
• --interface1 — emulate a Sinclair Interface 1. Same as the General Peripherals Options dialog's Interface 1 option.
• --interface2 — emulate a Sinclair Interface 2. (Enabled by default, but you can use --no-interface2 to disable). Same as the General Peripherals Options dialog's Interface 2 option.
• --issue2 — emulate an issue 2 keyboard. Same as the General Options dialog's Issue 2 keyboard option. ⌨️
• --joystick-1-output type, --joystick-2-output type, --joystick-keyboard-output type — pick which joystick interface gets attached for the first two real joysticks and the keyboard joystick. Default is 0, which is no output. The available options are 1 (cursor), 2 (kempston), 3 (Sinclair 1), 4 (Sinclair 2), 5 (Timex 1), 6 (Timex 2), and 7 (Fuller). Same as the Joysticks Options dialog's Joystick type option. 🕹️
• --joystick-1-fire-1 code, --joystick-1-fire-2 code, --joystick-1-fire-3 code, --joystick-1-fire-4 code, --joystick-1-fire-5 code, --joystick-1-fire-6 code, --joystick-1-fire-7 code, --joystick-1-fire-8 code, --joystick-1-fire-9 code, --joystick-1-fire-10 code, --joystick-1-fire-11 code, --joystick-1-fire-12 code, --joystick-1-fire-13 code, --joystick-1-fire-14 code, --joystick-1-fire-15 code, --joystick-2-fire-1 code, --joystick-2-fire-2 code, --joystick-2-fire-3 code, --joystick-2-fire-4 code, --joystick-2-fire-5 code, --joystick-2-fire-6 code, --joystick-2-fire-7 code, --joystick-2-fire-8 code, --joystick-2-fire-9 code, --joystick-2-fire-10 code, --joystick-2-fire-11 code, --joystick-2-fire-12 code, --joystick-2-fire-13 code, --joystick-2-fire-14 code, --joystick-2-fire-15 code — pick which Fuse key code should be triggered when you press the applicable real joystick button. The codes are the Fuse keyboard codes corresponding to the keys. Default value is 4096, which corresponds to the virtual joystick fire button (yes, the little default that could 🔥). Same as the Joysticks Options dialog's Joystick fire options.
• --joystick-keyboard-up code, --joystick-keyboard-down code, --joystick-keyboard-left code, --joystick-keyboard-right code, --joystick-keyboard-fire code — pick which Fuse key code lines up with each direction and fire for the keyboard virtual joystick. Same as the Keyboard Joysticks Options dialog's Button for UP, Button for DOWN, Button for LEFT, Button for RIGHT and Button for FIRE options respectively. ⬆️⬇️⬅️➡️
• --joystick-prompt — if you pass this, Fuse will ask you which form of joystick emulation you want when a snapshot loads. No prompt gets issued if the config baked into the snapshot already matches what you're currently using. Same as the General Options dialog's Snap joystick prompt option. 🤔
• --kempston — emulate a Kempston joystick. Same as the General Peripherals Options dialog's Kempston joystick option.
• --kempston-mouse — emulate a Kempston mouse. Same as the General Peripherals Options dialog's Kempston mouse option. 🐭
• --keyboard-arrows-shifted — treat the keyboard arrow keys as shifted, like the ZX Spectrum+ keyboard's arrow keys do, or as unshifted like a cursor joystick that maps to the 5, 6, 7 and 8 keys. (Enabled by default, but you can use --no-keyboard-arrows-shifted to disable). Same as the General Peripherals Options dialog's Use shift with arrow keys option. 🌸
• --late-timings — so some real Spectrums have been observed running such that the screen renders one tstate later than on other real hardware, and this option says Fuse should emulate such a machine. Same as the General Options dialog's Late timings option. ⏰
• --loading-sound — should the sound made while tapes are loading be emulated? (Enabled by default, but you can use --no-loading-sound to disable). Same as the Sound Options dialog's Loading sound option. 🎧
• -m type, --machine type — pick the machine type to emulate initially. Default is 48, a 48K Spectrum. The available options are 16, 48, 48_ntsc, 128, plus2, plus2a, plus3, 2048, 2068, ts2068, pentagon, pentagon512, pentagon1024, scorpion and se. The whole squad of Spectrums, iconic honestly. 👑
• --melodik — emulate a Melodik AY interface for 16/48k Spectrums. Same as the Sound Peripherals Options dialog's Melodik option. 🎵
• --mdr-len length — controls the number of blocks in a new Microdrive cartridge. Same as the Media Options dialog's MDR cartridge len option. 📼
• --mdr-random-len — if this is set, Fuse uses a random Microdrive cartridge length. Same as the Media Options dialog's Random length MDR cartridge option. 🎲
• --microdrive-file file, --microdrive-2-file file, --microdrive-3-file file, --microdrive-4-file file, --microdrive-5-file file, --microdrive-6-file file, --microdrive-7-file file, --microdrive-8-file file — name the Interface 1 Microdrive cartridge files to open. 🦋
• --mouse-swap-buttons — swap the left and right mouse buttons when emulating the Kempston mouse. Same as the General Peripherals dialog's Swap mouse buttons option.
• --movie-compr level — sets the compression level used when creating movies. Same as the Movie Options dialog's Movie compression option. The available options are None, Lossless, and High (lossy). Default is Lossless. See also the MOVIE RECORDING section. 🎬
• --movie-start file — with this command line option, Fuse starts movie recording as soon as the emulator starts. See also the MOVIE RECORDING section. 🔴
• --movie-stop-after-rzx — with this one, Fuse stops movie recording when RZX playback or RZX recording ends. Same as the Movie Options dialog's Stop recording after RZX ends option. (Enabled by default, but you can use --no-movie-stop-after-rzx to disable). See also the MOVIE RECORDING section. ✂️
• --multiface1 — emulate a Romantic Robot Multiface One interface. Same as the General Peripherals Options dialog's Multiface One option. 🎀
• --multiface128 — emulate a Romantic Robot Multiface 128 interface. Same as the General Peripherals Options dialog's Multiface 128 option.
• --multiface3 — emulate a Romantic Robot Multiface 3 interface. Same as the General Peripherals Options dialog's Multiface 3 option.
• --multiface1-stealth — sets Multiface One stealth/invisible mode. Same as the General Peripherals Options dialog's Stealth Multiface One option. 🥷
• --opus — emulate an Opus Discovery interface. Same as the Disk Peripherals Options dialog's Opus Discovery interface option. 💜
• --opusdisk file — insert the specified file into the emulated Opus Discovery's drive 1. 🫶

and bestie we are so not done, the options keep coming 💅

• --phantom-typist-mode mode — ok so when a program is loading, there's a lil "phantom typist" that types stuff for you, and this sets the keystroke sequence it uses. Your choices are Auto, Keyword, Keystroke, Menu, Plus 2A and Plus 3. Literally the same thing as the Media Options dialog's Phantom typist mode option 💅
• -p file, --playback file — give it an RZX file and it starts playing it back. that's it, that's the whole vibe 🎬
• --plus3disk file — drops the file you name into the emulated +3's A: drive, and (if it's available) it'll also pick the +3 for you on startup. chef's kiss 🫶
• --plus3-detect-speedlock — decides whether the +3 drives go hunting for Speedlock-protected disks and emulate those weak sectors. BUT — if the disk image file (EDSK or UDI) already has weak sector data in it, then Speedlock detection is automatically omitted, no takebacks. Peep the WEAK DISK DATA section too. Same as the Disk Options dialog's +3 Detect Speedlock option ✨
• --plusd — emulate a +D interface. Same as the Disk Peripherals Options dialog's +D interface option 🎀
• --plusddisk file — insert the file into the emulated +D's drive 1.
• --printer — says whether the emulation should include a printer or not. Same as the General Peripherals Options dialog's Emulate printers option 🖨️
• --rate frame — sets the frame rate, aka the ratio of spectrum frame updates to real frame updates. Same as the General Options dialog's Frame rate option.
• -r file, --record file — hand it an RZX file and Fuse starts recording into it. go off, capture the moment 📼
• --recreated-spectrum — turns on using a Recreated ZX Spectrum in Layer A (game) mode. It's a Bluetooth keyboard you pair to whatever device Fuse is running on. The same as the General Options dialog's Recreated ZX Spectrum option 🔥
• --rom-16 file
• --rom-48 file
• --rom-128-0 file
• --rom-128-1 file
• --rom-plus2-0 file
• --rom-plus2-1 file
• --rom-plus2a-0 file
• --rom-plus2a-1 file
• --rom-plus2a-2 file
• --rom-plus2a-3 file
• --rom-plus3-0 file
• --rom-plus3-1 file
• --rom-plus3-2 file
• --rom-plus3-3 file
• --rom-plus3e-0 file
• --rom-plus3e-1 file
• --rom-plus3e-2 file
• --rom-plus3e-3 file
• --rom-tc2048 file
• --rom-tc2068-0 file
• --rom-tc2068-1 file
• --rom-ts2068-0 file
• --rom-ts2068-1 file
• --rom-pentagon-0 file
• --rom-pentagon-1 file
• --rom-pentagon-2 file
• --rom-pentagon512-0 file
• --rom-pentagon512-1 file
• --rom-pentagon512-2 file
• --rom-pentagon512-3 file
• --rom-pentagon1024-0 file
• --rom-pentagon1024-1 file
• --rom-pentagon1024-2 file
• --rom-pentagon1024-3 file
• --rom-scorpion-0 file
• --rom-scorpion-1 file
• --rom-scorpion-2 file
• --rom-scorpion-3 file
• --rom-spec-se-0 file
• --rom-spec-se-1 file

— these tell Fuse which file to use for the ROM(s) of each machine. Matching them up one by one, bestie: the 16K Spectrum (48.rom), the 48K Spectrum (48.rom), the two ROMs for the 128K Spectrum (128-0.rom and 128-1.rom), the two ROMs for the +2 (plus2-0.rom and plus2-1.rom), the four ROMs for the +2A (plus3-0.rom, plus3-1.rom, plus3-2.rom and plus3-3.rom), the four ROMs for the +3 (plus3-0.rom, plus3-1.rom, plus3-2.rom and plus3-3.rom), the four enhanced ROMs for the +3e (plus3e-0.rom, plus3e-1.rom, plus3e-2.rom and plus3e-3.rom), the TC2048 ROM (tc2048.rom), the two ROMs for the TC2068 (tc2068-0.rom and tc2068-1.rom), the two ROMs for the TS2068 (tc2068-0.rom and tc2068-1.rom), the two main ROMs and the TR-DOS ROM for the Pentagon 128K (128p-0.rom, 128p-1.rom and trdos.rom), the two main ROMs, the TR-DOS ROM and a reset service ROM for the Pentagon 512K and 1024K (128p-0.rom, 128p-1.rom, trdos.rom and gluck.rom), the four ROMs for the Scorpion 256 (256s-0.rom, 256s-1.rom, 256s-2.rom and 256s-3.rom), and the two ROMs for the Spectrum SE (se-0.rom and se-1.rom).

The names in brackets are the defaults, ok? And heads up — not all these ROMs are supplied with Fuse; you have to bring your own copies of the ones that aren't 😭

• --rom-interface-1 file
• --rom-beta128 file
• --rom-plusd file
• --rom-didaktik80 file
• --rom-disciple file
• --rom-multiface1 file
• --rom-multiface128 file
• --rom-multiface3 file
• --rom-opus file
• --rom-sp0256 file
• --rom-speccyboot file
• --rom-ttx2000s file
• --rom-usource file
• --rom-uspeech file

— same deal but for each peripheral's ROM(s). In order: the Interface 1 ROM (if1-2.rom), the TR-DOS ROM for Beta 128 emulation with the 48K, TC2048, 128K or +2 (trdos.rom), the +D ROM (plusd.rom), the Didaktik 80 ROM (didaktik80.rom), the DISCiPLE ROM (disciple.rom), the Multiface One ROM (mf1.rom), the Multiface 128 ROM (mf128.rom), the Multiface 3 ROM (mf3.rom), the Opus Discovery ROM (opus.rom), the SpeccyBoot ROM (speccyboot-1.4.rom), the SP0256 ROM (sp0256-al2.rom), the TTX2000S ROM (ttx2000s.rom), and the µSource ROM (usource.rom), the µSpeech ROM (uspeech.rom).

Again — names in brackets = defaults. And again, not all these ROMs ship with Fuse; the ones that don't, you supply yourself 🫡

• --no-rs232-handshake — makes Fuse's Interface 1 emulation assume the other end of the RS-232 line is live the moment you connect the communication channels. Check the --rs232-rx and --rs232-tx options too 👀
• --rs232-rx
• --rs232-tx

— these set the communication channels (FIFO or file) used for Interface 1 RS-232 emulation, as the RxD and TxD wire respectively. See also the --rs232-handshake options 🔌

• --rzx-autosaves — says that while recording an RZX file, Fuse should automatically drop a snapshot into the recording stream every 5 seconds. (Default to on, but you can use --no-rzx-autosaves to disable it.) Same as the RZX Options dialog's Create autosaves option — go read there if you want the deets 💾
• --sdl-fullscreen-mode mode — picks a screen resolution for full screen mode under the SDL UI. The available values for mode are listed in a table when Fuse is called with the --sdl-fullscreen-mode list command line option. Under SDL2 this does nothing at all, since SDL2 uses desktop fullscreen. 💀
• --separation type — gives the stereo separation of the 128's AY sound channels. Same as the General Options dialog's AY stereo separation option. Available options are None, ACB, and ABC. The default option is None 🎧
• --simpleide — says whether Fuse will emulate the simple 8-bit IDE interface, the one the Spectrum +3e uses. Same as the Disk Peripherals Options dialog's Simple 8-bit IDE option.
• --simpleide-masterfile file — names a HDF file to hook up to the emulated Simple 8-bit IDE interface's master channel.
• --simpleide-slavefile file — names a HDF file to hook up to the emulated Simple 8-bit IDE interface's slave channel.
• --slt — support the SLT trap instruction. (Enabled by default, but you can use --no-slt to disable it.) Same as the Media Options dialog's Use .slt traps option ✨
• -s file, --snapshot file — names a snapshot file to load. It can be in any snapshot format supported by libspectrum(3). 📸
• --sound — says whether Fuse should produce sound. (Enabled by default, but you can use --no-sound to disable it.) Same as the Sound Options dialog's Sound enabled option 🔊
• -d device, --sound-device device — names the sound output device to use, plus any options you wanna hand to that device. If you're not using the SDL UI, or you're using libao or libasound (ALSA) for sound output, then the device parameter just says which device to use for sound output. Simple!

If you're using the SDL UI, device lets you name the audio driver to be used (e.g. dsp, alsa, dma, esd and arts).

If you're using libao for sound output, device lets you name the device used for sound output (either live to a speaker, or to a file) and the parameters for that device. Broadly, the device parameter looks like:

driver[:param[=value][,param[=value][,...]]

driver picks the libao driver — either one of the live drivers (aixs, alsa, alsa09, arts, esd, irix, macosx, nas, oss or sun) or a file driver (au, raw, wav or null). And here are the param/value pairs you can use for each device 👇

• aixs: AIX audio system
  • dev=device — device gives the AIX sound device.
• alsa: Advanced Linux Sound Architecture version 0.5.x
  • card=num — num gives the ALSA card number.
  • dev=num — num gives the ALSA device number.
  • buf_size=num — num gives the ALSA buffer size in bytes.
• alsa09: Advanced Linux Sound Architecture version 0.9+
  • dev=string — string specifies the ALSA device, e.g. hw:1.2
  • buffer_time=num — num gives the ALSA buffer time in microseconds.
  • period_time=num — num gives the ALSA period time in microseconds.
  • use_mmap=yes|y|true|t|1 — specifies that libao use memory mapped transfer.
• arts: aRts soundserver: no parameters.
• esd: Enlightened Sound Daemon.
  • host=string — string gives the ESD host specification.
• irix: IRIX Audio Library: no parameters.
• macosx: MacOS X CoreAudio: no parameters.
• nas: Network Audio System.
  • host=string — string gives the NAS host specification.
  • buf_size=num — num gives the buffer size on the server.
• oss: Open Sound System.
  • dsp=string — string gives the OSS device to be used, e.g. /dev/sound/dsp1
• sun: SUN audio system.
  • dev=string — string gives the audio device to be used.

• au — SUN Sparc audio file, and it takes, like, zero parameters. None. Not a one. 💅
  • raw — raw file. Just raw vibes.
    • byteorder=string — and string can be any of native (aka whatever byteorder your host is rocking natively), big (big endian bestie) or little (little endian ✨).
  • wav — Microsoft audio file: no parameters, no notes, no drama.
  • null — null output: no parameters. It's giving absolutely nothing, on purpose.
  • debug — for debugging libao. For when libao is acting up and you need answers. 🔍

Okay so listen 👑 — every single one of the file output types (au, raw and wav) has this extra lil bonus option file=filename, where filename is literally where your file output gets directed to. And if you don't say anything? It just defaults to fuse-sound.ao. Iconic default behaviour, honestly.

Some examples of use, because seeing it > reading it:

fuse -d alsa09:dev=hw:1

causes Fuse to use ALSA 0.9+ output with the second (#1) sound card.

fuse -d raw:byteorder=little,file=enigma.raw

causes Fuse to save little endian words to enigma.raw. 🎀

Also real talk, go peep the DEVICE section of ogg123(1) for up to date info on devices and options — except for the file option, which is provided by Fuse itself, so that one's ours, hands off. 🙈

---

🦋 If you're on libasound / ALSA 🦋

If you are using libasound or ALSA for sound output, the device parameter lets you specify the device used for sound output plus some parameters to be used for that device. In general, the device parameter has the form:

devstr or
param[=value][,param[=value][,...][,devstr].

• devstr — selects the ALSA device used, and it can be any complex or simple ALSA device name, fr fr. Like, e.g.: default or hw:0 or tee:plughw:0,'/tmp/out.raw',raw. Go see the alsa-lib pcm api reference at http://www.alsa-project.org/alsa-doc/alsa-lib/pcm.html for the further explanation, bestie, they got the deep lore.
• param and values:
  • buffer=nnnn — set the ALSA buffer in frames. Smaller value = smaller sound delay, but you might get more buffer underrun (that's pops and clicks, the WORST 😭). Larger value = longer delay but fewer underrun. By default Fuse determines the buffer size based on the actual sound frequency.

And okay, heads up on this one 👇 if you use some special plugin for your pcm device (e.g.: dmix) or your card doesn't support some needed parameter (e.g. cannot play other than only 48 kHz stereo sound like some AC97 sound card), it may cause Fuse to be unable to set the needed buffer size, appropriate sound frequency, channels and so on. Which means: you cannot get optimal result, or you hear nothing at all. Not a vibe. In this case try the plughw:#, (where # means your card number counted from 0) for ALSA device. 🫶

• verbose — if given, fuse reports ALSA buffer underruns to stderr.

Some examples of use:

fuse -d verbose,buffer=2000

causes Fuse to use the default ALSA device with 2000 frame length buffer and report ALSA buffer underruns on stderr.

fuse -d tee:plughw:0,'/tmp/aufwm.raw',raw

causes Fuse to use the first card and parallel save the raw audio samples into /tmp/aufwm.raw file. Slay. ✨

---

🌸 If you're on PulseAudio 🌸

If you are using PulseAudio for sound output, the device parameter lets you specify some parameters to be used for that soud buffer. In general, the device parameter has the form:

param[=value][,param[=value][,...].

• param and values:
  • tlength=[num]ms — set target length of the PulseAudio sound buffer in milliseconds. Smaller value = smaller sound delay but more buffer underruns (pops and clicks 😭), larger value = longer delay but fewer underruns. By default Fuse sets the buffer size to 30ms of sound delay.
  • tlength=num — set target length of the PulseAudio sound buffer in bytes. By default Fuse sets the buffer size to 30ms of sound delay. (Yes bestie, same default, different unit. We don't make the rules.)
  • verbose — if given, Fuse reports PulseAudio buffer underruns to stderr and PulseAudio buffer options to stdout. Two streams, one flag. 👑

Some examples of use:

fuse -d tlength=40ms

causes Fuse to target 40ms of sound delay instead of the default 30ms.

fuse -d verbose,tlength=2646

causes Fuse to request a sound buffer of 2646 bytes and print info to stdout.

---

• --sound-force-8bit — Force the use of 8-bit sound, even if 16-bit is possible. Same as the Sound Options dialog's Force 8-bit option. Downgrade era, but make it intentional. 💅
• -f frequency, --sound-freq frequency — Specify what frequency Fuse should use for the sound device. The default is 44.1 kHz, but some devices only support a single frequency or a limited range (e.g. 48 kHz or up to 22 kHz). Picky lil devices, we still love them. 🎀
• --speaker-type type — Select the output speaker emulation, where type can be TV speaker, Beeper or Unfiltered. Same as the Sound Options dialog's Speaker type option.
• --speccyboot — Emulate a SpeccyBoot Ethernet interface. Same as the General Peripherals Options dialog's SpeccyBoot option. See the SpeccyBoot web page at http://patrikpersson.github.io/speccyboot/ for full details on the SpeccyBoot. 🌈
• --speccyboot-tap device — Specify the TAP device to use for SpeccyBoot emulation.
• --specdrum — Emulate a SpecDrum interface. Same as the Sound Peripherals Options dialog's SpecDrum option. See the World of Spectrum Infoseek web page at http://www.worldofspectrum.org/infoseekid.cgi?id=1000062 for manuals, software and more. 🍓
• --spectranet — Specify whether Fuse will emulate the Spectranet Ethernet interface. Same as the General Peripherals Options dialog's Spectranet option. See the SPECTRANET EMULATION section for more details.
• --spectranet-disable — This option controls the state of the Spectranet automatic page-in jumper (J2). Same as the General Peripherals Options dialog's Spectranet disable option. See the SPECTRANET EMULATION section for more details.
• --speed percentage — Specify the speed (as a percentage of real Spectrum speed) at which emulation should attempt to proceed. Same as the General Options dialog's Emulation speed option. Go fast, go slow, go feral. 🔥
• --statusbar — For the GTK and Win32 UI, enables the statusbar beneath the display. For the Xlib and SDL UI, enables the status icons showing whether the disk and tape are being accessed. Same as the General Options dialog's Show statusbar option. Tiny bar, big information energy.
• -t file, --tape file — Specify a virtual tape file to use. It must be in PZX, TAP or TZX format. No other formats, bestie, don't try it.
• --teletext-addr-1 address, --teletext-addr-2 address, --teletext-addr-3 address, --teletext-addr-4 address — Specify address or hostname of teletext packet servers.
• --teletext-port-1 port, --teletext-port-2 port, --teletext-port-3 port, --teletext-port-4 port — Specify TCP port of teletext packet servers.
• --textfile file — Set the filename used for text output from the emulated printers. See the PRINTER EMULATION section below for more details. 🖨️
• --traps — Support traps for ROM tape loading/saving. (Enabled by default, but you can use --no-traps to disable.) Same as the Media Options dialog's Use tape traps option.
• --ttx2000s — Emulate a TTX2000S teletext adaptor. Same as the General Peripherals Options dialog's TTX2000S option. See the TTX2000S EMULATION section for more details. 💜
• --unittests — This option runs a testing framework that automatically checks portions of code, comparing actual results with expected ones. It is meant to detect broken code before a release. There is not graphical mode, the program just ends with exit code 0 if all tests are good, or prints error messages to stdout and ends with exit code greater than 0 if there are failed tests. Passing tests = the vibe check was passed. 🫶
• --usource — Emulate a µSource interface. Same as the General Peripherals Options dialog's µSource option.
• --uspeech — Emulate a µSpeech interface. Same as the Sound Peripherals Options dialog's µSpeech option.
• -V, --version — Show which version of Fuse is being used. You will be asking this at some point, we all do. 👑
• --volume-ay volume — Sets the relative volume of the AY-3-8912 chip from a range of 0–100%. Same as the Sound Options dialog's AY volume option.
• --volume-beeper volume — Sets the relative volume of the beeper from a range of 0–100%. Same as the Sound Options dialog's Beeper volume option.
• --volume-covox volume — Sets the relative volume of the Covox from a range of 0–100%. Same as the Sound Options dialog's Covox volume option.
• --volume-specdrum volume — Sets the relative volume of the SpecDrum from a range of 0–100%. Same as the Sound Options dialog's SpecDrum volume option.
• --volume-uspeech volume — Sets the relative volume of the µSpeech from a range of 0–100%. Same as the Sound Options dialog's uSpeech volume option.
• --writable-roms — Allow Spectrum programs to overwrite the ROM(s). The same as the General Options dialog's Allow writes to ROM option. Chaos mode, but make it emulator-endorsed. 💀
• --zxatasp — Specify whether Fuse emulate the ZXATASP interface. Same as the Disk Peripherals Options dialog's ZXATASP interface option.
• --zxatasp-upload — Specify the state of the ZXATASP upload jumper. Same as the Disk Peripherals Options dialog's ZXATASP upload option.
• --zxatasp-write-protect — Specify the state of the ZXATASP write protect jumper. Same as the Disk Peripherals Options dialog's ZXATASP write protect option.
• --zxatasp-masterfile file — Specify a HDF file to connect to the emulated ZXATASP interface's master channel.
• --zxatasp-slavefile file — Specify a HDF file to connect to the emulated ZXATASP interface's slave channel.
• --zxcf — Specify whether Fuse emulate the ZXCF interface. Same as the Disk Peripherals Options dialog's ZXCF interface option.
• --zxcf-upload — Specify the state of the ZXCF upload jumper. Same as the Disk Peripherals Options dialog's ZXCF upload option.

---

• --zxcf-cffile file — points Fuse at a HDF file to hook up to the emulated ZXCF interface. 💾
• --zxmmc — turns on the ZXMMC interface emulation. literally the same thing as the ZXMMC interface option in the Disk Peripherals Options dialog, no cap.
• --zxmmc-file file — says which HDF image gets loaded into the ZXMMC's emulated memory card. 🎀
• --zxprinter — emulate the ZX Printer. same as the ZX Printer option in the General Peripherals Options dialog. 🖨️

Okay so here's the cheat code for all the long options that control on/off settings, bestie: you can turn any of them off with --no-foo (where --foo is the option). so for example, the opposite of --issue2 is --no-issue2. iconic. ✨

These options can also be changed while the emulator is running, using the options dialogs — go read the docs for the Options menu in the MENUS AND KEYS section for the full tea. 👑

---

🌈 THE VARIOUS FRONT-ENDS 🌈

Fuse ships with a few different front-ends, aka UIs (user interfaces). the usual suspect is the GTK one, but there's also SDL, Win32, Xlib and framebuffer versions. 💅

The big difference you gotta know: the GTK and Win32 versions use native dialog boxes and stuff (so they act like a pretty normal GUI program), while all the others use a different thing called Fuse's own widget UI. You can clock that one instantly because it uses the main Fuse window/screen for its menus and dialogs, and it renders everything in the Spectrum's own font. 🦋

---

👑 MENUS AND KEYS 👑

So, because a ton of the keys are already doing labour emulating the Spectrum's keyboard, the main way you drive Fuse itself (as opposed to the emulated machine) is through the menus. Some menu options also get function key shortcuts, because convenience. 💖

On GTK and Win32, the menu bar lives permanently at the top of the Fuse window — click a menu name and it pops up. OR, press F1 to bring up a pop-up version of the menu bar, then steer it with the cursor keys or your mouse. 🖱️

On the widget UI, pressing F1 is the only way in to the main menu, and unlike the GTK version, the emulator pauses while you're navigating the menus. Each menu option shows which key to press next to it, in brackets. Esc backs you out of a menu, and Enter exits the whole menu system (and also confirms whatever dialog is currently up). ✨

Here's the rundown of what every menu option actually does, plus the function key mappings for the ones lucky enough to have them:

File, Open... — F3

Opens a Spectrum file. Snapshots get loaded into memory; tape images get slotted into the emulated tape deck, and if the Auto-load media option is set they'll start loading. Opening a disk image or a Timex dock image makes Fuse switch to the right machine type (+3, Pentagon or TC2068) with the image already inserted, and disks auto-load if Auto-load media is on. Need to know how to pick the file? See the FILE SELECTION section below. lowkey important: this behaviour is different from older versions of Fuse, where this option would only open snapshots. 🙈

File, Save Snapshot... — F2

Save a snapshot (machine state, memory contents, all of it) out to a file. You get to pick the filename. If it ends in .szx, .z80 or .sna, Fuse saves the snapshot in that format. otherwise? it's going out as a .szx file. periodt. 💾

File, Recording, Record...

Starts recording your input to an RZX file, initialised from whatever the emulation state is right now. You'll get asked for a filename to use. 🎥

File, Recording, Record from snapshot...

Starts recording input to an RZX file, but initialised from a snapshot instead. You'll be asked for the snapshot first, then the file to save the recording to.

File, Recording, Continue recording...

Keeps recording input into an existing RZX file, from the last recorded state. Heads up: finalised recordings cannot be resumed. You'll be prompted for the recording you want to continue. 😭

File, Recording, Insert snapshot — Insert

Drops a snapshot of the current state into the RZX file. Later on you can roll back to that inserted state using one of the commands below. 🫶

File, Recording, Rollback — Delete

Rolls the recording back to the point where the previous snapshot was inserted. Recording carries on from there.

File, Recording, Rollback to...

Rolls the recording back to any snapshot that's been inserted into the recording.

File, Recording, Play...

Plays back recorded input from an RZX file, so you can replay keypresses that were recorded earlier. RZX files usually have a snapshot inside with the Spectrum's state at the start of the recording; if the RZX file you picked doesn't, you'll be prompted for a snapshot to load too. 🎬

File, Recording, Stop

Stops whatever RZX file is currently recording or playing.

File, Recording, Finalise...

Compacts an RZX file. Any interspersed snapshot gets removed, and after this the recording cannot be continued. Every action replay you submit to the RZX Archive should be finalised. ⭐

File, AY Logging, Record...

Starts recording the bytes that get output through the AY-3-8912 sound chip into a PSG file. You'll be prompted for a filename to save the recording to. 🔊

File, AY Logging, Stop

Stops any AY logging that's currently happening.

File, Screenshot, Open SCR Screenshot...

Loads an SCR screenshot (which is basically just a binary dump of the Spectrum's video memory) onto the current screen. Fuse handles screenshots saved in Timex hi-colour and hi-res modes as well as normal Spectrum screens, and it'll do a simple conversion if you load a hi-colour or hi-res screenshot onto a non-Timex machine. 🌸

File, Screenshot, Save Screen as SCR...

Saves whatever's on the Spectrum's screen right now as an SCR file. You'll be prompted for a filename to save the screenshot to. 📸

File, Screenshot, Open MLT Screenshot...

Loads an MLT screenshot onto the current screen. MLT is similar to SCR but it also supports capturing images that use techniques to show more than two colours in each Spectrum attribute square. On a Sinclair machine Fuse will only load the bitmap version of an image, but on a Timex clone it can show the full colour detail captured in the image by using hi-colour mode. 🌈

File, Screenshot, Save Screen as MLT...

Saves whatever's on the Spectrum's screen right now as an MLT file. You'll be prompted for a filename to save the screenshot to.

File, Screenshot, Save Screen as PNG...

Saves the current screen as a PNG file. You'll be prompted for a filename to save the screenshot to. ✨

File, Scalable Vector Graphics, Start capture in line mode...

Starts trapping the video output functions that live in ROM so it can copy the picture out to SVG files, making a vectorized scalable picture. Realistically it's expected to be fully operational in BASIC only, though a few machine code programs could work if they use the ROM addresses to output text or graphics. The initial picture size is 256×176, and it grows everytime a scroll happens. Every time there's a CLS, a new file gets created with an increasing sequence number. CIRCLEs get described as a sequence of lines, so the original imprecisions will still be visible. Text output gets fully understood and decoded: normal ASCII characters turn into COURIER scalable fonts, UDG graphics into dot matrix areas, and GRAPHICS blocky characters into small squares. A slightly transparent output lets a bit of the overlapped text and graphics elements show through. The lower portion of the screen (normally bound to stream #0 and #1) won't be captured. 🎨

File, Scalable Vector Graphics, Start capture in dot mode...

Same as above, but line capture is disabled — a line gets rendered as a sequence of dots.

File, Scalable Vector Graphics, Stop capture

Stops the SVG capture function. 💅

File, Movie, Record...

Fuse can record a movie (video and audio) into a file with a special format, which can later be converted to a common video file format with the fmfconv(1) utility. You'll be prompted for a filename to save the video to. Please see the MOVIE RECORDING section. 🎥

File, Movie, Record from RZX...

Starts movie recording and RZX playback at the same time. You'll be prompted for a filename to play from and a filename to save the video to.

File, Movie, Pause

Pauses a movie recording that's currently in progress. ⏸️

File, Movie, Continue

Resumes a movie recording that was previously paused. ▶️

File, Movie, Stop

Stops a movie recording that's currently in progress.

File, Load Binary Data...

Loads binary data from a file into the Spectrum's memory. After you pick the file to load from, you can choose where the data gets loaded and how much of it to load. 💾

File, Save Binary Data...

Saves an arbitrary chunk of the Spectrum's memory to a file. Pick the file you want to save to, then the location and the length of the data you want saved.

File, Exit — F10

Exits the emulator. A confirmation dialog pops up first, checking that you actually want to do this. 👋

Options, General... — F4

Brings up the General Options dialog so you can configure Fuse. (On the widget UI, the keys shown in brackets toggle the options, Enter confirms any changes, and Esc aborts.) Quick note: any settings you change only apply to the currently-running Fuse. 🫶

The options available are:

Emulation speed

Sets how fast Fuse will attempt to emulate the Spectrum, as a percentage of the speed at which the real machine runs. If your machine can't keep up with the speed you asked for, Fuse will just run as fast as it can. Heads up: if the emulation speed is faster than 500%, no sound output will be produced. 💀

Frame rate

Specify the frame rate — the ratio of spectrum frame updates to real frame updates. This is useful if your machine is having trouble keeping up with the spectrum screen updates. 🌟

• Issue 2 keyboard — ok so back in the day, early Spectrum models used a different value for the unused bits on the keyboard input ports, and a few games were lowkey built around that old value. Turn this on and Fuse switches to the old value so you can actually run them. 🕹️
• Recreated ZX Spectrum — enables use of a Recreated ZX Spectrum in Layer A (game) mode. It's a Bluetooth keyboard, and you pair it to whatever device Fuse is running on. 🦋
• Use shift with arrow keys — decides how the keyboard arrow keys behave: either shifted, like the arrows on a ZX Spectrum+ keyboard, or unshifted, like a cursor joystick that maps to the 5, 6, 7 and 8 keys. Choose your fighter. 💅
• Allow writes to ROM — with this on, Fuse will happily let programs overwrite what would normally be ROM. Ngl it's probably not very useful in most situations, especially since the 48K ROM overwrites parts of itself anyway. 🙈
• Late timings — if selected, Fuse makes all the screen-related timings (like when the screen gets rendered and when memory contention happens) one tstate later than “normal” — an effect that genuinely shows up on some real hardware. ⏱️
• Z80 is CMOS — makes Fuse emulate a CMOS Z80 instead of an NMOS Z80. The undocumented OUT (C),0 instruction gets swapped for OUT (C),255, and emulation of a minor timing bug in the NMOS Z80's LD A,I and LD A,R instructions gets disabled. iconic behaviour tbh. 🔥
• RS-232 handshake — turn this off and Fuse just assumes the RS-232 line's other end is live when you connect the communication channels. See also the --rs232-rx and --rs232-tx options. 👑
• Black and white TV — lets you pick whether to simulate a colour or a black and white television. Heads up: this only does anything under the GTK, Win32, Xlib and SDL user interfaces — the others will always simulate a colour TV. 🌈
• Show statusbar — for the GTK and Win32 UI, this enables the statusbar underneath the display. For the SDL UI, it enables the status icons that show whether the disk and tape are being accessed. For every other user interface, this option does nothing at all. 💀
• Snap joystick prompt — if set, Fuse will ask you which physical joystick or keyboard you want to connect to the joystick interface that got enabled in the snapshot, unless it already matches your current configuration. 🎮
• Confirm actions — sets whether dangerous actions (the kind that could cause data loss, like resetting the Spectrum, bestie) need confirmation before they happen. 🚨
• Auto-save settings — if this is selected, Fuse automatically writes its currently selected options to its configuration file on exit (either xml format if libxml2 was available when Fuse was compiled, or plain text). If it's off, you'll have to manually use Options, Save afterwards to make sure the setting gets written to Fuse's config file. 👀 Note that if you turn this on, loading a snapshot could enable peripherals that then get written permanently to the configuration file.

---

✨ Options, Media... ✨

This one pops open the Media Options dialog so you can configure Fuse's tape and Microdrive options. (With the widget UI, the keys shown in brackets toggle the options, Enter confirms any changes, and Esc aborts.) Just so you know — any changed settings only apply to the currently-running Fuse. 🎀

• Auto-load media — so when you open a tape or disk file, it's usually because there's a program on it you wanna load and run, right? If this option is selected, that just happens automatically when you open one of those files using the File, Open... menu option. But bestie, then you have to use the Media menu to use tapes or disks for saving data to, or for loading data into an already-running program. 📼
• Detect loaders — with this enabled, Fuse tries to detect when a loading routine is in progress and then automatically starts the virtual tape to load the program in. It does this with a heuristic to spot a loading routine, so it's by no means infallible, but it works in most cases. 🔍
• Phantom typist mode — sets the keystroke sequence the "phantom typist" should use when starting a program loading. The options are:
  • Auto
  • Keyword
  • Keystroke
  • Menu
  • Plus 2A
  • Plus 3

The first four correspond to automatic detection based on machine model, keyword-based entry, keystroke-based entry, and selection from a 128K style menu. Plus 2A and Plus 3 also mean selection from a 128K style menu, but they have special handling for games that need to be loaded with LOAD ""CODE. The most likely use for this option is use Keystroke if you've changed the default 48K ROM for one with keystroke entry. ⌨️

• Fastloading — if enabled, Fuse runs at the fastest possible speed while the virtual tape is playing, so the time it takes to load programs drops dramatically. You might wanna disable this if you want to stop the tape at a specific point. ⚡
• Use tape traps — normally Fuse intercepts calls to the ROM tape-loading routine so it can load from tape files more quickly when possible. But this can (rarely) interfere with TZX loading; disabling this option avoids that problem at the cost of slower (i.e. always real-time) tape-loading. When tape-loading traps are disabled, you need to start tape playback manually, by pressing F8 or choosing the Media, Tape, Play menu item. Fuse also uses tape traps to intercept the tape-saving routine in the ROM to save tape files quickly — tapes can also be saved using the Media, Tape, Record Start menu item. 🧚
• Accelerate loaders — if enabled, Fuse will try to accelerate tape loaders by “short circuiting” the loading loop. This speeds up loading in general, but it may cause some loaders to fail. 😭
• Use .slt traps — the multi-load aspect of SLT files needs a trap instruction to be supported. This instruction isn't generally used except for this trap, but since it's not inconceivable that a program might want to use the real instruction instead, you get to choose whether to support the trap or not. 🍓
• MDR cartridge len — this controls the number of blocks in a new Microdrive cartridge. If the value is smaller than 10 or greater than 254, Fuse assumes 10 or 254. Average real capacity is around 180 blocks (90 Kb). 💾
• Random length MDR cartridge — if enabled, Fuse uses a random Microdrive cartridge length (around 180 blocks) instead of the length specified in the MDR cartridge len option. 🎲

---

💜 Options, Sound... 💜

This opens the Sound Options dialog so you can configure Fuse's sound output. (With the widget UI, the keys shown in brackets toggle the options, Enter confirms any changes, and Esc aborts.) Fr fr, any changed settings only apply to the currently-running Fuse. 🔊

• Sound enabled — says whether sound output should be enabled at all. When this is disabled, Fuse makes no sound whatsoever. 🤫
• Loading sound — normally Fuse emulates tape-loading noise when loading from PZXs, TAPs or TZXs in real-time, though at a deliberately lower volume than on a real Spectrum. Disable this option to eliminate the loading noise entirely. 📻
• AY stereo separation — by default the sound output is mono, since that's all you got from an unmodified Spectrum. But enabling this gives you so-called ACB stereo (for sound from the 128 and other clones' AY-3-8912 sound chip). 🌸
• Force 8-bit — forces the use of 8-bit sound even if 16-bit (the default) is available. Careful though: when this option is enabled, if 8-bit sound isn't available then there will be no sound at all, so it's best not to use this unless you have a specific need for it. 💀
• Speaker type — lets you modify the emulation of the sound output system. Different choices of speaker limit the bass and treble response that can come out of the machine. Choose between a “TV” type speaker and a small “Beeper” type speaker that significantly limits bass and treble response. Choose “Unfiltered” to get unmodified (but less accurate) sound output. 📺
• AY volume — sets the relative volume of the AY-3-8912 chip, across a range of 0–100%. 🎚️
• Beeper volume — sets the relative volume of the beeper, across a range of 0–100%. 🎚️
• Covox volume — sets the relative volume of the Covox, across a range of 0–100%. 🎚️
• SpecDrum volume — sets the relative volume of the SpecDrum, across a range of 0–100%. 🎚️
• µSpeech volume — slides the µSpeech's relative volume up and down across a range of 0–100%. Cute little dial, go wild 🎚️

---

✨ Options, Peripherals, General... ✨

This one pops open the General Peripherals Options dialog, where you get to tell Fuse which peripherals it should act like are physically plugged into the emulated machine. Bestie, this is dress-up but for hardware 💅 (When you're on the widget UI, the keys shown in brackets toggle the options, Enter confirms any changes, and Esc aborts.) Heads up: any changed settings only apply to the currently-running Fuse. And also — any changes that enable and disable peripherals may result in a hard reset of the emulated machine. Yeah. She's dramatic like that 😭

Kempston joystick

Pick this and Fuse will emulate a Kempston joystick interface — probably the most widely supported type on the Spectrum, iconic behaviour honestly. Ngl, this option is basically equivalent to plugging the interface itself into a Spectrum, not to connecting a joystick; this affects how the Spectrum responds to a read of input port 31. So to actually use a Kempston joystick in a game, this option must be enabled, and you must also select a Kempston joystick in the Options, Joysticks menu. Two steps, no shortcuts 🕹️

Kempston mouse

Select this and Fuse will emulate a Kempston mouse interface. 🐭

With the SDL and SDL2 UIs, middle click (or middle button release) on the Spectrum display toggles mouse grab when the Kempston mouse is enabled. When grabbed, SDL2 uses relative mouse mode so motion is no longer limited by the host pointer reaching the edge of the screen. Slay, no more bonking into the wall ✨

If you're using Fuse full-screen, your mouse is automatically used as if attached to the Kempston interface. Otherwise, you'll need to click on the Spectrum display in order to tell Fuse to grab the pointer (and make it invisible); to tell Fuse to release it, click the middle button (or wheel) or press Escape.

With the framebuffer UI, Fuse prefers to use GPM; if this is not available, it will fall back to built-in PS/2 mouse support. In this mode, it tries /dev/input/mice, /dev/mouse then /dev/psaux, stopping when it successfully opens one. The first of these is preferred since (at least on Linux, with a 2.6-series kernel) any type of mouse can be used and any connected mouse may be used. Sequential queen behaviour, we love to see it 👑

Swap mouse buttons

Enable this and the left and right mouse buttons will be swapped when emulating a Kempston mouse. Chaos mode for lefties and gremlins 🫶

Interface 1

Select this and Fuse will emulate the simple Sinclair Interface 1, and allow Microdrive cartridges to be connected and disconnected via the Media, Interface 1, Microdrive menus. It also enables support for the Interface 1 RS-232 interface. Very much giving vintage networking, iykyk 📼

Interface 2

Select this and Fuse will emulate a cartridge port as found on the Interface 2. Cartridges can then be inserted and removed via the Media, Cartridge, Interface 2 menu. Okay but important — the Pentagon, Scorpion, Interface 2, ZXATASP and ZXCF all use the same hardware mechanism for accessing some of their extended features, so only one of these should be selected at once or unpredictable behaviour will occur. One at a time, bestie, we are not doing that 💀

Multiface One

Select this and Fuse will emulate the Romantic Robot Multiface One. Available for 16K, 48K and Timex TC2048 machines.

Multiface 128

Select this and Fuse will emulate the Romantic Robot Multiface 128. Available for 16K, 48K, Timex TC2048, 128K, +2 and SE machines.

Multiface 3

Select this and Fuse will emulate the Romantic Robot Multiface 3. Available for +2A, +3 and +3e machines.

Stealth Multiface One

This option controls the invisible or stealth mode of Multiface One — literally the physical switch on the side of the interface, reimagined as a menu item. Sneaky ✨

Emulate printers

Select this and Fuse will emulate a printer. See the PRINTER EMULATION section for more details. 🖨️

ZX Printer

Select this and Fuse will emulate the ZX Printer. See the PRINTER EMULATION section for more details.

SpeccyBoot interface

Select this and Fuse will emulate a SpeccyBoot interface which allows booting a ZX Spectrum over an Ethernet network. See the SpeccyBoot web page at http://patrikpersson.github.io/speccyboot/ for more details. Boot over the network?? main character energy fr fr 🌐

Spectranet

Select this and Fuse will emulate the Spectranet interface, which provides an Ethernet interface for the Spectrum. See the SPECTRANET EMULATION section for more details.

Spectranet disable

This option controls the state of the Spectranet automatic page-in jumper (J2). See the SPECTRANET EMULATION section for more details.

TTX2000S

Select this and Fuse will emulate the OEL/Volex TTX2000S teletext adaptor. Available for the 16K and 48K machines. See the TTX2000S EMULATION section for more details. Teletext era, she ate 📺

µSource

Select this and Fuse will emulate a Currah µSource interface. See the World of Spectrum Infoseek web page at http://www.worldofspectrum.org/infoseekid.cgi?id=1000080 for the manual.

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🎀 Options, Peripherals, Sound... 🎀

This opens the Sound Peripherals Options dialog — here you configure the sound interface peripherals which Fuse will consider to be attached to the emulated machine. (With the widget UI, the keys shown in brackets toggle the options, Enter confirms any changes, and Esc aborts.) Same little disclaimer as before: any changed settings only apply to the currently-running Fuse. And also — any changes that enable and disable peripherals may result in a hard reset of the emulated machine. Same drama, new menu 😭

Covox interface

Select this and Fuse will emulate a Covox digital sound interface. This emulation is only available for the Pentagon, Pentagon 512k, Pentagon 1024k and Scorpion machines. The Pentagon variants use port 0xfb and the Scorpion version uses port 0xdd. Port numbers, no cap 🎧

Fuller Box

Select this and Fuse will emulate a Fuller Box AY sound and joystick interface. This emulation is only available for the 16k, 48k and TC2048 machines.

Melodik

Select this and Fuse will emulate a Melodik AY sound interface. These interfaces and many similar ones were produced to make the 48K Spectrum compatible with the same AY music as the 128K Spectrum. Historical glow-up, honestly. This emulation is only available for the 16k, 48k and TC2048 machines 🎶

SpecDrum interface

Select this and Fuse will emulate a Cheetah SpecDrum sound interface. See the World of Spectrum Infoseek web page at http://www.worldofspectrum.org/infoseekid.cgi?id=1000062 for manuals, software and more. This emulation is only available for the 48k, 128k and TC2048 machines 🥁

µSpeech

Select this and Fuse will emulate a Currah µSpeech interface. See the World of Spectrum Infoseek web page at http://www.worldofspectrum.org/infoseekid.cgi?id=1000081 for the manual, software and more. She speaks 💬

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🌸 Options, Peripherals, Disk... 🌸

And this one brings up the Disk Peripherals Options dialog, letting you configure the disk interface peripherals which Fuse will consider to be attached to the emulated machine. (With the widget UI, the keys shown in brackets toggle the options, Enter confirms any changes, and Esc aborts.) You already know the drill: any changed settings only apply to the currently-running Fuse, and any changes that enable and disable peripherals may result in a hard reset of the emulated machine. Same energy every time 💾

Simple 8-bit IDE

Select this and Fuse will emulate the simple 8-bit IDE interface as used by the Spectrum +3e, and allow hard disks to be connected and disconnected via the Media, IDE, Simple 8-bit menu.

ZXATASP interface

Select this and Fuse will emulate the ZXATASP interface, which provides both additional RAM and an IDE interface. See the ZXATASP AND ZXCF section for more details. RAM and IDE, she's an overachiever 💅

ZXATASP upload

This option controls the state of the ZXATASP upload jumper. See the ZXATASP AND ZXCF section for more details.

ZXATASP write protect

This option controls the state of the ZXATASP write protect jumper. See the ZXATASP AND ZXCF section for more details.

ZXCF interface

Select this and Fuse will emulate the ZXCF interface, which provides both additional RAM and a CompactFlash interface. See the ZXATASP AND ZXCF section for more details.

ZXCF upload

This option controls the state of the ZXCF upload jumper. See the ZXATASP AND ZXCF section for more details.

ZXMMC interface

Select this and Fuse will emulate the ZXMMC interface. Available for +2A, +3 and +3e machines.

DivIDE interface

Select this and Fuse will emulate the DivIDE interface. See the DIVIDE section for more details. 🦋

• DivIDE write protect — this one controls the state of the DivIDE write protection jumper. Wanna know more? The DIVIDE section has you covered 💅
• DivMMC interface — tick this and Fuse will emulate the DivMMC interface. Again, the DIVMMC section is where the lore lives.
• DivMMC write protect — controls the state of the DivMMC write protection jumper, aka the thing that stops you flashing the EEPROM chip 🫶 See the DIVMMC section for the full rundown.
• +D interface — select it and Fuse emulates the +D interface. Details in the +D EMULATION section.
• Didaktik 80 interface — select it and Fuse emulates the Didaktik 80 (or Didaktik 40) interface. See the DIDAKTIK 80 EMULATION section for more.
• DISCiPLE interface — select it and Fuse emulates the DISCiPLE interface. See the DISCIPLE EMULATION section.
• Beta 128 interface — select it and Fuse emulates the Beta 128 interface. See the BETA 128 EMULATION section. Heads up though: Beta 128 emulation is enabled for the Pentagon and Scorpion machines regardless of this option, so this toggle isn't the boss of them 💀
• Beta 128 auto-boot in 48K machines — tick this and, when a Beta 128 interface is being used in 48K or TC2048 emulation, the machine boots directly into the TR-DOS system. Straight in, no detours ✨
• Opus Discovery interface — select it and Fuse emulates the Opus Discovery interface. See the OPUS DISCOVERY EMULATION section for the tea.

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Options, RZX...

Opens the RZX Options dialog, where you get to decide how Fuse handles RZX input recordings. (With the widget UI, the keys written in brackets toggle the options, Enter confirms any changes you made, and Esc aborts the whole thing.) Just so you know: any settings you change only apply to the currently-running Fuse 💅

• Create autosaves — tick this and Fuse drops a snapshot into the recording stream every 5 seconds while it's making an RZX file. That means you get to use the rollback facilities without having to manually shove snapshots into the stream yourself. Older snapshots get pruned from the stream to keep the file size and the number of snapshots down: each snapshot up to 15 seconds is kept, then one snapshot every 15 seconds until one minute, then one snapshot every minute until 5 minutes, and after that, one snapshot every 5 minutes 🫶 Important: this "pruning" only applies to the automatically inserted snapshots — snapshots you insert manually into the stream will never be pruned, periodt.
• Compress RZX data — if this is selected, and zlib was available when Fuse was compiled, then any RZX files Fuse writes will be compressed. This is generally a good thing because it makes the files significantly smaller, and you probably only want to turn it off if you're debugging RZX files or if there's some other program out there that doesn't support compressed RZX files 😭
• Competition mode — any input recordings started while this is selected get made in 'competition mode'. Basically that means Fuse acts exactly like a real Spectrum would: you can't load snapshots, you can't pause the emulation in any way, you can't change the speed, you can't do anything you couldn't do on the actual real machine. And if you try any of that, or if the emulated Fuse is running more than 5% faster or slower than normal Spectrum speed, the recording is stopped immediately 💀

If libgcrypt was available when Fuse was compiled, then recordings made with competition mode active will be digitally signed — the idea being to 'certify' that the recording was made with all those restrictions in place. BUT: this procedure is not secure (and cannot be made secure), so the presence of any signature on an RZX file should not be taken as proof that it was made with competition mode active. This feature is in Fuse solely because it was one of the requirements for Fuse to be used in an on-line tournament. No cap ✋

• Competition code — whatever numeric code you type in here gets written into any RZX files made in competition mode. It's another on-line-tournament feature, and it can be used to 'prove' that the recording was made after a specific code was released. If you're not playing in one of those tournaments, you can safely ignore this option entirely 🎀
• Always embed snapshot — specify whether a snapshot should be embedded in an RZX file when recording is started from an existing snapshot.

Options, Movie...

Opens the Movie Options dialog, so you can configure how Fuse deals with movie recordings.

• Movie compression — sets the compression level to None, Lossless or High. (See the MOVIE RECORDING section for more info.) ✨
• Stop recording after RZX ends — tick this and Fuse will stop any movie recording once an RZX playback has finished.

Options, Joysticks

Fuse can emulate so many of the common joystick types that were out there for the Spectrum, and it's lowkey iconic. The input for these emulated joysticks can come from real joysticks plugged into the emulating machine (set up through the Options, Joysticks, Joystick 1... and Options, Joysticks, Joystick 2... options), or from the q, a, o, p, and Space keys on the emulating machine's keyboard, configured via the Options, Joysticks, Keyboard... option. Ngl there's a catch: when you're using the keyboard to emulate a joystick, the q, a, o, p, and Space keys will not have their normal effect — this avoids problems with games that do things like use p for pause while you're on a joystick 🙈

Each of the joysticks (including the 'fake' keyboard joystick) can be configured to emulate any one of these joystick types:

• None — no joystick at all: any input just gets ignored.
• Cursor — a cursor joystick, equivalent to pressing 5 (left), 6 (down), 7 (up), 8 (right), and 0 (fire).
• Kempston — a Kempston joystick, read from input port 31. Note that the Options, Peripherals, General, Kempston interface option also has to be set for the input to be recognised 👑
• Sinclair 1
• Sinclair 2 — the 'left' and 'right' Sinclair joysticks, equivalent to pressing 1 (left), 2 (right), 3 (down), 4 (up), and 5 (fire), or 6 (left), 7 (right), 8 (down), 9 (up), and 0 (fire) respectively.
• Timex 1
• Timex 2 — the 'left' and 'right' joysticks as attached to the Timex 2068 variant's built-in joystick interface.

For the real joysticks, you can also configure what effect each button on the joystick will have. It can be Joystick Fire, equivalent to pressing the emulated joystick's fire button; Nothing, meaning it has no effect; or any Spectrum key, meaning that pressing that button is equivalent to pressing that Spectrum key 💖

Options, Select ROMs, Machine ROMs

There's an individual dialog for each Spectrum variant Fuse emulates, and it lets you pick the ROM(s) that machine uses. Simple as: select the ROM you want, then reset the Spectrum for the change to take effect 💅

Options, Select ROMs, Peripheral ROMs

Same deal as the Machine ROMs menu, except there's an individual dialog for peripherals that need a ROM. Select the ROM you want to use, then reset the Spectrum for the change to take effect ✨

Options, Filter...

Pick the graphics filter currently in use. See the GRAPHICS FILTERS section for more details.

F11, Options, Full Screen

Flips Fuse between full screen and windowed mode. Heads up: this menu is only available under the GTK and SDL UIs 🫶

Options, Disk Options...

When it's emulating disk drives, Fuse lets you specify the physical drive units attached to the emulated interface. Each drive can be set to one of these types:

• Disabled
• Single-sided 40 track
• Double-sided 40 track
• Single-sided 80 track
• Double-sided 80 track

Watch out: the Disabled option is not supported for Drive 1 or Drive A of any interface 💀

The available options that can be set are:

• +3 Drive A — defaults to a single-sided 40 track drive.
• +3 Drive B — defaults to a double-sided 80 track drive.
• +3 Detect Speedlock — specify whether the +3 drives try to detect Speedlock protected disks and emulate 'weak' sectors. If the disk image file (EDSK or UDI) contains weak sector data, then Speedlock detection is automatically omitted. See also the WEAK DISK DATA section 🌸
• Beta 128 Drive A — defaults to a double-sided 80 track drive.
• Beta 128 Drive B — defaults to a double-sided 80 track drive.
• Beta 128 Drive C — defaults to a double-sided 80 track drive.
• Beta 128 Drive D — defaults to a double-sided 80 track drive.
• +D Drive 1 — defaults to a double-sided 80 track drive.
• +D Drive 2 — defaults to a double-sided 80 track drive.
• Didaktik 80 Drive A — defaults to a double-sided 80 track drive. 💾
• Didaktik 80 Drive B — also defaults to a double-sided 80 track drive. twin behavior, twin legend ✨
• DISCiPLE Drive 1 — defaults to a double-sided 80 track drive.
• DISCiPLE Drive 2 — yep, defaults to a double-sided 80 track drive too.
• Opus Drive 1 — defaults to a single-sided 40 track drive. different vibe, still valid 🎀
• Opus Drive 2 — defaults to a single-sided 40 track drive as well.

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• Try merge 'B' side of disks — bestie this one just asks you first: it prompts the user to confirm whether Fuse should try to merge the `B' side of a disk image from a separate file when opening a new single-sided disk image. consent-based merging, we love to see it 🫶
• Confirm merge disk sides — this is where you decide whether Fuse should try to merge a separate file for the B' side of a disk image separate file when opening a new disk image. (<purple>yes, really, that's what it says</purple> 💀). Okay so here's the *lore*: most double sided disk images are dumped as two single sided disk images, e.g. <pink>Golden Axe - Side A.dsk' and Golden Axe - Side B.dsk'</pink>. So if we want to play Golden Axe, first we have to insert the first disk image, and when the game asks to insert side B, we have to find and open the second disk image, instead of just flip-ing the disk inside the drive. <yellow>ngl that's giving chores</yellow> 😭. But if enabled, Fuse will try to open the second image too and create a double sided disk image (merging the two one sided disk images) and insert this merged virtual disk into the disk drive. The function detects whether the file is one side of a double-sided image if the filename matches a pattern like <hotpink>[Ss]ide[ _][abAB12][ _.]</hotpink> in the file name of a disk that is being opened. If found, Fuse will try to open the other side of the disk too, substituting the appropriate characters in the filename e.g. <cyan>1→2</cyan>, <cyan>a→b</cyan>, <cyan>A→B</cyan>. If successful then it will merge the two images and now we have a double sided disk in drive. 💅 This means that if we open <pink>Golden Axe - Side A.dsk', then Fuse will try to open Golden Axe - Side B.dsk'</pink> too. Now, we can just flipthe disk if Golden Axe asks forSide B'. so iconic. The available options are Never, With single-sided drives and Always.

🎀 Options, Save

This will cause Fuse's current options to be written to a configuration file in your home directory, from which they will be picked up again when Fuse is restarted. ✨ The best way to update this file is by using this option, but it's a simple XML file if libxml2 was available when Fuse was compiled (otherwise, plain text), and shouldn't be too hard to edit by hand if you really want to. See the FILES section for more details about location of this file. 📁

⏸️ Pause

Machine, Pause

Pause or unpause emulation. This option is available only under the GTK and Win32 UIs; to pause the other user interfaces, simply press F1 to bring up the main menu. iykyk

🔄 F5

Machine, Reset

Reset the emulated Spectrum. fresh start energy ✨

Machine, Hard reset

Reset the emulated Spectrum. A hard reset is equivalent to turning the Spectrum's power off, and then turning it back on. 🔌 like ripping the plug out and plugging it back in, no cap

👑 F9

Machine, Select...

Choose a type of Spectrum to emulate. A brief overview of the Sinclair, Amstrad and Timex can be found at http://www.nvg.ntnu.no/sinclair/computers/zxspectrum/zxspectrum.htm while more technical information can be found at http://www.worldofspectrum.org/faq/reference/reference.htm, and http://www.worldofspectrum.org/faq/reference/tmxreference.htm. 🦋

• Spectrum 16K / Spectrum 48K — the original machines as released by Sinclair in 1982 with 16 or 48K of RAM respectively. the OGs, the moment, the blueprint 💖
• Spectrum 48K (NTSC) — the NTSC 48K machine released in limited numbers in parts of South America. 🌎 rare queen behavior
• Spectrum 128K — the 128K machine as released by Sinclair in 1985 (Spain) or 1986 (UK).
• Spectrum +2 — the first machine released by Amstrad, in 1986. From an emulation point of view, the +2 is virtually identical to the 128K. basically the same girl different era 💅
• Spectrum +2A / Spectrum +3 — the two machines released by Amstrad in 1988. Technically very similar to each other, except that the +3 features a 3″ disk drive while the +2A does not. 💾
• Spectrum +3e — a +3 with modified ROMs allowing access to IDE hard disks via the simple 8-bit interface, as activated from the Options, Peripherals, Disk... dialog. See http://www.worldofspectrum.org/zxplus3e/ for more details. the glow-up era ⭐
• Timex TC2048 / Timex TC2068 — the variants of the Spectrum as released by Timex in Portugal. 🇵🇹
• Timex TS2068 — the variant of the Spectrum released by Timex in North America. 🇺🇸
• Pentagon 128K — Russian clone of the Spectrum. There were many different machines called Pentagon from 1989 to 2006; this machine corresponds to a 1991 era Pentagon 128K with the optional AY sound chip and the integrated Beta 128 disk interface, and is the version of the machine most often emulated. More technical details can be found at http://www.worldofspectrum.org/rusfaq/index.html, <flutter>main character of the clone universe fr fr</flutter> 🔥
• Pentagon 512K / Pentagon 1024K — newer versions of the Pentagon Russian Spectrum clones which incorporate more memory and the “Mr Gluk Reset Service” ROM offering a more powerful firmware. more RAM, more ROM, more everything 💜
• Scorpion ZS 256 — another Russian clone of the Spectrum. Some details can be found at http://www.worldofspectrum.org/rusfaq/index.html. Like all the Russian clones, they have built in 3.5″ disk drives, accessed via the Beta 128 disk interface and TR-DOS (the Technology Research Disk Operating System). The most important distinction from the Pentagon 128k and similar machines is the display timing details. timing drama, that's the whole tea 😭
• Spectrum SE — a recent variant designed by Andrew Owen and Jarek Adamski, which is possibly best thought of as a cross between the 128K machine and the Timex variants, allowing 272K of RAM to be accessed. Some more details are available at http://www.worldofspectrum.org/faq/reference/sereference.htm and documentation of the extended BASIC is available at https://github.com/cheveron/sebasic4/wiki. The bug tracker for the BASIC is at https://github.com/cheveron/sebasic4/issues?state=open. 🐛

Machine, Debugger...

Start the monitor/debugger. See the MONITOR/DEBUGGER section for more information. 🔍

Machine, Poke Finder...

Start the `poke finder'. See the POKE FINDER section for more information. 🕵️♀️

Machine, Poke Memory...

Allow one to use multiface POKEs for things such as infinite lives. See the POKE MEMORY section for more information. your fave: infinite lives, the blueprint ♾️

Machine, Memory Browser...

Start the memory browser. It should be fairly obvious what this does; perhaps the only thing worth noting is that emulation is paused until you close the window. ⏸️

Machine, Profiler

Start or stop the built-in Z80 execution profiler. When profiling is started, Fuse records the cumulative number of t-states spent at each program counter address. When profiling is stopped, Fuse prompts for a filename and writes the collected data as text, one non-zero address per line, in the form 0x1234,456 where the first value is the address and the second is the cumulative t-state count. 📊

This output can be converted with profile2map(1) from the fuse-utils package into the opcode map-file format used by Gerton Lunter's Z80 Spectrum emulator. Such map files can be used by external tools such as dZ80 (http://inkland.org.uk/dz80/) to help distinguish executed code from unexecuted data. data science but make it 1982 ✨

Machine, NMI

Sends a non-maskable interrupt to the emulated Spectrum. Due to a typo in the standard 48K ROM, this will cause a reset, but modified ROMs are available which make use of this feature. heads up: typo in the ROM = surprise reset, that is very much a real thing 💀 When the +D (or DISCiPLE) is emulated, this is used to access the +D (or DISCiPLE)'s screenshot and snapshot features (see the +D EMULATION and DISCIPLE EMULATION sections below). For the DISCiPLE, Caps Shift must be held down whilst pressing the NMI button. For some UIs, this may be tricky, or even impossible to do. Note that GDOS on the DISCiPLE contains a bug which causes corruption of saved snapshots, and a failure to return from the NMI menu correctly. This bug is not present in G+DOS on the +D. so iconic that even the bugs are documented 😭

Machine, Multiface Red Button

Presses the Multiface One/128/3 red button to active the interface. 🔴 press the shiny button, that's it, that's the whole job

Machine, Didaktik SNAP

Presses the Didaktik 80 (or Didaktik 40)'s `SNAP' button. 📸

📼 F7

Media, Tape, Open...

Choose a PZX, TAP or TZX virtual-tape file to load from. See the FILE SELECTION section below for details on how to choose the file. If Auto-load media is set in the Media Options dialog (as it is by default), you may use the File, Open... menu option instead, and the tape will begin loading automatically. Otherwise, you have to start the load in the emulated machine (with LOAD "" or the 128's Tape Loader option, though you may need to reset first). 🦋

To guarantee that TZX files will load properly, you should select the file, make sure tape-loading traps are disabled in the Media Options dialog, then press F8 (or do Media, Tape, Play). That said, most TZXs will work with tape-loading traps enabled (often quickly loading partway, then loading the rest real-time), so you might want to try it that way first. ✨ tl;dr: try the easy way, then hit it with the F8 technique if it's being dramatic

• F8 / Media, Tape, Play — bestie, this hits play on the PZX, TAP or TZX file if that's what's needed. Choosing the option again (or pressing F8 again, same energy) pauses playback, and one more press resumes it. Okay let me explain the lore: if tape-loading traps have been disabled (that's in the Media Options dialog, iykyk), then just kicking off the loading process inside the emulated machine is not enough. You literally have to press play, so to speak :-), and this is the whole entire way you do that. You might also need to press play like this in certain other circumstances too — say a TZX with a multi-load game politely sending a stop-the-tape request, which Fuse obeys. 💅
• Media, Tape, Browse — scroll through the current tape, tour style ✨. A brief display of each of the data blocks on the current tape pops up, and from there you pick which block Fuse will play next. With the GTK UI, emulation keeps going while the browser is on screen, and double-clicking a block selects it. In the other UIs, emulation is paused and you use the cursor keys plus Enter to select. Changed your mind and don't wanna switch blocks? Just press Escape. 🦋
• Media, Tape, Rewind — rewind the current virtual tape so it can be read all over again from the beginning. Rewind culture. 📼
• Media, Tape, Clear — wipes the current virtual tape clean. Lowkey the MVP when you want a clean slate to add newly-saved files onto before going Media, Tape, Write... (or F6). 🧼
• F6 / Media, Tape, Write... — writes the current virtual-tape contents out to a TZX file. You'll be prompted for a filename, obviously. And here's what "virtual-tape contents" means: the contents of the previously-loaded tape (if any has been loaded since you last did a Media, Tape, Clear), followed by anything you've saved from the emulated machine since then. 🫶 These newly-saved files are not written to any tape file until you choose this option! Periodt.
• Media, Tape, Record Start — starts recording the output from the emulated Spectrum directly to the current virtual-tape. Iconic if you want to record using a non-standard ROM or from a custom save routine. Heads up: most tape operations are disabled during recording. 🚫 Stop the recording with the Media, Tape, Write... menu option.
• Media, Tape, Record Stop — stops the direct recording and drops the new recording into the virtual-tape. That's it, that's the job. 💖
• Media, Interface 1 — virtual Microdrive images are only accessible when the Interface 1 is active, from the Options, Peripherals, General... dialog. And listen: any changes to the Microdrive image will not be written to the file on disk until you use the appropriate save option. No cap. 😭
• Media, Interface 1, Microdrive 1, Insert New — inserts a brand-new (unformatted) Microdrive cartridge into emulated Microdrive 1. Fresh out the box energy. ✨
• Media, Interface 1, Microdrive 1, Insert... — inserts an existing Microdrive cartridge image into emulated Microdrive 1. You will be prompted for a filename. 📁
• Media, Interface 1, Microdrive 1, Eject — ejects the Microdrive image in Microdrive 1. If the image has been modified, you'll be asked whether you want any changes saved. It's giving considerate. 💅
• Media, Interface 1, Microdrive 1, Save — saves the Microdrive image in Microdrive 1. 🎀
• Media, Interface 1, Microdrive 1, Save as... — writes the Microdrive image in Microdrive 1 to a file. You will be prompted for a filename.
• Media, Interface 1, Microdrive 1, Write protect, Enable — enables the write protect tab for the image in Microdrive 1. 🔒
• Media, Interface 1, Microdrive 1, Write protect, Disable — disables the write protect tab for the image in Microdrive 1. 🔓
• Media, Interface 1, Microdrive 2, ..., Media, Interface 1, Microdrive 3, ..., Media, Interface 1, Microdrive 4, ..., Media, Interface 1, Microdrive 5, ..., Media, Interface 1, Microdrive 6, ..., Media, Interface 1, Microdrive 7, ..., Media, Interface 1, Microdrive 8, ... — equivalent options for the other emulated Microdrives. Same vibe, different drive number. 💜
• Media, Interface 1, RS232, Plug RxD, Media, Interface 1, RS232, Unplug RxD, Media, Interface 1, RS232, Plug TxD, Media, Interface 1, RS232, Unplug TxD — connect or disconnect a communication channel (a FIFO or a file) to use as the RS-232 TxD or RxD wire. Plug it in, unplug it, your call bestie. 🌈
• Media, Disk — virtual floppy disk images are accessible when you're emulating a +3, +3e, Pentagon or Scorpion, or when the Beta 128, Opus Discovery, +D, Didaktik or DISCiPLE interface options are enabled and a machine compatible with the chosen interface is selected. (For the deets on which file formats are supported, check the THE .DSK FORMAT, BETA 128 EMULATION, OPUS DISCOVERY EMULATION, +D EMULATION, DIDAKTIK 80 EMULATION and DISCIPLE EMULATION sections below. 👀)

And once again: any changes made to a disk image will not affect the file which was inserted into the drive. Slightly rude of it, honestly. If you do want to keep any changes, use the appropriate eject and write option before exiting Fuse. Don't say I didn't warn you. 💀

• Media, Disk, +3, Drive A:, Insert... — inserts a disk-image file to read/write in the +3's emulated drive A:. 💾
• Media, Disk, +3, Drive A:, Eject — ejects the disk image currently in the +3's emulated drive A: — or from the emulated machine's perspective, ejects it. Note that any changes made to the image will not be saved. 😭
• Media, Disk, +3, Drive A:, Save — saves the disk image currently in the +3's drive A:.
• Media, Disk, +3, Drive A:, Save as... — saves the current state of the disk image currently in the +3's drive A: to a file. You will be prompted for a filename.
• Media, Disk, +3, Drive B:, Insert... — as above, but for the +3's drive B:. Fuse emulates drive B: as a second 3″ drive. Two drives, double the slay. 💿
• Media, Disk, +3, Drive B:, Eject — as above, but for drive B:.
• Media, Disk, +3, Drive B:, Save — as above, but for drive B:.
• Media, Disk, +3, Drive B:, Save as... — as above, but for drive B:.
• Media, Disk, Beta, Drive A:, Insert New — inserts a new (unformatted) disk into the emulated Beta drive A:. ✨
• Media, Disk, Beta, Drive A:, Insert..., Media, Disk, Beta, Drive A:, Eject, Media, Disk, Beta, Drive A:, Save, Media, Disk, Beta, Drive A:, Save as... — as above, but for the emulated Beta disk drive A:.
• Media, Disk, Beta, Drive A:, Write protect, Enable — enables the write protect tab for the image in Beta drive A:. 🔒
• Media, Disk, Beta, Drive A:, Write protect, Disable — disables the write protect tab for the image in Beta drive A:. 🔓
• Media, Disk, Beta, Drive B:, ..., Media, Disk, Beta, Drive C:, ..., Media, Disk, Beta, Drive D:, ... — as above, but for the remaining emulated Beta disk interface drives. So many drives, so little time. 👑
• Opus Discovery drives — as above, but for the emulated Opus Discovery drives:
  • Media, Disk, Opus, Drive 1, Insert New
  • Media, Disk, Opus, Drive 1, Insert...
  • Media, Disk, Opus, Drive 1, Eject
  • Media, Disk, Opus, Drive 1, Save
  • Media, Disk, Opus, Drive 1, Save as...
  • Media, Disk, Opus, Drive 1, Write protect, Enable
  • Media, Disk, Opus, Drive 1, Write protect, Disable
  • Media, Disk, Opus, Drive 2, ...
• +D drives — as above, but for the emulated +D drives:
  • Media, Disk, +D, Drive 1, Insert New
  • Media, Disk, +D, Drive 1, Insert...
  • Media, Disk, +D, Drive 1, Eject
  • Media, Disk, +D, Drive 1, Save
  • Media, Disk, +D, Drive 1, Save as...
  • Media, Disk, +D, Drive 1, Write protect, Enable
  • Media, Disk, +D, Drive 1, Write protect, Disable
  • Media, Disk, +D, Drive 2, ...
• Didaktik 80 drives — as above, but for the emulated Didaktik 80 drives:
  • Media, Disk, Didaktik 80, Drive A, Insert New
  • Media, Disk, Didaktik 80, Drive A, Insert...
  • Media, Disk, Didaktik 80, Drive A, Eject
  • Media, Disk, Didaktik 80, Drive A, Save
  • Media, Disk, Didaktik 80, Drive A, Save as...
  • Media, Disk, Didaktik 80, Drive A, Write protect, Enable
  • Media, Disk, Didaktik 80, Drive A, Write protect, Disable
  • Media, Disk, Didaktik 80, Drive B, ...
• DISCiPLE drives — as above, but for the emulated DISCiPLE drives:
  • Media, Disk, DISCiPLE, Drive 1, Insert New
  • Media, Disk, DISCiPLE, Drive 1, Insert...
  • Media, Disk, DISCiPLE, Drive 1, Eject
  • Media, Disk, DISCiPLE, Drive 1, Save
  • Media, Disk, DISCiPLE, Drive 1, Save as...
  • Media, Disk, DISCiPLE, Drive 1, Write protect, Enable
  • Media, Disk, DISCiPLE, Drive 1, Write protect, Disable
  • Media, Disk, DISCiPLE, Drive 2, ...
• Media, Cartridge, Timex Dock, Insert... — inserts a cartridge into the Timex 2068 dock. Warning bestie, this will cause the emulated machine to be changed to the TC2068 (if it wasn't already a 2068 variant) and reset. Glow-up + reboot combo. 🌟
• Media, Cartridge, Timex Dock, Eject — removes the cartridge from the Timex 2068 dock. Heads up: this will cause the emulated machine to be reset. 😳
• Media, Cartridge, Interface 2, Insert... — inserts a cartridge into the Interface 2 cartridge slot. This will cause the emulated machine to be reset and the cartridge loaded. 🎮
• Media, Cartridge, Interface 2, Eject... — removes the cartridge from the Interface 2 cartridge slot. This will cause the emulated machine to be reset.
• Media, IDE, Simple 8-bit, Master, Insert... — connects an IDE hard disk to the simple 8-bit interface's master channel. 🔌
• Media, IDE, Simple 8-bit, Master, Commit — causes any writes which have been done to the virtual hard disk attached to the simple 8-bit interface's master channel to be committed to the real disk, so that they survive the virtual disk being ejected. Basically a save-the-vibes button. 🫶
• Media, IDE, Simple 8-bit, Master, Eject — ejects the virtual hard disk from the simple 8-bit interface's master channel. Note that any writes to the virtual hard disk will be lost unless the Media, IDE, Simple 8-bit, Master, Commit option is used before the disk is ejected. Do not skip the commit, I'm begging. 😭
• Media, IDE, Simple 8-bit, Slave, Insert..., Media, IDE, Simple 8-bit, Slave, Commit, Media, IDE, Simple 8-bit, Slave, Eject — the same as the Media, IDE, Simple 8-bit, Master entries above, but for the simple 8-bit interface's slave channel.
• Media, IDE, ZXATASP, Master, Insert..., Media, IDE, ZXATASP, Master, Commit, Media, IDE, ZXATASP, Master, Eject, Media, IDE, ZXATASP, Slave, Insert..., Media, IDE, ZXATASP, Slave, Commit, Media, IDE, ZXATASP, Slave, Eject — the same as the Media, IDE, Simple 8-bit, Master entries above, but for the two channels of the ZXATASP interface. Whole lotta channels. 🔥

...and the IDE family keeps going, bestie, because of course it does 💅

• Media, IDE, ZXCF CompactFlash, Insert...
• Media, IDE, ZXCF CompactFlash, Commit
• Media, IDE, ZXCF CompactFlash, Eject — literally the same as the Media, IDE, Simple 8-bit, Master entries above, just pointed at the CompactFlash slot of the ZXCF interface. Same vibes, different slot 🎀
• Media, IDE, ZXMMC, Insert...
• Media, IDE, ZXMMC, Commit
• Media, IDE, ZXMMC, Eject — and again: same as the Media, IDE, Simple 8-bit entries above, but for the memory card slot on the ZXMMC interface 💖
• Media, IDE, DivIDE, Master, Insert...
• Media, IDE, DivIDE, Master, Commit
• Media, IDE, DivIDE, Master, Eject
• Media, IDE, DivIDE, Slave, Insert...
• Media, IDE, DivIDE, Slave, Commit
• Media, IDE, DivIDE, Slave, Eject — you guessed it: same as the Media, IDE, Simple 8-bit entries above, except these are for the two channels of the DivIDE interface 🔥
• Media, IDE, DivMMC, Insert...
• Media, IDE, DivMMC, Commit
• Media, IDE, DivMMC, Eject — one more time for the people in the back: same as Media, IDE, Simple 8-bit above, but for the memory card slot of the DivMMC interface 🌈
• Help, Keyboard... — pulls up a diagram of the Spectrum keyboard plus all the keywords you can generate with each key from (48K) BASIC. Under the GTK and Win32 UIs this pops open in a whole separate window and emulation just keeps vibing along in the background. With the other UIs, the picture stays onscreen (and the emulator pauses, obviously) until you hit Esc or Enter ✨
• Help, About... — shows you Fuse's version number. That's it. Short and sweet, we love a low-effort icon 💜

---

✨ KEY MAPPINGS ✨

Okay so when you're emulating the Spectrum, F1 to F10 are shortcuts for various menu items, exactly like we just described above. The alphanumeric keys (plus Enter and Space) map as-is onto the Spectrum keys. Everything else goes like this, bestie:

• Shift — emulated as Caps Shift
• Control, Alt, and Meta — emulated as Symbol Shift (and most other modifiers also map to this one too, no cap)
• Backspace — emulated as Caps–0 (Delete)
• Esc — emulated as Caps–1 (Edit)
• Caps Lock — emulated as Caps–2
• Cursor keys — emulated as Caps–5/6/7/8 (as appropriate, iykyk)
• Tab — emulated as Caps Shift–Symbol Shift (Extended Mode)

Some further punctuation keys are supported, if they actually exist on your keyboard — ,, ., /, ;, ', #, -, and =. These get mapped to the appropriate symbol-shifted keys on the Spectrum. 🦋

A list of keys that applies when you're using the file selection dialogs is given in the FILE SELECTION section below. Don't skip it 💅

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🎀 DISPLAY SIZE 🎀

Some of Fuse's UIs let you resize the emulated Spectrum's display. For the window-based ones (GTK, Win32 and Xlib), you resize the window by, well… resizing it. :-) Exactly how that goes down depends on your window manager; you may have to make the window over twice the width and height of the original size before it actually scales up. So dramatic 😭

Fuse attempts to keep the window square', but with some window managers this can mean the window will never resize at all. If you're experiencing that problem, the --no-aspect-hint` option may help. Slay a little fix for a little problem.

If you're using the SDL UI under X11 or GTK, the window will automatically resize to be the correct size for the graphics filter you've selected. Main character behaviour, honestly 👑

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🌸 GRAPHICS FILTERS 🌸

Fuse has the ability to apply essentially arbitrary filters between building its image of the Spectrum's screen and displaying it on the emulating machine's monitor. These filters can do various forms of smoothing, emulation of TV scanlines, and a whole bunch of other possibilities. Support for graphics filters varies between the different user interfaces, but there are two general classes: the GTK, Win32, Xlib and SDL user interfaces (and the saving of .png screenshots) support interpolating filters which use a palette bigger than the Spectrum's 16 colours, while the framebuffer user interface currently does not support filters at all. Rude of it, but okay 🙈

There's a further complication because the Timex machines have their high-resolution video mode with twice the horizontal resolution. To deal with this, Fuse treats these machines as having a `normal' display size which is twice the size of a normal Spectrum's screen, which means a different set of filters is available for these machines. Note that any of the double or triple-sizing filters are available for Timex machines only when using the SDL, Win32 or GTK user interfaces. Important detail, don't sleep on it 💖

The available filters, along with their short name used to select them from the command line, are:

• Timex half (smoothed) (half) and Timex half (skipping) (halfskip) — two Timex-machine specific filters which scale the screen down to half normal (Timex) size; that is, the same size as a normal Spectrum screen. The difference between these two is in how they handle the high-resolution mode: the smoothed version is an interpolating filter which averages pairs of adjacent pixels, while the skipping version is a non-interpolating filter which simply drops every other pixel. Pick your fighter ✨
• Normal (normal) — the simplest filter: just display one pixel for every pixel on the Spectrum's screen. Minimalist queen.
• Double size (2x) — scales the displayed screen up to double size.
• Triple size (3x) — scales the displayed screen up to triple size. Available when saving screenshots of non-Timex machines.
• Quadruple size (4x) — scales the displayed screen up to quadruple size.
• 2xSaI (2xsai), Super 2xSaI (super2xsai), SuperEagle (supereagle) — three interpolating filters which apply successively more smoothing. All three double the size of the displayed screen. Girl dinner of smoothing 🍓
• AdvMAME2x (advmame2x) — a double-sizing, non-interpolating filter which attempts to smooth diagonal lines.
• AdvMAME3x (advmame3x) — very similar to AdvMAME2x, except that it triples the size of the displayed screen. Available when saving screenshots of non-Timex machines.
• TV 2x (tv2x), TV 3x (tv3x), TV 4x (tv4x), Timex TV (timextv) — four filters which attempt to emulate the effect of television scanlines. The first is a double-sizing filter for non-Timex machines, the second is a similar triple-sizing filter, the third is a similar quadruple-sizing filter, while the last is a single-sizing filter for Timex machines (note that this means TV 2X and Timex TV produce the same size output). Nostalgia core 📺
• PAL TV 2x (paltv2x), PAL TV 3x (paltv3x), PAL TV 4x (paltv4x) — three filters which emulate a PAL television picture rather than a simple RGB-style pixel enlargement. They model composite-video style behaviour such as colour blending, reduced chroma resolution and softening between neighbouring pixels, while scaling the screen by 2×, 3× and 4× respectively.

These filters use Fuse's composite filter controls, allowing the image to be tuned with settings such as hue, saturation, contrast, brightness, sharpness, gamma, resolution, artifacts, fringing and bleed. Obsessed with a tunable glow-up 💜

• NTSC TV 2x (ntsctv2x), NTSC TV 3x (ntsctv3x), NTSC TV 4x (ntsctv4x) — three filters which emulate an NTSC television picture rather than a simple RGB-style pixel enlargement. They model composite-video effects such as colour bleeding, fringing, artifacting and softening between neighbouring pixels, while scaling the screen by 2×, 3× and 4× respectively.

These filters use the bundled snes_ntsc composite-video library by Shay Green ("blargg"). As with the PAL TV filters, the image can be tuned with the composite filter controls for hue, saturation, contrast, brightness, sharpness, gamma, resolution, artifacts, fringing and bleed. Shoutout to blargg 🫶

• Dot matrix (dotmatrix) — a double-sizing filter which emulates the effect of a dot-matrix display.
• Timex 1.5x (timex15x) — an interpolating Timex-specific filter which scales the Timex screen up to 1.5× its usual size (which is therefore 3× the size of a `normal' Spectrum screen).
• Timex 2x (timex2x) — a non-interpolating Timex-specific filter which scales the Timex screen up to 2× its usual size (which is therefore 4× the size of a `normal' Spectrum screen).
• HQ 2x (hq2x), HQ 3x (hq3x), HQ 4x (hq4x) — three filters which do high quality (but slow) antialiasing. Doubles and triples and quadruples the size of the displayed screen respectively. Gorgeous but she takes her time 💅

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🔥 THE EMULATED SPECTRUM 🔥

The emulated Spectrum is, by default, an unmodified 48K Spectrum with a tape player and ZX Printer attached. Oh, and apparently some magical snapshot load/save machine which is probably best glossed over for the sake of the analogy. :-) We don't question the magic machine, bestie, we just say thank you 🧚

To emulate different kinds of Spectrum, select the Machine, Select... menu option, or press F9.

The Spectrum emulation is paused when any dialogs appear. In the widget UI, it's also paused when menus or the keyboard picture are displayed. So it holds still for the photos, basically ✨

---

🖨️ PRINTER EMULATION 🖨️

The various models of Spectrum supported a range of ways to connect printers, three of which are supported by Fuse. Different printers are made available for the different models:

• 16, 48, TC2048, TC2068, TS2068 — ZX Printer
• 128/+2/Pentagon — Serial printer (text-only)
• +2A, +3 — Parallel printer (text-only)

If Opus Discovery, +D or DISCiPLE emulation is in use and printer emulation is enabled, text-only emulation of the disk interface's parallel printer interface is provided.

Any printout is appended to one (or both) of two files, depending on the printer — these default to printout.txt for text output, and printout.pbm for graphics (PBM images are supported by most image viewers and converters). These names can be changed with the --textfile and --graphicsfile options from the command line or configuration file. While the ZX Printer can only output graphically, simulated text output is generated at the same time using a crude sort of OCR based on the current character set (a bit like using SCREEN$). There is currently no support for graphics when using the serial/parallel output, though any escape codes used will be printed faithfully. (!) Iconic behaviour honestly, we stan a faithful escape code 🌈

Okay so — it's not a good idea to modify the printout.pbm file outside of Fuse if you want to continue appending to it. The header needs to have a certain layout for Fuse to be able to continue appending to it correctly, and the file will be overwritten if it can't be appended to. Don't touch it, bestie, I'm begging 😭

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🦋 ZXATASP AND ZXCF 🦋

ok so bestie, the ZXATASP and ZXCF interfaces are these two peripherals by Sami Vehmaa that just massively glow up what your Spectrum can do. More deets on both live on Sami's homepage, http://user.tninet.se/~vjz762w/, but here's the quick rundown.

The real ZXATASP ships with either 128K or 512K of RAM, plus the ability to hook up IDE hard disks and a CompactFlash card. The ZXCF comes with 128K, 512K or 1024K of RAM and can connect a CompactFlash card. From an emulation POV these two are honestly basically twins, because a CompactFlash card is logically just an IDE hard disk. rn Fuse's emulation is fixed at 512K of RAM in the ZXATASP and 1024K in the ZXCF.

To activate the ZXATASP, just select the ZXATASP interface option from the Options, Peripherals, Disk... dialog. The state of the upload and write protect jumpers is then controlled by the ZXATASP upload and ZXATASP write protect options. Same energy for the ZXCF — it's controlled by the ZXCF interface and ZXCF upload options (the ZXCF write protect is software controlled, fyi).

If you're using either the ZXATASP or ZXCF, you almost certainly wanna go investigate ResiDOS, the operating system designed for use with them. ResiDOS gives you facilities for using the extra RAM, accessing the mass storage devices, and a task manager that lets you switch between programs on the Spectrum basically instantly. Head to http://www.worldofspectrum.org/residos/ for more 💖

---

DIVIDE 👑

The DivIDE is another IDE interface for the Spectrum — full details at http://web.archive.org/web/20150302052256/http://baze.au.com/divide/. Activate it via the DivIDE interface option from the Options, Peripherals, Disk... dialog, and control the state of its write protect jumper via the DivIDE write protect option. If you're gonna be using the DivIDE, you'll probably want one of the firmwares available from the DivIDE homepage, bestie.

---

DIVMMC ✨

The DivMMC is an MMC interface for the Spectrum. Originally designed by Alessandro Dorigatti for the V6Z80P+ FPGA board as the fusion of DivIDE and ZXMMC+ interfaces, later assembled as an interface for real spectrums by Mario Prato. Currently there are variants with different RAM size, one/two memory card slots, optional kempston joystick, etc.

Activate it via the DivMMC interface option from the Options, Peripherals, Disk... dialog, and control the state of its EEPROM write protect jumper via the DivMMC write protect option. If you're gonna be using the DivMMC, you'll need to load the ESXDOS firmware at http://www.esxdos.org/ or use the ZX Spectrum +3e ROMs by Garry Lancaster.

You'll also need a HDF image to store the contents of the memory card. There are several tools to create and manipulate this file format, e.g. hdfmonkey at https://github.com/gasman/hdfmonkey.

---

🌈 SPECTRANET EMULATION 🌈

The Spectranet is an Ethernet network interface for the ZX Spectrum by Dylan Thomas. Activate it via the Spectranet option on the Peripherals preferences dialog, and control the state of its automatic page-in (disable) jumper via the Spectranet disable option. If you're gonna be using the Spectranet, you'll probably want one of the firmwares available from the Spectranet homepage (http://spectrum.alioth.net/doc/index.php) — which is also where you can find more info on using the interface.

ngl, installing the Spectranet firmware on Fuse is slightly more complicated than on a real machine, mostly because Fuse's emulation doesn't support DHCP. These instructions are correct as of 2012-01-26 — if you're using a later firmware than this, things may have changed slightly. 😭

First thing you gotta do: get a copy of the Spectranet installer as a .tap file (or similar). The installer is also available at the Spectranet site above.

Once you've got the installer, start Fuse and tick the Spectranet option from the Options, Peripherals, General... dialog, and the state of its write protect jumper is controlled via the Spectranet disable option. Once that's done, open the installer file (use the Media, Tape, Open... command rather than File, Open... to prevent autoloading) and enter the following commands from BASIC:

CLEAR 26999
LOAD "" CODE
RANDOMIZE USR 27000

The screen should turn blue and you'll see around 20 lines of message appearing as the firmware installs, starting with “Erasing sector 0” and finishing with “Restoring page B”, and you'll get the familiar 0 OK, 0: 1 at the bottom of the screen. iconic.

Now untick the Spectranet disable option from the Options, Peripherals, General... dialog and reset the Spectrum. You should see a very brief blue status screen, before the regular copyright screen appears with some Spectranet information at the top — there should be four status lines, starting with “Alioth Spectranet” and ending with the Spectranet's IP address (which will be 255.255.255.255 at this stage).

Now trigger an NMI (the Machine / NMI menu option) and you should get a white on blue Spectranet NMI menu with five options.

Select [A] Configure network settings — this should lead you to another menu, which will scroll off the top of the screen; don't worry about this for now.

You'll now need to set various options:

• [A] Enable/disable DHCP — select N
• [B] Change IP address — enter the IP address of the machine you are running Fuse on.
• [C] Change netmask — enter the appropriate netmask for the IP address you selected above. If that doesn't mean anything to you, try 255.255.255.0
• [D] Change default gateway — enter the appropriate gateway address. If you don't know any better, enter the IP address of your router.
• [E] Change primary DNS — enter the address of your DNS server. If you don't know any better, use Google's public DNS server, 8.8.8.8.

There is no need to change options [F] or [G], but do select:

• [H] Change hostname — enter a hostname for the Spectranet-enabled machine. It doesn't really matter what you enter here — it's mostly useful just to replace the junk default name so you can see what you've entered for the other settings.

Your screen should now look something like this:

Current configuration
───────────────────────────────────────
Use DHCP           : No
IP address         : 192.168.000.002
Netmask            : 255.255.255.000
Default gateway    : 192.168.000.001
Primary DNS        : 192.168.000.001
Secondary DNS      : 255.255.255.255
Hardware address   : FF:FF:FF:FF:FF:FF
Hostname           : fuse
<menu options>

If everything looks correct, select [I] Save changes and exit (you'll see a brief “Saving configuration...” message) followed by [E] Exit, at which point you'll be returned to BASIC.

Now type the following commands:

%cfgnew
%cfgcommit

Which will show the standard 0 OK, 0:1 at the bottom of the screen.

Reset the Spectrum again and you'll see the same four line status display, but this time with your IP address on the last line. 🎀

Congratulations! You have now installed the Spectranet firmware. To save having to go through all that every time you start Fuse, save a .szx snapshot at this point, and load that in every time you want to use the Spectranet. lowkey genius.

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💜 TTX2000S EMULATION 💜

Fuse supports emulating the OEL/Volex TTX2000S teletext adaptor with 16K and 48K machines.

The interface has four tuning presets and extracts teletext signals from the vertical blanking interval of the selected television channel. These teletext signals are emulated by means of a simple TCP socket interface provided by an external server application. An example server written in Python is available from https://github.com/ZXGuesser/teletext-packet-server

The default address for the four packet servers is 127.0.0.1 (loopback address), ports 19761 to 19764. Connections can also be made to other computers on a fast LAN by IP address or hostname. Connecting a packet server via the internet is not recommended. 🙈

Only one connection is active at a time. Changing channel preset on the emulated interface closes any active connection and opens a new connection to the appropriate server. The same packet server can be set for multiple tuning presets.

Heads up bestie: a limitation of the TTX2000S ROM means that it only decodes the first 12 lines of a teletext signal. This can be fixed by entering BASIC and executing POKE 23394,33 then re-entering the teletext ROM with RANDOMIZE USR 23500. Alternatively just use teletext packet sources with 12 lines per field or fewer.

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🌸 FILE SELECTION 🌸

The way you select a file (whether snapshot or tape file) depends on which UI you're using. So firstly, here's how to use the GTK file selector.

The selector shows the directories and files in the current directory in two separate subwindows. If either list is too big to fit in the window, you can use the scrollbar to see the rest (by dragging the slider, for example), or you can use Shift–Tab (to move the keyboard focus to a subwindow) and use the cursor keys. To change directory, double-click it.

To choose a file to load you can either double-click it, or click it then click Ok. Or click Cancel to abort.

If you're using the keyboard, probably the easiest way to use the selector is to just ignore it and type in the name. This isn't as irksome as it sounds, since the filename input box has filename completion — type part of a directory or file name, then press Tab. It should complete it. If it was a directory, it moves to that directory; if the completion was ambiguous, it completes as much as possible, and narrows the filenames shown to those which match. You should press Enter when you've finished typing the filename, or Esc to abort.

Now, if you're using the widget UI — the one using the Spectrum font — the selector works a bit differently. The files and directories are all listed in a single two-column-wide window (the directories are shown at the top, ending in /) — the names may be truncated onscreen if they're too long to fit.

To move the cursor, you can either use the cursor keys, or the Spectrum equivalents 5/6/7/8, or (similarly) h/j/k/l. For faster movement, the Page Up, Page Down, Home, and End keys are supported and do what you'd expect. To select a file or directory, press Enter. To abort, press Esc.

With both selectors, do bear in mind that all files are shown, whether Fuse would be able to load them or not. 👀

💖 MONITOR/DEBUGGER 💖

---

okay so first thing bestie: almost all of this section is GTK-only. If you're on one of the widget user interfaces, you get a very basic monitor that shows the current values of the registers and lets you single step through execution or continue. That's it. no fancy panes, no drama 💅

If you are on the GTK user interface, Fuse has a moderately powerful, completely transparent monitor/debugger, and you can turn it on via the Machine, Debugger... menu option. A debugger window pops up showing the current state of the emulated machine: the top-left pane shows the current state of the Z80 and the last bytes written to any emulated peripherals. The bottom-left pane lists any active breakpoints. Moving right, the next pane shows where the Spectrum's 64K memory map is at — the W? and C? tell you whether each displayed chunk is writable or contended respectively. Fuse tracks the memory mapping of the overall address space in 2KB chunks but will summarise the mapped pages where they are part of the same page of the underlying memory source (e.g. 8KB page sizes in the Spectrum 128K and 4KB pages in the Timex clones' DOCK and EXROM banks).

The next pane to the right has a disassembly, which by default starts at the current program counter, although this can be modified either by the disassemble command (see below) or by dragging the scrollbar next to it. The next pane shows the current stack, and the final pane any events which are due to occur and could affect emulation. Any of these panes can be removed by use of the View menu. Below the displays are an entry box for debugger commands, and five buttons for controlling the debugger:

• Evaluate — Evaluate the command currently in the entry box.
• Single Step — Run precisely one Z80 opcode and then stop emulation again.
• Continue — Restart emulation, but leave the debugger window open. Note that the debugger window will not be updated while emulation is running.
• Break — Stop emulation and return to the debugger.
• Close — Close the debugger window and restart emulation.

Double-clicking on an entry in the stack pane will cause emulation to run until the program counter reaches the value stored at that address, while double-clicking on an entry in the events pane will cause emulation to run until that time is reached.

The main power of the debugger is via the commands entered into the entry box, which are similar in nature (but definitely not identical to or as powerful as) to those in gdb(1). In general, the debugger is case-insensitive, and numbers will be interpreted as decimal, unless prefixed by 0x when they will be interpreted as hex. Each command can be abbreviated to the portion not in curly braces.

• ba{se} number — Change the debugger window to display output in base number. Available values are 10 (decimal) or 16 (hex).
• br{eakpoint} [address] [if condition] — Set a breakpoint to stop emulation and return to the debugger whenever an opcode is executed at address and condition evaluates true. If address is omitted, it defaults to the current value of PC.
• br{eakpoint} p{ort} (re{ad}|w{rite}) port [if condition] — Set a breakpoint to trigger whenever IO port port is read from or written to and condition evaluates true.
• br{eakpoint} (re{ad}|w{rite}) [address] [if condition] — Set a breakpoint to trigger whenever memory location address is read from (other than via an opcode fetch) or written to and condition evaluates true. Address again defaults to the current value of PC if omitted.
• br{eakpoint} ti{me} time [if condition] — Set a breakpoint to occur time tstates after the start of every frame, assuming condition evaluates true (if one is given).
• br{eakpoint} ev{ent} area:detail [if condition] — Set a breakpoint to occur when the event specified by area:detail occurs and condition evaluates to true. The events which can be caught are:
  • beta128:page, beta128:unpage — The Beta 128 interface is paged into or out of memory respectively.
  • didaktik80:page, didaktik80:unpage — The Didaktik 80 interface is paged into or out of memory respectively.
  • disciple:page, disciple:unpage — The DISCiPLE interface is paged into or out of memory respectively.
  • divide:page, divide:unpage — The DivIDE interface is paged into or out of memory respectively.
  • divmmc:page, divmmc:unpage — The DivIDE interface is paged into or out of memory respectively.
  • if1:page, if1:unpage — The Interface 1 shadow ROM is paged into or out of memory.
  • multiface:page, multiface:unpage — The Multiface One/128/3 is paged into or out of memory respectively.
  • opus:page, opus:unpage — The Opus Discovery is paged into or out of memory respectively.
  • plusd:page, plusd:unpage — The +D interface is paged into or out of memory respectively.
  • rzx:end — An RZX recording finishes playing.
  • speccyboot:page, speccyboot:unpage — The SpeccyBoot interface is paged into or out of memory.
  • spectranet:page, spectranet:unpage — The Spectranet interface is paged into or out of memory.
  • tape:play, tape:stop — The emulated tape starts or stops playing.
  • uspeech:page, uspeech:unpage — The µSpeech interface is paged into or out of memory.
  • zxatasp:page, zxatasp:unpage — The ZXATASP interface is paged into or out of memory.
  • zxcf:page, zxcf:unpage — The ZXCF interface is paged into or out of memory.

In all cases, the event can be specified as area:* to catch all events from that area.

• cl{ear} [address] — Remove all breakpoints at address or the current value of PC if address is omitted. Port read/write breakpoints are unaffected.
• com{mmands} id <newline> — Set things such that the specified debugger commands will be automatically executed when breakpoint id is triggered. There is currently no user interface for entering multi-line debugger commands, so the only way to specify this command is on the command-line via the --debugger-command option.

com{mmands} id <newline>
<debugger command> <newline>
<debugger command> <newline>
...
end

• cond{ition} id [condition] — Set breakpoint id to trigger only when condition is true, or unconditionally if condition is omitted.
• co{ntinue} — Equivalent to the Continue button.
• del{ete} [id] — Remove breakpoint id, or all breakpoints if id is omitted.
• di{sassemble} address — Set the centre panel disassembly to begin at address.
• ex{it} [expression] — Exit the emulator immediately, using the exit code resulting from the evaluation of expression, or 0 if expression is omitted.
• fi{nish} — Exit from the current CALL or equivalent. This isn't infallible: it works by setting a temporary breakpoint at the current contents of the stack pointer, so will not function correctly if the code returns to some other point or plays with its stack in other ways. Also, setting this breakpoint doesn't disable other breakpoints, which may trigger before this one. In that case, the temporary breakpoint remains, and the continue command can be used to return to it.
• i{gnore} id count — Do not trigger the next count times that breakpoint id would have triggered.
• n{ext} — Step to the opcode following the current one. As with the finish command, this works by setting a temporary breakpoint at the next opcode, so is not infallible.
• o{ut} port value — Write value to IO port port.
• pr{int} expression — Print the value of expression to standard output.
• se{t} address value — Poke value into memory at address.
• se{t} $variable value — Set the value of the debugger variable variable to value.
• se{t} area:detail value — Set the value of the system variable area:detail to value. The available system variables are listed below.
• s{tep} — Equivalent to the Single Step button.
• t{breakpoint} [options] — This is the same as the breakpoint command in its various forms, except that the breakpoint is temporary: it will trigger once and once only, and then be removed.

Addresses can be specified in one of two forms: either an absolute address, specified by an integer in the range 0x0000 to 0xFFFF, or as a source:page:offset combination, which refers to a location offset bytes into memory bank page, independent of where that bank is currently paged into memory. RAM and ROM pages are indicated, respectively, by RAM and ROM sources (e.g. offset 0x1234 in ROM 1 is specified as ROM:1:0x1234). Other available sources are: Betadisk, Didaktik 80 RAM, Didaktik 80 ROM, DISCiPLE RAM, DISCiPLE ROM, DivIDE EPROM, DivIDE RAM, DivMMC EPROM, DivMMC RAM, If1, If2, Multiface RAM, Multiface ROM, Opus RAM, Opus ROM, PlusD RAM, PlusD ROM, SpeccyBoot, Spectranet, Timex Dock, Timex EXROM, uSource, uSpeech, ZXATASP and ZXCF. Please, note that spaces in memory sources should be escaped, e.g., break Didaktik\ 80\ ROM:0:0x1234. The 48K machines are treated as having a permanent mapping of page 5 at 0x4000, page 2 at 0x8000 and page 0 at 0xC000; the 16K Spectrum is treated as having page 5 at 0x4000 and no page at 0x8000 and 0xC000.

okay so literally anywhere the debugger wants a number — except when it wants a breakpoint id, that one's special — you can drop in a whole numeric expression instead 🧮. It's C syntax but the ✨restricted✨ edition. Same rules apply for conditional breakpoints, where 0 = false and literally anything else = true. No cap.

Inside these expressions you've got: integer constants (everything is done in integers, we're not doing float math here bestie 💅), system variables, debugger variables, parentheses, the five standard numeric operations (+, -, *, /, %), the shift operators << and >>, the (non-)equality operators == and !=, the comparison operators >, <, >= and <=, bitwise and (&), or (|) and exclusive or (^), and logical and (&&) and or (||).

Square brackets ([ and ]) dereference a value for you 🫶 — like, [0x4000] gives you the value of the first byte of the screen. iconic.

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🌸 System variables 🌸

System variables use an area:detail syntax. Here's the whole roster, no skips:

• ay:current — the current AY-3-8912 register.
• divmmc:control — the last byte written to the DivMMC control port.
• spectrum:frames — the frame count since reset. > heads up bestie: this one is read-only, you can't write to it, periodt.
• tape:microphone — the current level of the tape input connected to the EAR port. > also read-only, no writing, sorry 🥺.
• ula:last — the last byte written to the ULA. > yep, read-only too.
• ula:mem1ffd — the last byte written to the memory control port used by the ZX Spectrum +2A/3; normally addressed at 0x1ffd, hence the name.
• ula:mem7ffd — the last byte written to the primary memory control port used by the ZX Spectrum 128 and later; normally addressed at 0x7ffd, hence the name.
• ula:tstates — the number of tstates since the last interrupt.
• z80: register name — the value of the specified register. Both 8-bit registers and 16-bit register pairs are supported. The MEMPTR / WZ hidden register is also supported. The (presumable) Q hidden register is also supported. 👑
• z80:im — the current interrupt mode of the Z80.
• z80:iff1, z80:iff2 — 1 if the specified interrupt flip-flop is currently set, or 0 if it is not set.

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🔍 THE POKE FINDER 🔍

The poke finder is a tool made to make finding pokes for games (infinite lives and all that) a lil bit easier 💖 — it's basically the same energy as the Lifeguard utility that used to ship with the Multiface. How it works: it keeps a list of locations where your current number of lives (or whatever) might be stored, and it can yeet from that list any location that doesn't hold a value you specify. so satisfying to watch the list shrink ngl.

The poke finder dialog has an entry box where you type the value to search for, a count of how many possible locations are left, and — if there are fewer than 20 possible locations — a list of those locations in page:offset format. The five buttons do this:

• Incremented — removes from the list of possible locations all addresses which have not been incremented since the last search.
• Decremented — removes from the list of possible locations all addresses which have not been decremented since the last search.
• Search — removes from the list of possible locations all addresses which do not contain the value specified in the Search for field.
• Reset — resets the poke finder so that all locations are considered possible again.
• Close — closes the dialog. > note that this does not reset the current state of the poke finder, so it'll be exactly where you left it next time 👀.

Double-clicking on an entry in the list of possible locations sets a breakpoint to trigger whenever that location gets written to. chef's kiss.

An example might make this click, so let's go 🎮. We're using the 128K version of Gryzor. Load the game, define keys to suit, start playing. Immediately pause the game and bring up the poke finder dialog. We note we currently have 6 lives, so enter 6 into the Search for field and click Search. This reduces the possible locations to around 931 (you might get a slightly different number depending on exactly when you paused the game — no two vibes are identical). Play along a bit, then (deliberately 😈) lose a life. Pause again. We now have 5 lives, so swap the 6 in the Search for field for a 5 and click Search again. This narrows the list of possible locations down to exactly one: page 2, offset 0x00BC. This is the only location in memory that stored 6 when we had 6 lives and 5 when we had 5 lives, so it's pretty likely that's where the lives count lives 🏠. Double-clicking the 2:0x00BC entry in the dialog sets the appropriate breakpoint (you may want to open the debugger here to confirm — go off). Play a bit more. When you next lose a life, emulation stops with PC at 0x91CD. Scrolling up a few addresses in the debugger's disassembly pane shows that a value was loaded from 0x80BC (our hypothetical lives counter), decremented, and then stored back to 0x80BC — which looks very much like the code that reduces the number of lives. Now we can use the debugger to replace the decrement with a NOP (set 0x91c9 0), and playing the game some more after that reveals it worked and we now have infinite lives. ✨ slay ✨

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💾 THE POKE MEMORY 💾

Fuse supports multiface POKEs, which let you modify specific memory addresses to cheat (infinite lives, infinite ammo, etc.). living your best life fr fr.

The poke memory dialog has a list of recently loaded POKEs and some entry boxes for adding custom ones:

• Bank — sets the 128K memory bank (values 0 to 7) or the current memory mapping (value 8 or blank).
• Address — the memory address to modify. Values in range 16384 to 65535 for 48K memory mode, or 0 to 65535 for 128K memory banks. The GTK UI also accepts hex addresses 💅.
• Value — the new value for that address, in range 0 to 255. Value 256 means “Prompt to the user later”.

You can load POKEs from an external file via the File, Open... menu option, or by drag-and-drop in the GTK and Win32 UIs 🫳✨. After you load a snapshot or tape, Fuse will try to automatically locate a POK file with the same file name. So if we open GAME.TAP, Fuse will try to open GAME.POK and POKES/GAME.POK. More deets about this file format live at http://www.worldofspectrum.org/POKformat.txt 📖.

POKEs loaded in the list can be activated or deactivated whenever you want, and they'll stay in memory until a machine reset.

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📀 THE .DSK FORMAT 📀

So in general, disk images for the +3 Spectrum get thought of as being in DSK format. But lowkey that's a slight oversimplification — there are actually two similar, but not identical, DSK formats 👯. (You can spot the difference by doing head -1 dskfile: one format starts with MV - CPCEMU and the other starts with EXTENDED.)

Fuse supports both the CPCEMU and EXTENDED formats. we contain multitudes 💜

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🌈 BETA 128 EMULATION 🌈

Fuse supports Betadisk emulation in its Pentagon and Scorpion emulation, and also under 48K, TC2048, 128K and +2 (but not +2A) emulation, if the Beta 128 interface option from the Options, Peripherals, Disk... dialog is enabled. When that option is used in 48K or TC2048 emulation, the Beta 128 auto-boot in 48K machines option additionally controls whether the machine boots directly into the TR-DOS system 🥾. See the DISK FILE FORMATS section for more details on supported disk file formats.

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🗣️ CURRAH µSPEECH 🗣️

The Currah µSpeech interface is an allophone speech synthesiser. This interface uses a SP0256-AL2 chip that has an internal ROM with commands to make english allophones 🎙️. Fuse needs this ROM named sp0256-al2.rom in your ROMs directory, and its CRC-32 is b504ac15.

An alternative authorised ROM is distributed by Joe Zbiciak with CRC-32 df8de0b0. In this case, the bit ordering in data bytes is reversed and needs to be adjusted. ⚠️ so heads up on that one.

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🖨️ OPUS DISCOVERY EMULATION 🖨️

By default, Fuse emulates the Opus Discovery interface with the optional 2k RAM expansion and a second 40 track single sided disk drive. See the DISK FILE FORMATS section for more details on supported disk file formats. The Opus Discovery's printer port is also emulated, output only. (See the PRINTER EMULATION section for more details.) The Opus Discovery may only be used with 16K, 48K, 128K, TC2048 and +2 (not +2A) emulation. To access disks, use the same syntax as Interface 1 and Microdrives. simple as that bestie 💫

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➕ +D EMULATION ➕

Fuse supports emulating the +D disk and printer interface. See the DISK FILE FORMATS section for more details on supported disk file formats. The +D's printer port is emulated. (See the PRINTER EMULATION section for more details.) The +D may only be used with 48K, 128K and +2 (not +2A) emulation. To access disks, you'll first need to load G+DOS, by inserting a disk containing the DOS file (+SYS) and entering “RUN”. Once DOS is loaded, you can load to/from +D disks by prefixing filenames with dn, where n is the number of the drive in use. For example, LOAD d1"myfile" would load the file named myfile from the emulated drive 1. Microdrive syntax may also be used. 👑

To save a snapshot, choose the Machine, NMI menu option, then press 4 to save a 48K snapshot, or 5 to save a 128K snapshot. When saving a 128K snapshot, you must then press Y or N to indicate whether the screen changed while saving the snapshot, to finish saving. You can also choose 3 to save a screenshot to disk. Holding Caps Shift together with any of these options will cause the +D to save to the other drive to the one used last 🌀.

Options 1 and 2 allow screenshots to be printed (in monochrome, in normal and large formats respectively) if printer emulation is enabled. For saving and loading of snapshots, and saving of screenshots to disk, G+DOS must be loaded first — but printing of screenshots can be performed without loading G+DOS. ✨

Finally, X will return from the NMI menu.

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🎀 DIDAKTIK 80 EMULATION 🎀

Fuse supports Didaktik 80 (and Didaktik 40) emulation. It emulates the original version of the Didaktik 80, running MDOS 1 and with a WD2797 floppy controller. See the DISK FILE FORMATS section for more details on supported disk file formats. The Didaktik 80 may only be used with 16K, 48K and TC2048 emulation. To press the Didaktik 80's SNAP button, choose the Machine, Didaktik SNAP menu option. 📸

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💾 DISCIPLE EMULATION 💾

okay so bestie, Fuse totally supports emulating the DISCiPLE disk and printer interface 🎀 — but heads up, it does not currently support emulation of the Sinclair Network, and it also doesn't support emulation of a DISCiPLE attached to a 128K machine. sad but true 😭. Slide over to the DISK FILE FORMATS section for the tea on which disk file formats are supported — spoiler: they're the exact same ones as for +D emulation described above. The DISCiPLE's printer port is emulated tho (see the PRINTER EMULATION section for the deets 💅). Also the DISCiPLE may only be used with 48K emulation at present, periodt.

To actually get at your disks, you'll first need to load GDOS — insert a disk containing the DOS file (SYS) and type in "RUN". Once DOS is loaded, you can load to/from DISCiPLE disks by prefixing filenames with dn where n is the number of the drive in use. Like, for example, LOAD d1"myfile" would load the file named myfile from the emulated drive 1. you could also just use Microdrive syntax, that works too ✨.

Snapshots can be saved in a similar manner to that of the +D as described above, but — and this is the important part — GDOS on the DISCiPLE contains a bug which causes corruption as soon as the NMI button is pressed 🫠. That messes with saving of snapshots, and also loading of snapshots that were originally saved with a +D or SAM Coupé. And like, it will cause corruption even when a screenshot is printed, or if the menu is never even entered in the first place (due to Caps Shift not being pressed down, as is required for the DISCiPLE), provided that GDOS is loaded. This bug is not present in G+DOS on the +D. (Note: this was caused by saving/restoring the AF register twice in the NMI handler, where both AF and the AF' shadow register should have been saved/restored.)

The NMI button works slightly differently on the DISCiPLE than on the +D. Caps Shift must be held down whilst pressing the NMI button, and there is no X option to exit the menu. Also, printing of screenshots requires GDOS to be loaded. Depending on the UI that you're using, holding down Caps Shift whilst choosing the Machine, NMI menu option may be slightly tricky, or even impossible 😩. For the GTK UI, ensure that the Shift key is held before entering on the Machine menu. For the widget UI, it does not seem possible to perform this action. rip.

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📀 DISK FILE FORMATS 📀

Fuse supports several disk image formats in its +D, Didaktik, DISCiPLE and Beta 128 emulation. icon behavior fr.

✨ For reading: ✨

• .UDI — Ultra Disk Image; for specification please see http://faqwiki.zxnet.co.uk/wiki/UDI_format or http://zxmak.chat.ru/docs.htm

This is the only image format which can store all the relevant information of the recorded data on a magnetic disk, so it can be used for any non standard disk format. Fuse can read all extended track types too (mixed FM/MFM, or tracks with WEAK data or even compressed tracks too). it's giving main character energy 👑

• .FDI — UKV Spectrum Debugger disk image format.
• .MGT .IMG — DISCiPLE/+D file formats.
• .SAD — For compatibility with SAM Coupé disk images using these formats. Note that SAM Coupé .DSK images share the same format as .MGT.
• .D80 .D40 — Didaktik 80 and Didaktik 40 file formats.
• .TRD — TR-DOS disk image. TRD and SCL sectors are loaded interleaved, therefore you might experience problems with TR-DOS ROMs that use the turbo format (sequential sectors); for detailed information please see http://web.archive.org/web/20070808150548/http://www.ramsoft.bbk.org/tech/tr-info.zip
• .SCL — A simple archive format for TR-DOS disk files. For specification please see http://www.zx-modules.de/fileformats/sclformat.html
• .TD0 — Teledisk image format; Fuse supports only files which do not use the "Advanced Compression" option. Detailed description found in http://www.classiccmp.org/dunfield/img54306/td0notes.txt and https://web.archive.org/web/20130116072335/http://www.fpns.net/willy/wteledsk.htm
• .DSK — CPC disk image format; Fuse supports the plain old and the new extended CPC format too. Further information please see the THE .DSK FORMAT section and the CPCEMU manual section 7.7.1 http://www.cpc-emu.org/linux/cpcemu_e.txt or the http://www.cpctech.org.uk/docs/extdsk.html
• .OPD .OPU — Opus Discovery file formats.

Fuse supports most of the above formats for writing: .UDI .FDI .MGT .IMG .SAD .D80 .D40 .TRD .SCL .OPD .OPU .DSK (only the old CPC format). no cap 💯.

You can save disk images with any output format, just select the appropriate extension. (e.g. elite3.udi to save as an UDI file). If the appropriate libraries were available when libspectrum(3) was compiled, than Fuse will try to create UDI images with compressed tracks to save disk space. There is a .LOG image format for debugging purpose. This is a plain text file that contains three dumps of the loaded disk image at different details. Not all image formats can store all disk images. You cannot save a disk image with an inappropriate format that loses some information (e.g. variable track length or sector length). bestie don't do it, that info is gone 🫶.

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🌀 WEAK DISK DATA 🌀

Some copy protections have what is described as weak/random data. Each time the sector is read one or more bytes will change, the value may be random between consecutive reads of the same sector. lowkey chaotic tbh 😵‍💫. Two disk image formats (Extended DSK and UDI) can store this type of data. Fuse can read and use weak sector data from EDSK and UDI files when present, and can save back weak sector data to UDI image format. slay ✨.

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🎬 MOVIE RECORDING 🎬

Fuse can save movies with sound in a specific file format (FMF). This recording is very fast, and has a moderate size, but you need to use the fmfconv(1) program in fuse-utils(1) to convert into regular video and/or audio files. The --movie-compr option allows you to set the compression level to None, Lossless or High. If zlib(3) is not available, only None is valid. The default when Zlib is available is Lossless. Recording a movie may slow down emulation, so if you experience performance problems, you can try to set compression to None 💅.

Fuse records every displayed frame, so by default the recorded file has about 50 video frame per second. A standard video has about 24–30/s framerate, so if you set Options/General/Frame rate 1:n or the equivalent --rate command line option to 2 than recording frame rate reduces about 25/s. The exact frame rate depends on the Z80 clock frequency which varies depending on the specific emulated machine. it's giving very specific and we love that for us 🌸.

Note: You can see all of the "gfx" effects only if the Fuse frame rate option is set to 1, but in most cases you can safely use 2. Also, movie recording stops if the emulated machine is changed. 🙈

The recorded sound sampling rate and the channel number is equal with the Fuse generated sound sampling rate (44100 Hz by default) and channel number (mono by default). The common sampling frequencies in standard video files are 44100 Hz and 48000 Hz. If you use --sound-freq command line option you can change the frequency.

You can record stereo sound if you use AY stereo separation or the equivalent --separation command line switch. obsessed 🎧.

You can use fmfconv(1) to convert recorded movie file into a standard video file.

Examples

fuse --movie-start output.fmf --rate 2 --sound-freq 44100 --separation ACB

start video recording about 25/s video frame rate and 44100 Hz sampling frequency stereo sound default compression level. iconic 🎥.

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🗜️ COMPRESSED FILES 🗜️

Assuming the appropriate libraries were available when libspectrum(3) was compiled, snapshots, tape images, dock cartridges and input recording files (RZX) can be read from files compressed with bzip2(3), gzip(3) or zip(3) just as if they were uncompressed. In the zip case, only the first supported file found inside the archive is loaded. There is currently no support for reading compressed +3, DISCiPLE/+D or Beta disk images. ngl that last bit is a lil sad but we move 💜.

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💀 BUGS 💀

• The poke finder can't search outside normal RAM.
• The libao file output devices not work properly with the GTK UI. No error reporting, but the created file does not contain any sound data. If you use a weak machine alsa09 makes a lot of clicks and pops and will output ALSA: underrun, at least 0ms. error messages.

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📁 FILES 📁

• $XDG_CONFIG_HOME/fuse-emulator/fuserc — On Unix systems this is the per-user configuration file of Fuse. Writing configuration always goes to the XDG location.
• ~/.config/fuse-emulator/fuserc — If $XDG_CONFIG_HOME is unset, this is the location of the configuration file.
• $HOME/.fuserc — If neither of previous files exist, reading falls back to this file as it was the default location until Fuse 1.7.0.
• %USERPROFILE%\fuse.cfg — On Windows system this is the per-user configuration file of Fuse.

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🦋 SEE ALSO 🦋

bzip2(3), fmfconv(1), fuse-utils(1), gzip(3), libspectrum(3), ogg123(1), xspect(1), xzx(1), zip(3).

The comp.sys.sinclair Spectrum FAQ, at http://www.worldofspectrum.org/faq/index.html. go read it bestie, it's giving lore 📚✨.

💖 AUTHOR 💖

okay so bestie, this emulator was NOT built by one person in a basement (well… maybe a little of that 😭). it's a whole squad effort, and we're gonna give every single one of them their flowers. 🌸

• Philip Kendall (philip-fuse@shadowmagic.org.uk) — the main character of this whole operation. 👑
• Matan Ziv-Av wrote the SVGAlib and framebuffer UIs, the glib replacement code, and did some work on the OSS-specific sound code and the original widget UI code. multitasking queen ✨
• Russell Marks wrote the sound emulation and OSS-specific sound code, the joystick emulation, some of the printer code, and the original version of this man page. so like… this page you're reading? his fault. 💅
• John Elliott's lib765 and libdsk libraries were used for the original +3 disk and disk image support.
• Ian Collier wrote the ZX Printer emulation (for xz80).
• Darren Salt wrote the original versions of the code for +3 emulation, SLT support, MITSHM support (for the Xlib UI), TZX raw data blocks, RZX embedded snapshots and compression, the Kempston mouse emulation and made many improvements to the widget code. like, sir, that's a LOT. 🫶
• Alexander Yurchenko wrote the OpenBSD/Solaris-specific sound code.
• Fredrick Meunier wrote the TC2048, TS2068, Pentagon and Spectrum SE support, the CoreAudio sound code, as well as maintaining the OS X port and importing the graphics filter code.
• Ludvig Strigeus and The ScummVM project wrote the original graphics filter code.
• Dmitry Sanarin wrote the original Beta disk interface emulation (for Glukalka).
• Witold Filipczyk wrote the TC2068 support.
• Matthew Westcott wrote the AY logging code and the DivIDE emulation.
• Marek Januszewski wrote various bits of code to make Fuse work under Win32, including the DirectDraw user interface.
• Sergio Baldoví made many improvements to the Win32 UI.
• Stuart Brady wrote the DISCiPLE and +D emulation, Scorpion emulation and the HP-UX sound code.
• Garry Lancaster wrote the 8-bit IDE, ZXATASP and ZXCF interface emulations.
• Gergely Szasz wrote the Interface 1, Microdrive emulation and Didaktik 80 emulation, the PAL TV scalers, the TV 3x scaler, the movie logging code, the ALSA and libao sound code, the µPD765 disk controller used in the +3 and made many improvements to the widget code. okay this person literally did everything?? ate and left no crumbs 🔥
• Michael D Wynne wrote the original Opus disk interface emulation (for EightyOne).
• Patrik Persson wrote the SpeccyBoot emulation.

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and that's the whole page, bestie!! 🎉 you made it to the very end, which honestly deserves a little round of applause for you specifically 👏🫶

so like, the vibes for this edition: it's version 1.9.1, dated 25th July, 2026, and it belongs to the fuse(1) page — the man page, not the person (we love both tho 💜). go emulate something iconic, babe. no cap. ✨🌈🎀