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Oricutron - RetroBIOS
Type standalone
Classification Other
Source https://github.com/pete-gordon/oricutron
Upstream https://www.petergordon.org.uk/oricutron/
Version 1.2.0
Profiled 2026-08-08
Cores oricutron
Systems oric, oricatmos
Source analysis

gui_images:

- **source_ref:** gui.c:100-117 (gimgs table), gui.c:425-492 (gimg_load), gui.c:2464-2466 (init_gui)
- **lookup:** program directory + IMAGEPREFIX, which is images/ everywhere except AmigaOS and the emscripten build (system.h:38-68)
- **validation:** uncompressed 24-bit BMP, one plane, at the exact width and height declared in the table
- **fatal:** True
- **note:** init_gui returns SDL_FALSE on the first image it cannot read and the emulator exits (main.c:1416-1420). The set ships in the source tree and in the binary releases, and packagers install it beside the...
**files:**

- statusbar.bmp
- disk_ejected.bmp
- disk_idle.bmp
- disk_active.bmp
- disk_modified.bmp
- disk_modactive.bmp
- tape_ejected.bmp
- tape_pause.bmp
- tape_play.bmp
- tape_stop.bmp
- tape_record.bmp
- avirec.bmp
- gfx_oric1kbd.bmp
- gfx_atmoskbd.bmp
- gfx_pravetzkbd.bmp

**conditional_entries:**

    - **note:** gfx_oric1kbd.bmp sits behind WWW_NO_ORIC1 and gfx_pravetzkbd.bmp behind WWW_NO_PRAVETZ (gui.c:112-118, gui.h:114-120), both of which only cut down the emscripten build. A native build carries all fift...
**non_fatal:**

- filename: winicon.bmp, source_ref: gui.c:2306-2307, note: Read with SDL_LoadBMP and passed to SDL_COMPAT_WM_SetIcon, which takes a null surface.

**unused:**

- filename: status_bar.bmp, reason: the gimgs table names statusbar.bmp; no code path reads this second file

rom_sidecars:

- **note:** Both sidecars are keyed on the ROM basename from the config, so renaming or relocating a ROM moves them with it.

**symbols:**

    - **pattern:** <rom basename>.sym
    - **source_ref:** machine.c:1129-1133 (load_rom), monitor.c:2676-2691 (mon_new_symbols)
    - **note:** Read for all ten ROMs right after the ROM itself, with verbose off, so an absent file is silent. Fills the debugger symbol tables and nothing else. Compiled out under WWW_NO_MONITOR.

    **shipped:**

    - basic10.sym
    - basic11b.sym
    - pravetzt.sym
    - teleass.sym
    - telmon24.sym
    - microdis.sym
    - jasmin.sym
    - bd500.sym
    - 8dos2.sym

    **referenced_but_not_shipped:**

    - hyperbas.sym

**patches:**

    - **pattern:** <rom basename>.pch
    - **source_ref:** machine.c:1726-1740 (load_patches), machine.c:1933,1970,2007,2033,2083 (call sites)
    - **note:** Read for the machine ROMs only, never for the disk controller ROMs. Carries the keyboard layout, the CLOAD/CSAVE filename decoding addresses, the tape turbo hook addresses and any number of literal by...
    **shipped:**

    - basic10.pch
    - basic11b.pch
    - pravetzt.pch
    - telmon24.pch

    **referenced_but_not_shipped:**

    - teleass.pch
    - hyperbas.pch

**unconfigured_basenames:**

    - **note:** These sidecars ship for ROM basenames no default config names. They take effect only once a config key points at that basename, and each one implies a ROM dump Oricutron can run.

    **files:**

    - filename: Bas122uk.pch, implies: Oric BASIC 1.22 UK, as an atmosrom value
    - filename: Bas122fr.pch, implies: Oric BASIC 1.22 French, as an atmosrom value
    - filename: Bas122de.pch, implies: Oric BASIC 1.22 German, as an atmosrom value
    - filename: pravetzt-1.0.pch, implies: Pravetz BASIC revision 1.0, as a pravetzrom value
    - filename: pravetzt-1.0.sym, implies: Pravetz BASIC revision 1.0, as a pravetzrom value
    - filename: 8dos.sym, implies: the earlier Pravetz 8-DOS boot PROM, offered as pravetz8drom in oricutron.cfg:44
    - filename: cumana.sym, implies: a Cumana controller ROM; its symbols run from $F800, the window jasminrom feeds
    - filename: sedoric.sym, implies: a Sedoric DOS ROM; its symbols name the Microdisc FDC registers at $310-$318

unused_resources:

  • filename: empty_orix.rom, reason: no reference anywhere in the tree; not named by any config default nor by twilighte.cfg
  • filename: orixbank1.rom, reason: no reference anywhere in the tree; loadable only once a twilbankromNN key names it
  • filename: orixbank2.rom, reason: no reference anywhere in the tree; loadable only once a twilbankromNN key names it
  • filename: orixbank3.rom, reason: no reference anywhere in the tree; loadable only once a twilbankromNN key names it
  • filename: orixbank4.rom, reason: no reference anywhere in the tree; loadable only once a twilbankromNN key names it
  • filename: orixbank5.rom, reason: no reference anywhere in the tree; loadable only once a twilbankromNN key names it
  • filename: orixbank6.rom, reason: no reference anywhere in the tree; loadable only once a twilbankromNN key names it
  • filename: orixbank7.rom, reason: no reference anywhere in the tree; loadable only once a twilbankromNN key names it

user_supplied_paths:

- **note:** Named on the command line or in the config, with no fixed filename
**entries:**

- what: disk, tape and snapshot images, source_ref: main.c:1361-1504, oricutron.cfg:63-86
- what: debugger symbol file, -s or --symbols, source_ref: main.c:1533-1545
- what: breakpoint list, -r or --breakpoint with a leading colon, source_ref: main.c:1547-1574
- what: keyboard mapping, autoload_keyboard_mapping, source_ref: main.c:665 (config key), main.c:2188, keyboard.c:587-598, oricutron.cfg:220
- what: CH376 sdcard and usbdrive trees, telestrat mode, source_ref: plugins/ch376/ch376.c:1186, ReadMe.txt:512-514

generated_files:

**written_only:**

- printer_out.txt
- AVI captures
- snapshots
- tape captures
- debugger log and memory dumps

- **note:** Produced by the emulator, none is user-supplied
Technical notes

Oric-1, Oric-1 16K, Oric Atmos, Telestrat and Pravetz 8D emulator by Peter Gordon. Recalbox packages it for its oricatmos system, ES-DE offers it for oric alongside MAME and starts it with the working directory set to the emulator directory.

ROM names are configured without the extension: load_rom appends ".rom" (machine.c:1089-1093). The defaults are set in preinit_gui (gui.c:2283-2297) behind ROMPREFIX, which is "roms/" everywhere except AmigaOS ("PROGDIR:roms/") and the emscripten build ("assets/roms/") (system.h:38-68). A path read from oricutron.cfg goes through read_config_path (main.c:341-347), which prepends the program directory resolved from argv[0] (main.c:196-236), so a relative path resolves against the directory holding the binary rather than the working directory.

The machine ROM is loaded by init_machine for the selected machine type and a failure returns SDL_FALSE, after which the emulator exits (main.c:1442-1446). The four disk controller ROMs are loaded once at startup by load_diskroms (main.c:1407, machine.c:1249-1255) whatever the machine and the drive setting; a failure only clears the matching flag and startup continues. Of those flags only pravetzrom_valid is read afterwards (machine.c:1055): the Microdisc, BD-500 and Jasmin buffers are mapped into the CPU address space whether or not the file was read, so a missing file leaves the selected controller running on zeroed memory.

Size is the only property the code checks. A machine ROM is rejected above 16384 bytes and is loaded right-aligned in its bank, so a shorter file is accepted (machine.c:1101-1118). A disk controller ROM is read as one fixed-length block, which fails when the file is shorter than that length and ignores anything past it (machine.c:1120-1126). No hash is computed anywhere in the tree.

Telestrat banks 0 to 4 hold RAM unless the config names a file for them (machine.c:2029-2038). The Twilighte board is off by default and is switched on with twilighte_board in oricutron.cfg (main.c:660). Its bank config is opened as a bare relative path (oric_twilighte_board_plugin.c:132) and the bank filenames in it are read with read_config_string rather than read_config_path (oric_twilighte_board_plugin.c:174,182), so both resolve against the working directory and not the program directory.

12 files | 6 required, 6 optional | 12 in repo, 0 missing

basic11b.rom required in repo
Oric Atmos BASIC 1.1b ROM

  • Size: max 16.0 KB
  • Validation: size
  • Source: gui.c:2283, main.c:553, machine.c:2006-2007
  • Platforms: recalbox
  • Atmos is the machine oricutron.cfg selects, so this is the ROM a stock configuration needs. Also named by twilbankrom06 in the Twilighte board config (plugins/twilighte_board/twilighte.cfg:3).

basic10.rom required in repo
Oric-1 BASIC 1.0 ROM

pravetzt.rom required in repo
Pravetz 8D BASIC ROM

teleass.rom required in repo
Telestrat TELEASS ROM, bank 5

hyperbas.rom required in repo
Telestrat HYPER BASIC ROM, bank 6

telmon24.rom required in repo
Telestrat TELEMON 2.4 ROM, bank 7

microdis.rom optional in repo
Microdisc disk controller ROM

  • Size: min 8.0 KB
  • Validation: size
  • Source: gui.c:2285, main.c:555, machine.c:1251, machine.c:904-911
  • Platforms: recalbox
  • Conditional: needed for the Microdisc controller, which is the drive type a disk image falls back to when none is given (main.c:1409-1410, 1488-1489). Loaded whatever the machine and not fatal, and setup_for_microdisc raises romdis, so an absent file leaves the $E000 overlay reading zeroes.

bd500.rom optional in repo
ByteDrive BD-500 disk controller ROM

  • Size: min 8.0 KB
  • Validation: size
  • Source: gui.c:2286, main.c:556, machine.c:1252, machine.c:937-944
  • Platforms: recalbox
  • Conditional: needed for the BD-500 controller, selected with -k bd500 or by autodetecting a BD-500 image (main.c:1478-1481). Same non-fatal load and same zeroed overlay as the Microdisc ROM. The rom16 and dos70 config keys change how ROMDIS disables the chips (oricutron.cfg:98-106).

jasmin.rom optional in repo
Jasmin disk controller ROM

  • Size: min 2.0 KB
  • Validation: size
  • Source: gui.c:2287, main.c:557, machine.c:1253, machine.c:836-844
  • Platforms: recalbox
  • Conditional: needed for the Jasmin controller, selected with -k jasmin or by autodetecting a Jasmin image (main.c:1468-1471). setup_for_jasmin leaves romdis clear, so the machine still boots from its BASIC ROM.

8dos2.rom optional in repo
Pravetz 8D floppy controller boot PROM

  • Size: min 512 B
  • Validation: size
  • Source: gui.c:2289, main.c:559, machine.c:1254, machine.c:1053-1058
  • Platforms: recalbox
  • Conditional: needed for the Pravetz 8D drive. The only disk ROM whose load flag is read back, so the Pravetz machine boots without it and only the drive is lost. oricutron.cfg:44-45 gives roms/8dos as the other value for this key, and roms/8dos.sym ships for it.

kernel.rom optional in repo
Orix kernel, Twilighte board ROM bank 7

shell.rom optional in repo
Orix shell, Twilighte board ROM bank 5

Generated on 2026-08-23T16:12:06Z