Skip to content

Clock Signal (CLK)
Type standalone
Source https://github.com/TomHarte/CLK
Version 2026-07-28
Revision TomHarte/CLK@53a1ee78f2f6
Profiled 2026-03-26
Profile YAML, JSON
Cores clk
Systems amstrad-cpc, acorn-archimedes, acorn-electron, acorn-bbc-micro, amiga, apple-ii, apple-iigs, apple-macintosh, atari-2600, atari-st, colecovision, commodore-plus4, commodore-vic20, enterprise-64-128, microsoft-msx, microsoft-msx2, oric, pc-compatible, sega-mastersystem, sinclair-zx80-81, sinclair-zx-spectrum, thomson-mo5, thomson-mo6
Technical notes

Multi-system cycle-accurate emulator by Tom Harte. Used by Batocera and RetroBat as a standalone emulator. Invoked as clksignal with --rompath pointing to the BIOS directory.

ROM resolution: {rompath}/{machine_name}/{filename}. Machine names are fixed strings per system (e.g. "Enterprise", "Oric", "AmstradCPC"). Batocera passes --rompath=/userdata/bios/.

All ROMs are loaded via a centralized ROM::Request/ROMFetcher system. No hash validation at runtime. CRC32s in the ROM catalogue are for host platform identification only. Sizes are enforced via truncation/padding.

Built-in ROMs (compiled into binary, no external file needed): Amstrad CPC (all 7), ZX Spectrum (all 4), ZX80 + ZX81. These systems function without external ROM files. User-supplied files override the built-in copies.

Atari 2600 requires no system ROM (cartridge-only).

118 files | 52 required, 66 optional | 118 in repo, 0 missing

ROM311 required in repo #
RISC OS v3.11

basic.rom required in repo #
Acorn BASIC II ROM, shared by BBC Micro and Electron

os12.rom required in repo #
BBC MOS v1.2

dfs09.rom optional in repo #
Acorn 8271 DFS 0.9 ROM

dfs-2.26.rom optional in repo #
Acorn 1770 DFS 2.26 ROM

adfs-1.30.rom optional in repo #
Acorn ADFS 1.30 ROM

ADT-1.40.rom optional in repo #
Advanced Disc Toolkit 1.40 ROM

TUBE110.rom optional in repo #
6502 Tube 1.10 Boot ROM

Z80_122.rom optional in repo #
Z80 Tube 1.22 Boot ROM

basic.rom required in repo #
Acorn BASIC II ROM (Electron copy)

os.rom required in repo #
Electron MOS ROM v1.00

ADFS-E00_1.rom optional in repo #
E00 ADFS ROM, first slot

ADFS-E00_2.rom optional in repo #
E00 ADFS ROM, second slot

adfs.rom optional in repo #
Acorn ADFS ROM

DFS-1770-2.20.rom optional in repo #
1770 DFS ROM

ELK130E.rom optional in repo #
IDE-modified ADFS 1.03 ROM

AP6v133.rom optional in repo #
Advanced Plus 6 ROM

Kickstart-v1.3-rev34.5-1987-Commodore-A500-A1000-A2000-CDTV.rom required in repo #
A500/A1000/A2000/CDTV Kickstart 1.3 ROM

os464.rom optional in repo #
CPC 464 firmware

basic464.rom optional in repo #
CPC 464 BASIC ROM

os664.rom optional in repo #
CPC 664 firmware

basic664.rom optional in repo #
CPC 664 BASIC ROM

os6128.rom optional in repo #
CPC 6128 firmware

basic6128.rom optional in repo #
CPC 6128 BASIC ROM

amsdos.rom optional in repo #
Amstrad Disk Operating System

apple2o.rom required in repo #
Original Apple II ROM

apple2.rom required in repo #
Apple II+ ROM

apple2eu.rom required in repo #
Apple IIe ROM

apple2e.rom required in repo #
Enhanced Apple IIe ROM

apple2-character.rom required in repo #
Apple II/II+ character ROM

apple2eu-character.rom required in repo #
Apple IIe character ROM

apple2e-character.rom required in repo #
Enhanced Apple IIe character ROM

scsi.rom optional in repo #
Apple II SCSI card ROM

apple2gs.rom required in repo #
Apple IIgs ROM01

apple2gs.rom2 required in repo #
Apple IIgs ROM03

apple2gs.chr required in repo #
Apple IIgs character ROM

341s0632-2 required in repo #
Apple IIgs ROM03 ADB microcontroller ROM

tos100.img required in repo #
UK TOS 1.00 ROM

coleco.rom required in repo #
ColecoVision BIOS

1540.bin optional in repo #
Commodore 1540 floppy drive ROM

1541.bin optional in repo #
Commodore 1541 floppy drive ROM

boot-16.rom optional in repo #
Disk II 16-sector boot ROM

state-machine-16.rom optional in repo #
Disk II 16-sector state machine ROM

  • Path: DiskII/state-machine-16.rom
  • Size: 256 B
  • CRC32: b72a2c70
  • Source: Machines/Utility/ROMCatalogue.cpp:536-543, Components/DiskII/DiskII.cpp:187-239
  • Collection copy: bios/Apple/Apple II/DiskII/state-machine-16.rom
  • Platforms: retrobat disk2-16seq.rom
  • Conditional: needed for disk controller. Also used by Oric Pravetz. The catalogue accepts 9796a238 and b72a2c70, the same PROM in two byte orders. set_state_machine() takes an image whose first byte is 0x18 as already in Beneath Apple ProDOS order (b72a2c70) and only reorders its addresses. Any other image is read as the unadulterated P6 PROM (9796a238), its address lines and the top nibble of each value remapped into that order. Both give the same internal table.

boot-13.rom optional in repo #
Disk II 13-sector boot ROM

state-machine-13.rom optional in repo #
Disk II 13-sector state machine ROM

exos10.bin required in repo #
Enterprise EXOS ROM v1.0

exos20.bin required in repo #
Enterprise EXOS ROM v2.0

exos21.bin required in repo #
Enterprise EXOS ROM v2.1

exos23.bin required in repo #
Enterprise EXOS ROM v2.3

basic10.bin required in repo #
Enterprise BASIC ROM v1.0

BASIC 1.0 - EPROM 1-2 (198x)(Enterprise).bin optional in repo #
Enterprise BASIC ROM v1.0, Part 1

BASIC 1.0 - EPROM 2-2 (198x)(Enterprise).bin optional in repo #
Enterprise BASIC ROM v1.0, Part 2

basic11.bin required in repo #
Enterprise BASIC ROM v1.1

BASIC 1.1 - EPROM 1.1 (198x)(Enterprise).bin optional in repo #
Enterprise BASIC ROM v1.1, with trailing byte

basic21.bin required in repo #
Enterprise BASIC ROM v2.1

epdos.bin optional in repo #
Enterprise EPDOS ROM

exdos.bin optional in repo #
Enterprise EXDOS ROM

mac128k.rom required in repo #
Macintosh 128k ROM

mac512k.rom required in repo #
Macintosh 512k ROM

macplus.rom required in repo #
Macintosh Plus ROM

bios.sms optional in repo north-america, europe, oceania, brazil #
European/US Master System BIOS

japanese-bios.sms optional in repo japan #
Japanese Master System BIOS

msx.rom required in repo #
Generic MSX BIOS

msx-japanese.rom optional in repo #
Japanese MSX BIOS

msx-american.rom optional in repo #
American MSX BIOS

msx-european.rom optional in repo #
European MSX BIOS

disk.rom optional in repo #
MSX-DOS ROM

msx2.rom required in repo #
Generic MSX2 BIOS

msx2ext.rom required in repo #
MSX2 extension ROM

fmpac.rom optional in repo #
MSX-MUSIC / FM-PAC ROM

basic10.rom required in repo #
Oric BASIC 1.0

basic11.rom required in repo #
Oric BASIC 1.1

pravetz.rom required in repo #
Pravetz BASIC

colour.rom optional in repo #
Oric colour ROM (128-byte version)

ORIC.PAL-PROM-TBP24S10-1ab9b572.bin optional in repo #
Oric colour ROM (256-byte version)

PRAVETZ-8D.PAL-PROM-82S129-1576a69b.bin optional in repo #
Pravetz 8D colour ROM

bd500.rom optional in repo #
Oric Byte Drive 500 ROM

jasmin.rom optional in repo #
Oric Jasmin ROM

microdisc.rom optional in repo #
Oric Microdisc ROM

8dos.rom optional in repo #
8DOS boot ROM

GLABIOS_0.2.5_8T.ROM required in repo #
8088 GLaBIOS 0.2.5

GLaTICK_0.8.5_AT.ROM optional in repo #
AT GLaTICK 0.8.5 RTC option ROM

Phoenix 80286 ROM BIOS Version 3.05.bin required in repo #
Phoenix 80286 BIOS 3.05

at-bios.bin required in repo #
IBM PC AT BIOS v3

BIOS_5170_15NOV85_U27_61X9266_27256.BIN optional in repo #
IBM PC AT BIOS, Nov 1985, U27 chip

BIOS_5170_15NOV85_U47_61X9265_27256.BIN optional in repo #
IBM PC AT BIOS, Nov 1985, U47 chip

CGA.F08 required in repo #
IBM CGA font

EUMDA9.F14 required in repo #
IBM MDA font

ibm_6277356_ega_card_u44_27128.bin optional in repo #
IBM EGA BIOS

ibm_vga.bin optional in repo #
IBM VGA BIOS

ibm-basic-1.10.rom optional in repo #
IBM ROM BASIC 1.10

basic.318006-01.bin required in repo #
C16+4 BASIC ROM

kernal.318004-05.bin required in repo #
C16+4 kernel, PAL-G revision 5

kernal.318004-03.bin optional in repo #
C16+4 kernel, PAL-G revision 3

kernal.318004-04.bin optional in repo #
C16+4 kernel, PAL-G revision 4

mo5-v1.0.rom required in repo #
Thomson MO5 ROM, version 1

mo5-v1.1.rom required in repo #
Thomson MO5 ROM, version 1.1

mo6-v1.rom required in repo #
Thomson MO6 ROM, version 1

mo6-v2.rom required in repo #
Thomson MO6 ROM, version 2

mo6-v3.rom required in repo #
Thomson MO6 ROM, version 3

pc128.rom required in repo #
Olivetti Prodest PC128 ROM

cd90-640.rom optional in repo #
Thomson CD90-640 floppy controller ROM

basic.bin required in repo #
VIC-20 BASIC ROM

characters-english.bin required in repo #
English-language VIC-20 character ROM

kernel-pal.bin required in repo #
English-language PAL VIC-20 kernel ROM

kernel-ntsc.bin required in repo #
English-language NTSC VIC-20 kernel ROM

characters-danish.bin optional in repo #
Danish VIC-20 character ROM

kernel-danish.bin optional in repo #
Danish VIC-20 kernel ROM

characters-japanese.bin optional in repo #
Japanese VIC-20 character ROM

kernel-japanese.bin optional in repo #
Japanese VIC-20 kernel ROM

characters-swedish.bin optional in repo #
Swedish VIC-20 character ROM

kernel-swedish.bin optional in repo #
Swedish VIC-20 kernel ROM

48.rom optional in repo #
ZX Spectrum 48K ROM

128.rom optional in repo #
ZX Spectrum 128K ROM

plus2.rom optional in repo #
ZX Spectrum +2 ROM

plus3.rom optional in repo #
ZX Spectrum +2a/+3 ROM

zx80.rom optional in repo #
ZX80 BASIC ROM

zx81.rom optional in repo #
ZX81 BASIC ROM

Generated on 2026-10-20T03:49:41Z