The Incomplete Spectrum ROM Assembly

(and other Sinclair ROMs)


These files were originally generated programatically from the original ROM contents of Sinclair computers and peripherals. Comments and hyperlinks were later manually added to form a simple on-line reference.

Some customized variants of these ROMs are also included.

Plain-text versions can be used as source files for Zilog Z80 cross-assemblers to generate binary images of the ROMs, for instance for use in emulators.

These files were originally hosted at and maintained by Geoff Wearmouth. Unfortunately that website went off-line sometime around the end of 2015 and as of 2017 no copies were available for the casual reader. To keep this valuable historical resource available, some files from that website have been preserved here. Files hosted on this website are from a snapshot captured on 1 September 2015. They were not modified, except for this index page, which was copy-edited for readability.

For any questions regarding this host, please contact Tomaž Šolc. For authors and acknowledgements please see individual files.

ZX Spectrum ROM

The Incomplete Spectrum ROM Assembly.

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The "Gosh Wonderful BASIC" ROM. An adaptation of the standard Sinclair ZX Spectrum ROM. This is a minor rework of the ROM which corrects most of the imperfections discovered during the Beta test phase. The remaining space is used to provide Renumber, Block Delete and Stream Lister commands. More info.

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A complete assembly listing of the ROM of the Sinclair ZX81 / Timex TS-1000.

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The "Shoulders of Giants" ROM. A customized ROM variant made by Geoff Wearmouth. It uses space-saving techniques to make way for Newton's square root calculation, improved decimal number input and consistent output to the screen and printer of floating point numbers.

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A complete assembly listing of the legendary Integer Basic Sinclair ZX80 ROM. Perhaps the most influential computer program ever written.

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Jupiter Cantab Ace ROM

A rudimentry assembly listing of the FORTH-based Jupiter Cantab Ace ROM. By the author of the ZX Spectrum BASIC ROM.

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The ZX Interface 1 ROM Assembly

Two assembly listings of the Shadow ROM that gave Spectrum Users access to real printers, fast storage devices and a Local Area Network.

Version 1

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Version 2 - after serial number 87315

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Last updated: Mon, 29 May 2017 19:21:31 +0200