The Jupiter ACE was built by two ex-Sinclair engineers who helped design the ZX Spectrum — the only home micro to run FORTH! The archive preserving its legacy needs support. Help keep this Sinclair heritage alive! 🕹️ https://www.jupiter-ace.co.uk/

My morning: read the post, then read the linked Wikipedia article (en.wikipedia.org/wiki/Sinclai...), then read the linked Incomplete Spectrum ROM Disassembly (web.archive.org/web/20150901... and finally read the linked Online Gosh Wonderful ROM Assembly File (web.archive.org/web/20150826...).

Sinclair 4K BASIC for the ZX80 https://lobste.rs/s/tukeyq ##historical ##retrocomputing

Happy Pi Day!

Quicksort inventor Tony Hoare reaches the base case at 92

20 GOTO 10 Popular Computing Weekly (1985-12-12), page 14 Full mag --> https://archive.org/stream/popular-computing-weekly-1985-12-12#page/n13

The Sinclair ZX80 Manual has all the right characters but not necessarily in the right order. 🙂 CHR$ 228 is “>” CHR$ 229 is “<“

The accompanying photo is interesting as that Spectrum never shipped. Instead the US got the TS2068 in silver with a cartridge port.

Implementing a clear room Z80 / ZX Spectrum emulator with Claude Code: antirez.com/news/160

Go Johnny Go! Viz magazine started in 1979.

You know what goes well with pancakes? Yes! A MicroBeast kit! feersumbeasts.com

I am out there where nobody can hear me scream.

https://archive.org/stream/NH2021_Popular_Computing_Weekly_Issue870212.pdf#page/n03/mode/2up (2/2)

Steve Vickers interviewed about his time at Sinclair, saving ROM space on the ZX81 and the ZX Spectrum and the new venture the Jupiter Ace. youtube.com/watch?v=kgWj...

It is with great sadness that we share the news of the death of Prideaux Fellow David M. Webb MBE (1983, Mathematics), who passed away yesterday. David was a distinguished Exonian whose legacy will not be forgotten. 🔗 Read the Rector's tribute: https://ow.ly/hhMa50XWF52 #ExeterCollegeOxford

Happy New Year! ✨ Looking back at 2025 — a great year at SC: • 25 new updates of ZXDB • 8 major releases of new website features and fixes • 2,200+ videos re-created from the lost RZXArchive YouTube channel 🚀 2026 - looking forward to service the ZX Spectrum community - and related machines 😘

Intel announced the 8087 floating-point chip in 1980. Now I have a blog post that explains a small part of the microcode in this chip. www.righto.com/2025/12/8087...

Did you know that the first instruction in the ZX Spectrum ROM is DI - Disable Interrupts. Quite a dramatic entrance. The DI instruction was not used in the ZX80 and ZX81. Here is my ZX80 assembly listing from 2002. I tried to use the Logan O’Hara labels when apt. web.archive.org/web/20150501...

How to set your ZX Spectrum to 10:00 am. Make it pause for twenty minutes.

The ZX Spectrum has accurate integers using binary logic. After any decimal point, every digit is converted into an inaccurate recurring binary which is then added to the running total. This is fuzzy logic and all the duds average each other out so that half the time the number is correct. #fuzzy

Wow! The source code for the ZX Spectrum has been posted to the Internet Archive by Timex Computer Corp. see my other posts. Right at the end where the 7 byte “ROOT:” routine is Steven has written “***REPLACE WITH NEWTON-RAPHSON SQUARE ROOT***” I used it in the SG03.rom for the ZX81 and now BL81.

Did you know that the Complete ZX Spectrum source code has been uploaded to Internet Archive by Timex. It was written by Nine Tiles on Zilog Development Studio and Timex obtained the same software. A bit dry but there is a FART joke in there. See the last file. archive.org/details/time...

Website Task Flowchart xkcd.com/3175/

Popular Computing Weekly cover (12/12/1985) READ: https://archive.org/stream/NH2021_Popular_Computing_Weekly_Issue851212.pdf#page/n00/mode/2up #zxspectrum #retrogaming

Speccy clone storms back for Christmas without a shred of Sinclair code

“The Spectrum” an iconic modern version of the 1982 classic ZX Spectrum, is now on sale in the UK for £59.99 at Amazon. A bargain and the default square root is my fast and accurate 2003 routine. Twenty games included but in my experience it runs everything.

Ever wanted to know how your ZX81 ranked against a CRAY supercomputer from 1984? Assuming your eyesight is good enough, now you know.

Here's a Sinclair Microdrive cartridge with a UK pound coin for comparison. We trusted these mini-magnetic tape loops with our valuable data in the 1980s. Totally insane! To be fair, they were actually quite reliable. The tape loop is 5 metres long and stores a minimum of 85 to 100KBytes of data.

One of the most difficult BBC Micro books to obtain. Is there anyone out there that has a copy? I managed to get an ex-library copy that was re-bound. Curious to know how many are actually around. It was withdrawn from sale for legal reasons - it contained an annotated disassembly of BBC BASIC.

This is the most exciting ZX81 BASIC program ever. It runs on any Sinclair ZX81 model - TS1000 etc. It compares the upcoming LG81 ROM with the host ZX81 ROM. This BASIC program should be downloadable soon but if you want to see how bad your ZX81 is get typing. Developed on iOS ZX81 by Kevin Palser.

Download The Looking Glass ZX Spectrum ROM V1.08 from spectrumcomputing.co.uk/entry/44586/... speccy4ever.speccy.org/_CMS.htm ZX Spectrum ROMs and games.

This is the most revealing ZX Spectrum BASIC program ever. It runs on any Sinclair model - Spectrum, TS2068, or any clone. It compares the error-free Looking Glass ROM v1.08 against the host ZX ROM. It should be downloadable by the weekend but if you want to see how bad it your Speccy is get typing.

Remember in the 1980s when Sinclair and Amstrad dropped the price of The ZX Spectrum. Well RGL have continued the tradition and you can buy The Spectrum for £84.99 - 5% off. Just download the Looking Glass ROM V1.08 from Spectrum Computing or speccy4ever www.smythstoys.com/uk/en-gb/gam...

Back in 2014 Dr. Steve Vickers made some lecture slides available on his University website. I used his decimal to binary conversion routines to expand on a floating point display program I had typed in. This created a virtual computer with correct exponent and mantissa to test my ZX Spectrum ROMs.

The very brief mention of MGT's ZX Spectrum Emulator in the #SAMCoupe user guide here, being called "a special program". For the initial emulator MGT had to create a compatible #ZXSpectrum ROM from scratch, as the actual ZX ROM's copyright was held by Amstrad. The compatible ROM wasn't fully...

The Looking Glass ROM V1.08 for the 48K ZX Spectrum is now available for download with documentation. speccy4ever.speccy.org/_CMS.htm This is the most accurate ROM ever available for the ZX Spectrum and is the equal to Microsoft Binary Format 9-digit BASIC. Say goodbye to dodgy figures.

I am no accountant, but this seems very wrong #PostOfficeScandal www.computerweekly.com/news/3666313...

The Fundamental Theorem of Calculus: www.youtube.com/live/L6LPEFt...

What a great day to try some 6502 on your phone! apps.apple.com/app/id154835...

Curious connections: Voyager probes and Sinclair ZX Spectrum

🚀 We’ve just passed 2,000 recreated videos from the RZX Archive! 🎉 Love ZX Spectrum gameplay? Come hang out with us on YouTube 👉 www.youtube.com/@SpectrumCom...

Read all 601 Computer Weekly articles, since 2009, about the Post Office scandal and its aftermath. I keep this guide up to date and links to every article at the bottom www.computerweekly.com/feature/Post...

The ZX Spectrum converts decimal fractions to binary with a well established routine that multiplies each digit by a relevant smaller fraction .1, .01, .001 etc. This achieves maximum accuracy… On the Binary Coded Decimal, Atari 400 and Sinclair calculators !!! What is it doing on the ZX Spectrum ?

I get my first two ZX Spectrum programs published in the letters page of Popular Computing Weekly 1985

Spectrum 48+ Manual READ: https://archive.org/stream/NH2021_spectrumplusmanual.pdf/page/n49/mode/2up #zxspectrum #retrogaming

That iconic scene in Micro Men where the Acorn wire is cut as the BBC enter the building is told for the first time by Hermann Hauser back in 1982! A must-read interview that hasn’t aged.

Website Updates 🚀 - Missing RZX recordings now on YouTube (750+ videos): www.youtube.com/@SpectrumCom... - Collapsible sections on detail page, for easier navigation. - Direct links to preservation tool with prefilled details, such as title and ID. - Quick Search knows your last search type. Enjoy!

Newsgroup comp.sys.sinclair could be informative, even the ZX Spectrum ROM author popped in once. Modern Spectrum designer Chris Smith was sharing his expert knowledge for free thirty years ago from University. Jolly place in its time.

My profile photo is a ZX Spectrum screen I generated from a 1989 program “Other Worlds” that was published on Outlet Microdrive Magazine Issue 026. It was while writing that program I discovered how to tilt the axis of the sphere in any direction.