Microsoft Releases Historic 6502 Basic
52 comments
·September 3, 2025breadwinner
I don't see any credit being given to Digital Equipment Corporation (DEC) upon whose work this is based [1] [2] [3].
The quotes below only talk about OS source code, but they found language interpreter source code as well, see register story.
> "So, for a few years that is where I spent my time. I'd skip out on athletics and go down to this computer center. We were moving ahead very rapidly: BASIC, FORTRAN, LISP, PDP-10 machine language, digging out the operating system listings from the trash and studying those. Really not just banging away to find bugs like monkeys[laughs], but actually studying the code to see what was wrong." [4]
> "While his parents were concerned with his slipping grades, there was no slowing him down. He and Bill would go “dumpster diving” in C-Cubed’s garbage to find discarded printouts with source code for the machine’s operating system"
[1] https://en.wikipedia.org/wiki/BASIC-PLUS#Comparison_to_MS_BA...
[2] https://everybasic.info/doku.php/basics/decbasic#influence_f...
[4] https://americanhistory.si.edu/comphist/gates.htm
[3] https://www.theregister.com/2000/06/29/bill_gates_roots/
phkahler
In that Basic 80 link (number 2) I would have expected another variant to be listed: Microsoft Basic for the Interact Home Computer which used an 8080 processor. BTW I still have my Interact in its box and the MS Basic on tape and some other stuff. Looking for a museum or appropriate place to send it.
wvenable
I saw an ebay listing for one of these Interact computers today and spent a little time learning about it on YouTube. It's so strange to see your post on the same day about a computer I didn't know existed yesterday.
reaperducer
digging out the operating system listings from the trash and studying those.
A lot of us did the same thing in that era. It's surprising how much information can be learned from what others think is useless.
Thank you SUNY New Paltz and the IBM submarine facility (no idea what it was called) for not securing your Dumpsters. It's how I learned computing before it was taught in schools.
DonHopkins
https://news.ycombinator.com/item?id=17998940
DonHopkins on Sept 16, 2018 | parent | prev | next [–]
Speaking of weird BASIC features, does anyone know why DECSYSTEM 20's BASIC had a "LISTREVERSE" command?
Yes, it actually did exactly what it sounds like!
Chalk one up for DEC and BASIC. What other programming languages support that feature, huh?
DECSYSTEM 20 BASIC User's Guide: LISTREVERSE command
LISTREVERSE
LISTNHREVERSE
LISTREVERSE and LISTNHREVERSE print the contents of the
user's memory area in order of descending line numbers.
LISTREVERSE precedes the output with a heading,
LISTNHREVERSE eliminates the heading.
LISTREVERSE
EQUIV 10:53 13-NOV-75
40 END
35 PRINT "THE EQUIVALENT CURRENT IS",I, " AMPERES"
25 I=E1/R
10 INPUT R
5 INPUT E1
READY
dboreham
> upon whose work this is based
Erum, none of your references show this (or come remotely close).
MS did base NT on DEC work, and settled a court case as a result. Perhaps you're thinking of that story?
BASIC the language pre-dates the DEC implementation (it came from Dartmouth College), and nobody would reasonably think that seeing the code for a high level language BASIC interpreter implementation for Machine A, then writing an assembler implementation for Machine B means you "based it on their work".
monocasa
MS BASIC is widely considered to have been based on the internal structure of DEC BASIC.
leoc
Right, though there's two or three different questions here: whether DEC BASIC influenced MS BASIC, whether MS should have acknowledged that today, and whether DEC BASIC's influence on MS BASIC amounted to a copyright violation. On the last question, my guess would be that there's at least a reasonable argument that MS' use of the DEC BASIC code was transformative enough to get them off the hook, but IANAL.
pico303
I love how the initial commit is "48 years ago."
JdeBP
If you enjoyed the datestamps on that repository, you will definitely enjoy the datestamps on this one:
* https://github.com/dspinellis/unix-history-repo
You'll also enjoy the contributors list.
msgilligan
Although that date should really only apply to the `m6502.asm` file. I think for a historical archive accuracy should be important. For example when was it licensed under the MIT license, I assume fairly recently. The file date should reflect that.
commandlinefan
I noticed that right away, too - I didn't know you could force backdates of git history like that.
mananaysiempre
The GIT_AUTHOR_DATE and GIT_COMMITTER_DATE environment variables[1] are what you use for things like that. (The former can also be overridden by the --date= option to git commit, and there’s also various situational stuff like --reset-author for git commit or --committer-date-is-author-date and --reset-author-date for git rebase.)
Tor3
I have source I wrote using SCCS as version control, which later was moved to CVS, preserving the commits as well as commit dates, and at some point moved to Git, again preserving commits and dates. So some of my personal Git repositories have commit entries going back to the late eighties.
For any ordinary commit you can simply include "--date=" with the 'git commit' command, e.g. -m "This is an old change" --date="2001-03-02 18:05:47"
meesles
All git data can be modified
xattt
Are GitHub commit timestamps stored as Unix epoch time? If so, could we get similar timestamp accuracy when working with historical source code from systems like UNIVAC?
prerok
Yes, somebody could doctor those commits with the right timestamp so that we would get a clear historical progression.
It's doable, but would have to doctored, there was no git then, obviously.
badc0ffee
Even if it was a 32-bit timestamp, you could still express dates back to December 13, 1901.
achrono
I love even more how it's a .md file from well before Markdown even existed.
perching_aix
I bet it being a Git repo must straight up feel otherwordly then.
It's just a nice touch.
prerok
No, skynet went to the past and gave git and md to microsoft, which then proceeded to create the doc format from the md as a starting point :P
shanselman
Thanks!
codingwagie
Love the comments:
"7/27/78 FIXED BUG WHERE FOR VARIABLE AT BYTE FF MATCHED RETURN SEARCHING FOR GOSUB ENTRY ON STACK IN FNDFOR CALL BY CHANGING STA FORPNT TO STA FORPNT+1. THIS IS A SERIOUS BUG IN ALL VERSIONS."
Not far off from a comment I might make these days
https://github.com/microsoft/BASIC-M6502/blob/main/m6502.asm...
giancarlostoro
I'm trying for Visual Basic 6 to show up on GitHub someday.
SSLy
that Readme smells of LLMs and elderberries
cube00
QuillBot reports 100% AI for section "Why This Document is Historically Important"
lloydatkinson
> It democratized programming
Yawn. Everything “democratizes” everything these days.
petcat
I think it commercialized programming. True democratization didn't really happen until Stallman, GCC, and the GPL.
dmbche
How about when they invented BASIC
null
oompydoompy74
Who cares?
cyberax
I think, it's the first time I saw "48 years ago" in the most recent change column on Github.
drittich
I cut my teeth on that language, and still keep a Commodore PET around for old times sake.
eggy
I had my Commodore PET for 10 years from 1977 to 1987 until I went away and my cousin borrowed it, and then believing I was not coming back to the US from Spain, sold it!
I loved the cassette drive and all-in-one chassis. Ah, typing in programs from magazines and creating programs from scratch with PET graphics on the keys! I miss those days. So much wonder and fun.
LeoPanthera
That readme is obviously AI generated. I’m happy for anything this historical being open sourced, but I now wonder what the AI has done to the code itself. What a shame.
NitpickLawyer
Well, we can be pretty sure it didn't touch comments :)
> 12/1/77 FIXED PROBLEM WHERE PROBLEM WITH VARTXT=LINNUM=BUF-2 CAUSING BUF-1 COMMA TO DISAPPEAR
pjmlp
They now have OKRs to use AI everywhere, even .NET tooling is getting AI tainted.
ocdtrekkie
I assume AI only generated the readme file. But I would say if AI boilerplate eases Microsoft releasing more of their old code to the public, I am okay with that.
Microsoft recently closed a 7 year old .NET documentation bug I opened using Copilot. I am not a fan of AI but the submitted fix was far superior to the basically useless message that had been previously present, so net positive. At being ignored for 7 years, it was unlikely to get better from human effort.
LeoPanthera
I wouldn't assume that at all. If they're using AI for something as trivial as a readme, I think it is a very safe assumption that that's not all they're using it for.
I wish code repos had a "contaminated by AI" flag.
DonHopkins
Why do you have any reason to believe AI generated any of the 6502 code? What possible reason or motivation could there be for that? Wouldn't it spoil the entire reason for releasing it, totally miss the point of releasing original historic code? Who might possibly benefit by doing that? Are you just making up baseless conspiracy theories or do you have any factual basis for that accusation?
Seems hypocritical for a human being to hallucinate a conspiracy theory about LLMs, with no evidence whatsoever.
lysace
That recent "purchase of Commodore" by some youtuber... it doesn't really include the distribution rights of the C64 ROM containing (a newer version of) this 6502 Basic, right?
I really appreciate that they bothered to set an artificial timestamp for these git commits, roughly 30 years before Git itself existed. The thing is, the other files do, too, and the .gitignore is full of hilariously anachronistic references.