Messages from an alternative universe where the PDP-10 is alive and well.
Public Key
npub1vdsp5cwwpgwsynch2j6n3ux7dzsfr8q7vph298hvhasn47q0umms6v8zuc Profile Code
nprofile1qqsxxcq6v88q58gzfut4fdfc7r0x3gy3ns0xqm4znmkt7cf6lq87dacpz3mhxue69uhhyetvv9ujuerpd46hxtnfduqs6amnwvaz7tmwdaejumr0ds3jpk4f
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Published at
2026-08-21T07:58:53Z Event JSON
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"created_at": 1787299133 ,
"kind": 0 ,
"tags": [
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"content": "{\"name\":\"Lars Brinkhoff\",\"about\":\"Messages from an alternative universe where the PDP-10 is alive and well.\\nITS research and restoration posted here.\",\"picture\":\"https://mastodon.sdf.org/system/accounts/avatars/000/066/665/original/cf736cf7660c9cd0.jpeg\",\"nip05\":\"[email protected] \",\"fields\":[[\"ITS\",\"https://github.com/PDP-10/its\"],[\"Emacs\",\"https://github.com/larsbrinkhoff/emacs-history\"],[\"Forth\",\"https://github.com/larsbrinkhoff/lbForth/\"]]}" ,
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Last Notes npub1vdsp5cwwpgwsynch2j6n3ux7dzsfr8q7vph298hvhasn47q0umms6v8zuc Lars Brinkhoff @nprofile…kq5d @nprofile…472q You can run MUD from here: https://github.com/PDP-10/MUD1 npub1vdsp5cwwpgwsynch2j6n3ux7dzsfr8q7vph298hvhasn47q0umms6v8zuc Lars Brinkhoff @nprofile…kq5d I think Michael Speciner was also involved in LIFE on the PDP-6. npub1vdsp5cwwpgwsynch2j6n3ux7dzsfr8q7vph298hvhasn47q0umms6v8zuc Lars Brinkhoff @nprofile…m7l3 I cherish my thousand abandoned hobbies, I just don't have time for them all and that's fine. npub1vdsp5cwwpgwsynch2j6n3ux7dzsfr8q7vph298hvhasn47q0umms6v8zuc Lars Brinkhoff @nprofile…p0k0 You did something with your hair since I last saw you in 2019. Slay! npub1vdsp5cwwpgwsynch2j6n3ux7dzsfr8q7vph298hvhasn47q0umms6v8zuc Lars Brinkhoff @nprofile…s0wa @nprofile…kq5d I see you made a hardware modification. In the original installation all boxes were upside down. npub1vdsp5cwwpgwsynch2j6n3ux7dzsfr8q7vph298hvhasn47q0umms6v8zuc Lars Brinkhoff @nprofile…kq5d As seen on YouTube. https://www.youtube.com/watch?v=_13TAKuazhM npub1vdsp5cwwpgwsynch2j6n3ux7dzsfr8q7vph298hvhasn47q0umms6v8zuc Lars Brinkhoff @nprofile…mfuv They went the other way with Commodore 16 and +4. npub1vdsp5cwwpgwsynch2j6n3ux7dzsfr8q7vph298hvhasn47q0umms6v8zuc Lars Brinkhoff IBM may have the best mainframes, but DEC has a month named in its honor. npub1vdsp5cwwpgwsynch2j6n3ux7dzsfr8q7vph298hvhasn47q0umms6v8zuc Lars Brinkhoff The LINC hardware is difficult to work with because it needs two types of GND: +0 and -0. npub1vdsp5cwwpgwsynch2j6n3ux7dzsfr8q7vph298hvhasn47q0umms6v8zuc Lars Brinkhoff @nprofile…f4xf @nprofile…02fp A lot is explained if you view X11 as a wrapper around the VAXstation 100 blitter. npub1vdsp5cwwpgwsynch2j6n3ux7dzsfr8q7vph298hvhasn47q0umms6v8zuc Lars Brinkhoff 0xA0 - aty, npub1vdsp5cwwpgwsynch2j6n3ux7dzsfr8q7vph298hvhasn47q0umms6v8zuc Lars Brinkhoff 0x1A - ateen, npub1vdsp5cwwpgwsynch2j6n3ux7dzsfr8q7vph298hvhasn47q0umms6v8zuc Lars Brinkhoff @nprofile…22q0 Adjust this please. npub1vdsp5cwwpgwsynch2j6n3ux7dzsfr8q7vph298hvhasn47q0umms6v8zuc Lars Brinkhoff @nprofile…22q0 Adjust this please. npub1vdsp5cwwpgwsynch2j6n3ux7dzsfr8q7vph298hvhasn47q0umms6v8zuc Lars Brinkhoff @nprofile…22q0 My son and I laughed at the Star Wars reference at the end. npub1vdsp5cwwpgwsynch2j6n3ux7dzsfr8q7vph298hvhasn47q0umms6v8zuc Lars Brinkhoff @nprofile…22q0 Someone ought to port Space Travel over to use the 340 display. npub1vdsp5cwwpgwsynch2j6n3ux7dzsfr8q7vph298hvhasn47q0umms6v8zuc Lars Brinkhoff @nprofile…22q0 @nprofile…ekkm Yes, please preserve the software. When you do, let's coordinate. Miller posted sources on a web page, which may have been the very last version. I put a copy here: https://github.com/pdp11/fuzzball-operating-system npub1vdsp5cwwpgwsynch2j6n3ux7dzsfr8q7vph298hvhasn47q0umms6v8zuc Lars Brinkhoff @nprofile…22q0 I want to work out the bugs, but how? npub1vdsp5cwwpgwsynch2j6n3ux7dzsfr8q7vph298hvhasn47q0umms6v8zuc Lars Brinkhoff @nprofile…22q0 I was too late to the live stream. : - ( npub1vdsp5cwwpgwsynch2j6n3ux7dzsfr8q7vph298hvhasn47q0umms6v8zuc Lars Brinkhoff @nprofile…22q0 Greenblatt says: spin spin. npub1vdsp5cwwpgwsynch2j6n3ux7dzsfr8q7vph298hvhasn47q0umms6v8zuc Lars Brinkhoff @nprofile…22q0 The files extracted cleanly from the DECtape image with this tool. https://github.com/larsbrinkhoff/pdp10-its-disassembler/blob/master/tendmp.c npub1vdsp5cwwpgwsynch2j6n3ux7dzsfr8q7vph298hvhasn47q0umms6v8zuc Lars Brinkhoff @nprofile…22q0 This is interesting. Is the provenance know? The file names look like TOPS-10, but then, TENEX doesn't have any DECtape format with long names, so it could be that too. I understand CMU was a TOPS-10 site at the time, with Maclisp on site. npub1vdsp5cwwpgwsynch2j6n3ux7dzsfr8q7vph298hvhasn47q0umms6v8zuc Lars Brinkhoff The Freeway Crossing game was written by Michael Irrgang in 1971. He made it for Earl Hunt, who was going to use it to measure reaction times in a psychology study. npub1vdsp5cwwpgwsynch2j6n3ux7dzsfr8q7vph298hvhasn47q0umms6v8zuc Lars Brinkhoff @nprofile…c0cq 256 K words. npub1vdsp5cwwpgwsynch2j6n3ux7dzsfr8q7vph298hvhasn47q0umms6v8zuc Lars Brinkhoff @nprofile…22q0 What's a proper LCGer, David Moon? npub1vdsp5cwwpgwsynch2j6n3ux7dzsfr8q7vph298hvhasn47q0umms6v8zuc Lars Brinkhoff @nprofile…2av8 @nprofile…22q0 Speaking of which, is there any chance SDF/ICM will have some version of WAITS up and runniing in the (possibly distant) future? npub1vdsp5cwwpgwsynch2j6n3ux7dzsfr8q7vph298hvhasn47q0umms6v8zuc Lars Brinkhoff @nprofile…02uj @nprofile…3waz @nprofile…8dg9 Who remembers Archie? npub1vdsp5cwwpgwsynch2j6n3ux7dzsfr8q7vph298hvhasn47q0umms6v8zuc Lars Brinkhoff @nprofile…22q0 What day is that? I would have guessed 7/14. npub1vdsp5cwwpgwsynch2j6n3ux7dzsfr8q7vph298hvhasn47q0umms6v8zuc Lars Brinkhoff @nprofile…7wld How about this from a well-known language training app? npub1vdsp5cwwpgwsynch2j6n3ux7dzsfr8q7vph298hvhasn47q0umms6v8zuc Lars Brinkhoff @nprofile…v96l @nprofile…22q0 npub1vdsp5cwwpgwsynch2j6n3ux7dzsfr8q7vph298hvhasn47q0umms6v8zuc Lars Brinkhoff @nprofile…22q0 Duly noted: 3 6 instead of 36. I think I see why. npub1vdsp5cwwpgwsynch2j6n3ux7dzsfr8q7vph298hvhasn47q0umms6v8zuc Lars Brinkhoff @nprofile…22q0 There you have it. DEC said it's a mainframe. npub1vdsp5cwwpgwsynch2j6n3ux7dzsfr8q7vph298hvhasn47q0umms6v8zuc Lars Brinkhoff @nprofile…22q0 When I visited XKL, Mathom had recently left the building, leaving only a few forlorn TOADs skulking in a corner of the computer room. npub1vdsp5cwwpgwsynch2j6n3ux7dzsfr8q7vph298hvhasn47q0umms6v8zuc Lars Brinkhoff @nprofile…22q0 New ones are being made at LSSM, based on original SUDS drawings. npub1vdsp5cwwpgwsynch2j6n3ux7dzsfr8q7vph298hvhasn47q0umms6v8zuc Lars Brinkhoff @nprofile…22q0 @nprofile…udsf @nprofile…v96l Here are some notes about the KL-UDGE: npub1vdsp5cwwpgwsynch2j6n3ux7dzsfr8q7vph298hvhasn47q0umms6v8zuc Lars Brinkhoff This 1961 proposed standard for punched tape has a lozenge ◊ as the printed representation for an ESCAPE code. Around 10 years later, the Stanford and MIT AI labs adopted this glyph for their extended ASCII character set. npub1vdsp5cwwpgwsynch2j6n3ux7dzsfr8q7vph298hvhasn47q0umms6v8zuc Lars Brinkhoff @nprofile…uauk @nprofile…9n6n Not that special. It looks to me like a warmed over PDP-11. And I say that as a fan that grew up in the 80s programming 68000 assembly language. npub1vdsp5cwwpgwsynch2j6n3ux7dzsfr8q7vph298hvhasn47q0umms6v8zuc Lars Brinkhoff New addition to the Emacs collection: UniPress Emacs V2.20 from 1989. npub1vdsp5cwwpgwsynch2j6n3ux7dzsfr8q7vph298hvhasn47q0umms6v8zuc Lars Brinkhoff @nprofile…8f02 I contacted some of the "micro kids" from the book, but alas the microcode source code they wrote doesn't seem to be around any more. npub1vdsp5cwwpgwsynch2j6n3ux7dzsfr8q7vph298hvhasn47q0umms6v8zuc Lars Brinkhoff @nprofile…ddfm @nprofile…9z2k @nprofile…l9v9 Another aspect embodied by GNU Emacs is the use of Lisp. This goes back to Emacs on the Lisp machine and Multics Emacs. This is in contrast to the original ITS Emacs which used TECO instead. However the Lisp machine is an outgrowth of the same MIT AI lab environment as Emacs, so in some sense is part of the same culture. npub1vdsp5cwwpgwsynch2j6n3ux7dzsfr8q7vph298hvhasn47q0umms6v8zuc Lars Brinkhoff @nprofile…ddfm @nprofile…9z2k I think there are many aspects to "Emacs philosophy" but one of them is "ITS philosophy". This again has many aspects, one example of which is the how Emacs is "unexeced" when built. This seems rather quirky today, but makes perfect sense and is standard procedure on ITS and other PDP-10 systems. npub1vdsp5cwwpgwsynch2j6n3ux7dzsfr8q7vph298hvhasn47q0umms6v8zuc Lars Brinkhoff @nprofile…8f02 @nprofile…ddfm @nprofile…ew2u @nprofile…l9v9 I'm mostly amused by the mental contortions people go through in order to reconcile Emacs with Unix philosophy. npub1vdsp5cwwpgwsynch2j6n3ux7dzsfr8q7vph298hvhasn47q0umms6v8zuc Lars Brinkhoff @nprofile…22q0 LSSM is making fresh ones, based on SUDS drawings. npub1vdsp5cwwpgwsynch2j6n3ux7dzsfr8q7vph298hvhasn47q0umms6v8zuc Lars Brinkhoff Happy birthday PDP-10! #OnThisDay 58 years ago, the PDP-10 was first powered on. Whoopee, it goes! npub1vdsp5cwwpgwsynch2j6n3ux7dzsfr8q7vph298hvhasn47q0umms6v8zuc Lars Brinkhoff @nprofile…l9v9 @nprofile…m2ru Yes, I remember. There was a snippet from an old email by Joy where he write about being inspired by TECO somehow. No, I don't know Joy. npub1vdsp5cwwpgwsynch2j6n3ux7dzsfr8q7vph298hvhasn47q0umms6v8zuc Lars Brinkhoff @nprofile…l9v9 @nprofile…kzuj That could well be. I haven't followed Emacs closely; is compilation to machine code in yet? npub1vdsp5cwwpgwsynch2j6n3ux7dzsfr8q7vph298hvhasn47q0umms6v8zuc Lars Brinkhoff @nprofile…l9v9 @nprofile…kzuj How so? Even Emacs 13 has a Lisp compiler. Or are you referring to one of the other two elisps? npub1vdsp5cwwpgwsynch2j6n3ux7dzsfr8q7vph298hvhasn47q0umms6v8zuc Lars Brinkhoff Feliz Navi! npub1vdsp5cwwpgwsynch2j6n3ux7dzsfr8q7vph298hvhasn47q0umms6v8zuc Lars Brinkhoff @nprofile…7vj8 Just briefly. Thanks! npub1vdsp5cwwpgwsynch2j6n3ux7dzsfr8q7vph298hvhasn47q0umms6v8zuc Lars Brinkhoff I'd like to offer some UUCP resources for the modern world. npub1vdsp5cwwpgwsynch2j6n3ux7dzsfr8q7vph298hvhasn47q0umms6v8zuc Lars Brinkhoff @npub1gf2…mfyc Maybe we should change those room names for the SDF machines. npub1vdsp5cwwpgwsynch2j6n3ux7dzsfr8q7vph298hvhasn47q0umms6v8zuc Lars Brinkhoff I have an 1:3 scale VT100 keyboard attached to my laptop. Should make typing 33% faster. npub1vdsp5cwwpgwsynch2j6n3ux7dzsfr8q7vph298hvhasn47q0umms6v8zuc Lars Brinkhoff @npub1sny…ax7g I think I see Zmacs editing Lisp code. npub1vdsp5cwwpgwsynch2j6n3ux7dzsfr8q7vph298hvhasn47q0umms6v8zuc Lars Brinkhoff I'm sad to learn Gordon Bell passed away on May 17th. npub1vdsp5cwwpgwsynch2j6n3ux7dzsfr8q7vph298hvhasn47q0umms6v8zuc Lars Brinkhoff Music keyboards have long lagged behind the more evolved computer keyboard with regards to user friendliness. But I think I have found a solution. npub1vdsp5cwwpgwsynch2j6n3ux7dzsfr8q7vph298hvhasn47q0umms6v8zuc Lars Brinkhoff Congratulations to all Data General fans for making those great jokes yesterday. npub1vdsp5cwwpgwsynch2j6n3ux7dzsfr8q7vph298hvhasn47q0umms6v8zuc Lars Brinkhoff Can someone translate from Chinese? https://www.youtube.com/watch?v=7zwS1hZSoWU npub1vdsp5cwwpgwsynch2j6n3ux7dzsfr8q7vph298hvhasn47q0umms6v8zuc Lars Brinkhoff The BCC-500 in Hawaii was one of the most obscure ARPANET hosts. Photo by @npub1gsu…wgse npub1vdsp5cwwpgwsynch2j6n3ux7dzsfr8q7vph298hvhasn47q0umms6v8zuc Lars Brinkhoff #OnThisDay 46 years ago, Multics Emacs was started. npub1vdsp5cwwpgwsynch2j6n3ux7dzsfr8q7vph298hvhasn47q0umms6v8zuc Lars Brinkhoff More information and photos: https://github.com/PDP-10/its/issues/1232 npub1vdsp5cwwpgwsynch2j6n3ux7dzsfr8q7vph298hvhasn47q0umms6v8zuc Lars Brinkhoff #OnThisDay 45 years ago, the MIT npub1vdsp5cwwpgwsynch2j6n3ux7dzsfr8q7vph298hvhasn47q0umms6v8zuc Lars Brinkhoff MIT Museum will host a demo of ITS running on the PiDP-10. npub1vdsp5cwwpgwsynch2j6n3ux7dzsfr8q7vph298hvhasn47q0umms6v8zuc Lars Brinkhoff #OnThisDay, 42 years ago, the #MIT AI lab PDP-6 was demolished. Photo: Larry Krakauer. npub1vdsp5cwwpgwsynch2j6n3ux7dzsfr8q7vph298hvhasn47q0umms6v8zuc Lars Brinkhoff @npub13d8…ycpx Geez, those BBS messages are really innocent. Call a public phone number and enter some TIP commands. Not much of a "penetration" of the ARPANET. npub1vdsp5cwwpgwsynch2j6n3ux7dzsfr8q7vph298hvhasn47q0umms6v8zuc Lars Brinkhoff Here's a photo of MIT's XGP printer. There's a PDP-11/20 to the right, which is driving the printer with data sent from the AI lab PDP-10. npub1vdsp5cwwpgwsynch2j6n3ux7dzsfr8q7vph298hvhasn47q0umms6v8zuc Lars Brinkhoff Lisp — putting the "fun" in "funcallable". npub1vdsp5cwwpgwsynch2j6n3ux7dzsfr8q7vph298hvhasn47q0umms6v8zuc Lars Brinkhoff Happy DEC-20! npub1vdsp5cwwpgwsynch2j6n3ux7dzsfr8q7vph298hvhasn47q0umms6v8zuc Lars Brinkhoff Happy DEC-10 day! npub1vdsp5cwwpgwsynch2j6n3ux7dzsfr8q7vph298hvhasn47q0umms6v8zuc Lars Brinkhoff @npub13d8…ycpx npub1vdsp5cwwpgwsynch2j6n3ux7dzsfr8q7vph298hvhasn47q0umms6v8zuc Lars Brinkhoff @npub13d8…ycpx Some other hackers on TV, 1984. https://youtu.be/zOP1LNr70aU npub1vdsp5cwwpgwsynch2j6n3ux7dzsfr8q7vph298hvhasn47q0umms6v8zuc Lars Brinkhoff @npub1r37…xrlz GNU has some history with NE43. npub1vdsp5cwwpgwsynch2j6n3ux7dzsfr8q7vph298hvhasn47q0umms6v8zuc Lars Brinkhoff @npub1gf2…mfyc 36 years is my favorite anniversary!
