PDP-10 Emulator in JavaScript

https://github.com/paulnank/nankervis-pdp10-js

by larsbrinkhoff • 5 years ago

44 9 5 years ago

github.com

larsbrinkhoff2• 5 years ago

Sorry, no ITS support (yet).

DonHopkins2• 5 years ago

It just needs a paging box emulator, with a graphical Map-O-Meter!

https://gunkies.org/wiki/Systems_Concepts_DM-10

http://ana-3.lcs.mit.edu/~jnc/tech/pdp10/ITS_Hardware_Memo_2...

http://obsolescenceguaranteed.blogspot.com/2020/02/a-turists...

Writing an emulator for a 36-bit computer in Javascript has special challenges because Javascript provides only 32-bit bit operations. In addition some operands on a KI10 may be up to 71 bits long. As a result bit testing and manipulation must be done with the help of other operators such as division and modulo, and some operands must be split into multiple parts. I hate to think what this does for performance. However if you do encounter performance issues then just upgrade your PC. They are significantly faster and cheaper than a real DECsystem-10, and just imagine the savings in power consumption!

"If you're not playing with 36 bits, you're not playing with a full DEC!" -DIGEX (Doug Humphrey)

sedatk• 5 years ago

It's interesting how similar TOPS-10 is to MS-DOS. I know MS-DOS got the "/" cmdline argument specifier character from CP/M, and CP/M is the one probably based on TOPS-10, but MS-DOS later adopted "EXE" executable extensions, the same extension used for executables in TOPS-10, which weren't a thing in CP/M. So, I guess it wasn't a straightforward generational inheritance, but TOPS-10 influenced MS-DOS directly as well.

WalterBright2• 5 years ago

I was always bemused by the claims that MS-DOS "stole" from CP/M, since CP/M was clearly modeled after the DECSystem-10 and RT-11.

It's too bad Microsoft used EDLIN instead of TECO, however. I miss TECO.

gumby• 5 years ago

Occasionally I absent-mindedly try to press meta-altmode to type a couple of TECO commands, a remnant of when the EMACS command set was not well developed. Amazing that that vestigial muscle memory activates when my brain is really busy on something.

I used to joke about making a TECO machine (custom microcode for the CADR). It would have been way too much work though.

vaxman• 5 years ago

IIRC they were all written on PDP and cross-compiled to Z80/8080 and later the 8086. I heard Billy wrote his BASIC interpreter dialed into a PDP from a motel room in Arizona while living off $100K his famous dad gave him to “get lost” (if the motel was owned by Burt Rutan, that would be too funny.) Later Sun workstations were used to launch Macs, Amigas and AtariST while a traitor was leaving DEC/PDP/VAX to setup shop at MS and create NT which destroyed the tech economy until it was rebuilt by a child who found Andy Tanenbaum’s book and some free sourcecode from a communist at MIT. The free tech allowed the dot com bubble and when that blew and the elders were generally forced into retirement, Amazon saw an opportunity to do the heavy lifting for the poor-wage children left behind, leaving the retired elders to make JavaScript based PDP emulators. It should all be unfsck’d by 2026 tho (that’s when the first wave of formally trained Computer Scientists after the nuclear winter ended will hit 20 years and, with their grey beards and pear shapes, be mentoring several generations behind them…same as it ever was.)

WalterBright2• 5 years ago

Yes, but can it run Empire for the -10?

https://github.com/DigitalMars/Empire-for-PDP-10

larsbrinkhoff2• 5 years ago

Is there a reason it couldn't?

PDP-10 Emulator in JavaScript

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