Hot answers tagged

33 votes
Accepted

Was 36-bits needed for LISP?

Is there any particular reason you can't do LISP in 18-bits? No, as already commented, LISP can of course be done with any machine word size. It's just that a 36 bit word could hold all elements of a ...
Raffzahn's user avatar
  • 219k
15 votes
Accepted

What are the differences between the various 36-bit computers from DEC?

What are the differences between these? I'm not that interested in architectural differences, cache sizes, etc. I'm most interested in the differences that could feasibly trip up an assembly language ...
Raffzahn's user avatar
  • 219k
11 votes
Accepted

When was DEFUN added to Lisp?

From the MIT AI Lab file .INFO.; LISP ARCHIV for Maclisp updates: 3/1/69 JONL THE CURRENT VERSION OF LISP, "LISP 102", HAS THE FOLLOWING AS-YET UNDOCUMENTED FEATURES: 1)"DEFUN" IS AN FSUBR ...
Lars Brinkhoff's user avatar
10 votes

Was 36-bits needed for LISP?

There have been many implementations of Lisp for machines with registers narrower than 36 bits (most commonly, for 32-bit machines). It’s a high-level language that can be implemented in many ...
Davislor's user avatar
  • 8,667
8 votes

Is there a non-paging ITS for the PDP-6 or PDP-10?

This is a frame from MIT AI film #43. I'm not sure what year it's from, but it seems to be from the PDP-6 era. The code is very similar to old ITS source code, so it's likely this is a tiny fragment ...
Lars Brinkhoff's user avatar
7 votes

Why does PDP-6 Fortran need JSA and JRA?

I think you need to keep the context in mind to understand the decision. The PDP-6 was introduced in 1964. At the time, the number of high level languages in wide use could be counted on one hand with ...
Jerry Coffin's user avatar
  • 4,752
6 votes

What are the differences between the various 36-bit computers from DEC?

This is only a partial answer, and I hesitate to post it because it's going to primarily be a link, but... There are some real, programmer-visible differences between the PDP-6 and the KA10, though ...
patbarron's user avatar
  • 161
6 votes
Accepted

Why does PDP-6 Fortran need JSA and JRA?

It's not that FORTRAN required those particular instructions, but that they were the sort of instructions that existing FORTRANs tended to use. At the time, calling conventions were somewhat unsettled,...
dave's user avatar
  • 35.2k
6 votes

Where can I find software for the PDP-6?

Bitsavers has some PDFs of printouts of tsExec1.4. Not sure if this is complete. There's a lot of PDP-10 software e.g. at trailing-edge, I suppose at least some of that could be adapted to run on the ...
dirkt's user avatar
  • 27k
5 votes

Where can I find software for the PDP-6?

Old versions of the Monitor: http://pdp-6.trailing-edge.com/ PDP-6 notes from ITS, includes some PDP-6 programs: https://github.com/PDP-10/its/issues/278
Lars Brinkhoff's user avatar
5 votes

Where can I find software for the PDP-6?

Update. There is now quite a bit of PDP-6 software, but almost all of it from MIT: Monitor from DEC. SYSTEM GEN, low level DECtape formatting. MACDMP, file system on DECtapes. DDT, debugger. TECO, ...
Lars Brinkhoff's user avatar
4 votes
Accepted

Is there a non-paging ITS for the PDP-6 or PDP-10?

Here's another clue. It seems Gerald Sussman has a printout of ITS from 1967. The[n] he pulled out a printout that he handled as if it were an original Gutenberg bible. It was the original code for ...
Lars Brinkhoff's user avatar
4 votes

Is there a non-paging ITS for the PDP-6 or PDP-10?

Another piece of tantalizing evidence has surfaced. It's an old ITS file called RG; FD 4/1/68. The name obviously suggests a dating, and it's before a pager was installed. The file contents are ...
Lars Brinkhoff's user avatar
4 votes

Where can I find software for the PDP-6?

A significant chunk of PDP-6 software has surfaced: JOSS. https://www.rand.org/pubs/research_memoranda/RM5437.html It's being typed in: https://github.com/PDP-6/JOSS-II
Lars Brinkhoff's user avatar
4 votes

Where can I find software for the PDP-6?

The program was MAC HACK VI. This link doesn't give access to the program, but it may give you some leads about where to find it. It was a chess playing program, and a good one for its time frame. ...
Walter Mitty's user avatar
  • 6,128
4 votes

What are the differences between the various 36-bit computers from DEC?

For the assembly language programmer, perhaps a KS10 acted like a KL-10 Model B (except for I/O, as mentioned), but FWIW the KS10 was a completely new CPU implementation using 10 of the AMD 2901 bit ...
Aron Insinga's user avatar
3 votes

When was DEFUN added to Lisp?

The defun macro is just syntactic sugar for define plus lambda. InterLisp (1970) doesn't seem to have it either, so your MacLisp example is either the first, or pretty close to being the first.
Omar and Lorraine's user avatar
2 votes

What are the differences between the various 36-bit computers from DEC?

For a long while there circulated rumors there used to be a 36-bit computer called the PDP-3. According to legend, DEC made a paper design but never built it themselves. Supposedly one customer took ...
Lars Brinkhoff's user avatar
1 vote

Why does PDP-6 Fortran need JSA and JRA?

(Just a Remark about the being 'modern' or not) It's quite a strange subroutine calling mechanism, as well. The PC is not stored on the stack, like most modern subroutine calling conventions, nor is ...
Raffzahn's user avatar
  • 219k

Only top scored, non community-wiki answers of a minimum length are eligible