Questions tagged [pdp-10]
For questions regarding the DEC PDP-10 computer, also known as DECsystem-10.
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What happened to Doug Engelbart's NLS?
Apparently, it was sold to "Tymshare" in 1977, but what happened to it after that? Who has the software now? Could it ever be emulated?
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What did memory dumps look like on 36-bit machines like PDP-10s?
I spend a lot of time looking at hex dumps of memory, which have a format that should be familiar to most:
00010000 00 FF 48 65 6c 6c 6f 20-77 6f 72 6c 64 21 00 00 ..Hello world!..
But on 36-bit ...
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Why does PDP-6 Fortran need JSA and JRA?
According to pdp10.nocrew.org, the JSA and JRA instructions were invented for PDP-6 Fortran. It's a strange claim; now I don't know anything about Fortran, but I find it hard to convince myself that ...
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Did any 16-bit or 36-bit computer instruction set ever include 4x4 or 6x6 bit-matrix operations?
Donald Knuth's 64-bit MMIX architecture includes several novel instructions that operate matrixwise on an 8x8 square matrix (MOR, MXOR).
(MMIX also has instructions like BDIF that operate vectorwise ...
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Paradigm for (repeated) use of PDP-10 indirect bit
Answers to question PDP-10 effective address calculation explain how PDP-10 effective address calculation works, including potentially infinite indirections.
However the answers don't address how this ...
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Version list for TOPS-10?
So, does anybody have a list of TOPS-10 versions? I haven't been able to find any information aside from versions 7.03, and 7.04. are these lost to time?
To clarify, I'm not asking for the software, ...
user11220
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Why do PDP-10 skip instructions also load an AC?
A recent question on the PDP-10 "JUMP versus JUMPA" prompted this question.
For reference, see this page of instructions.
The SKIP instructions all skip based on the content of a specified memory ...
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When was DEFUN added to Lisp?
I don't see DEFUN in a ~1966 copy of PDP-6 LISP. I do see it in a 1972 Maclisp.
AI memo 116A from 1967 doesn't have DEFUN. (It does have MACRO.)
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How did 36-bit computers format ARPANET packets?
The contract to develop ARPANET, the first version of the Internet, was awarded in 1969; usage of the system expanded exponentially through the seventies.
The size and format of ARPANET packets were ...
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Why was Logo created?
The Logo programming language was created by researchers at MIT's AI Lab. Its post-1980s use has been predominately in the educational field, but is this what the language was originally designed for?
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How was concurrent programming achieved on the PDP-10?
A useful way to do concurrent programming is, say, a Compare-And-Swap instruction, which really is two operations, executed one after the other, atomically. This was available on the IBM 370 and on ...
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What is the difference between CTSS and ITS?
I learned from the history of Multics that in the early days of computers, Time Sharing System (TSS) was used at MIT, and then Compatible Time Sharing System (CTSS) was developed in 1961, also at MIT. ...
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PDP-10 effective address calculation
How does effective address calculation work on the PDP-10?
My understanding is that the instruction code contains an 18-bit address or offset, one bit for indirect, and a register code that's 4 bits. ...
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What are the differences between the various 36-bit computers from DEC?
I want to ask about the
PDP-6
PDP-10
various implementations KA-10, KI-10, KL-10
DECSYSTEM-20
What are the differences between these? I'm not that interested in architectural differences, cache ...
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Is there a non-paging ITS for the PDP-6 or PDP-10?
In the late 60s, the Incompatible Timesharing System ran on a PDP-6 without any paging hardware (i.e. an MMU in modern terminology). See the Jargon entry for BLT, for example, which states (my ...
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What is the FPD bit on the PDP-10?
When an interrupt happens on a PDP-10, as on many other architectures you get the program counter pushed onto the stack. Actually, the program counter includes many status bits in the upper half of ...
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How was the Microsoft PDP-10 8080 emulator developed? [closed]
Altair BASIC, the first version of Microsoft BASIC, was developed using an Intel 8008 emulator, modified to emulate an Intel 8080, running on a PDP-10 computer. This emulator was originally designed ...
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