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1500 questions
49
votes
6 answers
Can a PET 2001 be physically damaged from BASIC?
In the early 1980s my primary school was the proud owner of a Commodore PET 2001.
There was a commonly held belief among the young geek fraternity that there existed a BASIC command—perhaps a POKE—which would cause physical damage to the machine. I…
Flup
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49
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4 answers
Why do older computer cases turn yellow?
Why do plastic cases of old computers turn yellow? Is this yellowing a problem that has been solved in modern plastics?
CommonerG
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49
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2 answers
How did the Z80 instruction set differ from the 8080?
The Zilog Z80 microprocessor, known for its use in the ZX Spectrum, was designed to be a backwards-compatible extension to the Intel 8080 processor. It introduced several new instructions to the 8080's instruction set, as well as adding or extending…
wizzwizz4
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49
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10 answers
Why did 1950s-60s computers have such wide words?
Modern general-purpose computers typically have a 64-bit word size, but looking back in time, we see narrower CPUs. In the early 80s, the 68000 dealt with 32-bit addresses but the ALU was only 16 bits (so a single 32-bit addition took a pair of ALU…
rwallace
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49
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1 answer
What is the context of the button "Is MS DOS a feminist?"
I just saw this button in the Computer History Museum, and I'm wondering what is the context?
Context removed, "Is MS DOS a feminist?" is about the most non-sequitur thing I've seen.
Evan Carroll
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49
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5 answers
How did Atari lose money on home computers?
The answer recently posted to Did Atari make more money from arcade games or consoles? quotes a New York Times article from 1982 https://www.nytimes.com/1982/12/19/business/the-game-turns-serious-at-atari.html
Atari's future may lie with its home…
rwallace
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49
votes
9 answers
Why weren't bootable game disks ever common on the IBM PC?
While for other platforms of that era (primarily, Amiga), putting a game on a bootable disk was quite a normal practice, this approach never taken off on IBM PC. Why not?
I do remember people having multiple menu-driven autoexec.bat and config.sys…
DmytroL
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49
votes
3 answers
Strange math syntax in old basic listing
I'm browsing through an old book "Basic Computer Simulation" from 1983. It contains a line of BASIC code that reads:
LET Z1 = M * D1 * (PQ / A) [ 3
I understand all of the code except the "[ 3" I don't ever remember that syntax in any BASIC I…
Ron Jensen
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48
votes
8 answers
What was the first programming book
I'm curious, what was the first book, about programming for digital computers.
I tried to google it, but it led me to multiple results.
I'm mostly interested in the language it was about and the writer.
Bálint
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48
votes
9 answers
Why did the IBM PC need a sound card?
The original IBM PC and later variants used an Intel 8253 or 8254 as a sound chip. Why did users add sound cards such as the Adlib or Sound Blaster. I remember voice output with programs like telephone answering programs. The sound was wimpy but I…
jwzumwalt
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48
votes
10 answers
What limited the use of the 6809 CPU in personal computers?
Why did manufacturers of home computers avoid using the 6809 CPU? I realize that the Z80 and 6502 had a 3- or 4-year head start in availability. But once it did become available in 1978, I don't understand why designers of new computers didn't…
RichF
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48
votes
4 answers
Why are first four x86 General Purpose Registers named in such unintuitive order?
On x86 the first four general-purpose registers are named AX, CX, DX, BX. It would be quite intuitive if their indices (those used in instruction encoding) were in alphabetical order, but instead of ABCD we actually have ACDB. E.g. mov bl, 1 is…
Ruslan
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48
votes
5 answers
What protocol do Teletypes use?
(By "Teletype" I mean all teletypewriters compatible with the protocol used by the Teletype.)
The Teletype was the dumbest of all dumb terminals, which meant that it was cheap. This means that it was widely spread, and so that computers would be…
wizzwizz4
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48
votes
1 answer
Where and when did the `0x` convention for hexadecimal literals originate?
By the early 1980s, C was using 0x as a prefix to indicate integer literals expressed in hexadecimal, e.g., 0xCAFE. This did not exist in B as of 1972, though B did support octal integer literals via a 0 prefix.
Where and when was this 0x prefix…
cjs
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48
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6 answers
How did musicians acquire samples for tracker music (MOD, S3M, XM and the like)?
Many songs in the so called "tracker" format quite popular in the early 90s (think .MOD, .S3M, .XM, .IT and the like) seemingly used sound samples from real synthesizers. This sometimes could also be seen in the sample names in the tracker music…
DmytroL
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