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1500 questions
24
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8 answers
Why was computer memory so expensive and scarce?
Computer memory used to be a limited and expensive asset for a long while (for example, in computers with 16KiB RAM or less, compared to the 2 MiB of my first PC (an Intel 486) in 1995 and current day's gibibytes).
I guess this was mostly between…
Piovezan
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6 answers
Is there any hard data about type-in programs in the 80s?
In the 1980s, type-in listings were a staple of many home computer magazines[1]. This suggests that they added value to the magazine, and that people did actually type them in. On the other hand, typing in programs was hard, boring work, and while…
Michael Graf
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2 answers
How and why did the ZX Spectrum use so many voltages?
Whilst researching the Zilog Z80, I had found that it accepts a 5V power supply.[2] When looking for information on the ZX Spectrum, I found that its power adaptor produces 9V.[1] Confused, I did some more searching and found that the 4116 DRAM chip…
wizzwizz4
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24
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5 answers
How much benefit should be expected on a more advanced compiler for z80/r800 based computers?
I am self studying about compilers, and get hands on very good textbooks about the subject. I am thinking in develop a compiler using the almighty llvm infrastructure to cross compile to old computers, initially MSX ones.
The thing is, i can't get…
flavio
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votes
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How did early computers handle mice?
Early computer mice worked by sending a series of pulses; the more rapid the movement, the higher the frequency. How was this handled at the computer end?
At one level, it sounds easy: just run a loop, counting pulses. I did find a description of…
rwallace
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24
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11 answers
Why weren't 80s arcade games programmed in C?
I know many arcade games from the 80s were programmed in 68000 assembly. This carried on probably well into the 90s, even though Motorola C compilers existed in the 80s. Why then weren't C compilers used more frequently? Was it an issue with the…
Synthetix
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3 answers
Wiring a Zilog Z80
I've recently got hold of an old Zilog Z80 microprocessor and I know how to clock and test it. I do not however know how to connect RAM, I/O ports, control switches (for programming instructions into ram) or a display for output. I cannot seem to…
DevelopedLogic
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4 answers
How did the Apple II forward binary instructions to the Z80 software card with CPM?
Microsoft produced the Z80 Softcard for the Apple II enabling it to run CPM and many Z80 binary programs.
This seems to be an unthinkable achievement. (For a kid who had an Apple IIe but was only a child at the time).
Can you imagine in the 1990s…
hawkeye
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1 answer
How did the C64 lockup bug and its workarounds work?
The Commodore 64 suffered from a strange bug that caused it to lock up when typing in the full-screen BASIC editor. To trigger the bug, position the cursor on the last line of the screen, type enough text (or even just spaces) to scroll the screen…
Psychonaut
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24
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1 answer
What is the "NES version" of the NES?
This text is displayed on many NES cartridges:
This Game Pak cannot be used with the Mattel or NES versions of the Nintendo Entertainment System
What is "the NES version" of the NES? Is it a very bizarre and unfortunate coincidence that "NES"…
D. R.
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How did Commodore drives produce program listings from disk directories?
CBM BASIC 2.0 has no built-in command for listing the contents of a floppy disk. Instead, the usual way is to LOAD a pseudo-file named $ from the disk into memory. The file can then be LISTed like a normal BASIC program. The listing starts with a…
Psychonaut
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24
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4 answers
What accounted for the cost of ENIAC?
I'm used to the fact that first-generation computers were very expensive, which I had always assumed was because they contained large numbers of vacuum tubes, each of which is a rather complex, high precision little machine in its own right. So it's…
rwallace
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24
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6 answers
Why were pack-in games not usually incorporated on the console mainboard?
In the old days, game consoles were usually sold with a pack-in game, including some iconic titles like 2600 Combat and NES Super Mario Brothers. This makes sense; it provided clear value for the customer, thereby presumably increasing sales.
One…
rwallace
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24
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5 answers
Was Windows 95 really released in 1995?
Here's a recent Microsoft article claiming, "Windows 95 was launched on August 24, 1995".
https://blogs.windows.com/windows-insider/2020/08/24/looking-back-the-25th-anniversary-of-windows-95/
But I distinctly remember thinking that it was late, back…
StayOnTarget
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4 answers
Why is there only one PS/2 port on my computer?
I have an old computer from around 1995. It's from a computer brand that I've never heard of called Samanna Compu-Solutions. I am unsure of the model. The problem is, I only have one PS/2 port to work with. Since the computer is from 1995, there are…
TheComputerMan
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