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1500 questions
18
votes
7 answers
Cost of unrestricted sprites
All the game consoles of the second through fourth generations, and several early home computers, had sprites, which were valuable though costly, e.g. the VIC-II spent 2/3 to 3/4 of its area on sprites, and the Atari 800, which shipped three years…
rwallace
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18
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2 answers
How does one bypass the region lock on Japanese Super Famicom?
I recently bought a Super Famicom on my trip to Japan. However, the console is region locked so you can't play American SNES games. It seems to be that the plastic cartridge doesn't fit in the console housing, so I am assuming it's just a hardware…
wcarhart
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18
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1 answer
Why are the out-of-bounds areas of Doom distorted on MS-DOS?
Why do the OOB (out-of-bounds) areas of Doom look so unusual?
As seen in the image above, the Doom engine not only incorrectly renders the scene, but also renders slices of other scenes that aren't even loaded in the map. This is not the case in…
Badasahog
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18
votes
7 answers
What should be the waveform for ZX Spectrum tapes?
I am digitizing about 40 tapes with programs for the ZX Spectrum.
I am somewhat puzzled by the waveform after digitization.
The signal of most cassettes is meander-shaped.
One of the cassettes can be downloaded from DropBox.
Some cassettes have…
A. Rumlin
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18
votes
1 answer
What was the first operating system that supported preemptive multitasking?
What was the first operating system that supported preemptive multitasking?
By preemptive multitasking I mean that user processes were able to run in a time-sliced manner without special programming, not as loaded interrupt services, etc.
I've heard…
Mark Harrison
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18
votes
6 answers
How slow was the 6502 BASIC compared to Assembly
Imagine a modern computer, where let's say Python is a high level programming language and needs to be interpreted in order to execute a piece of code. You could write some code in C, compile it, which will be much closer to the actual hardware and…
Bartek Malysz
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18
votes
5 answers
What was the first multiprocessor x86 motherboard?
I know dual socket motherboards were around in the 90's before Intel released the Core series. And SMP hardware and operating systems have been around earlier than the PC platform of course.
Multiprocessor support on the IBM PC-based platform, as…
LawrenceC
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18
votes
3 answers
Did any micros use the 6502 BCD mode in their OS?
I know the Atari's FP package used BCD for rather dubious reasons, but does anyone know of other examples of basic "operating system" level code on common platforms that used BCD?
I suspect BCD was added due to the history of using micros in…
Maury Markowitz
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18
votes
1 answer
How did the Game Boy Advance stretch Game Boy games to widescreen?
The original gameboy, GBP and GBC all had screen resolutions of 160x144[1] while the Game Boy Advanced had a resolution of 240x160[2]
So how does the actual stretching occur? It seems pretty uniform, but I can't wrap my head around how it's…
Christopher Wirt
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18
votes
2 answers
Did any early RISC OS precursor run on the BBC Micro?
Acorn famously developed the ARM microprocessor using their existing BBC Micros internally, both to simulate the ARM and to develop for actual ARM using a Tube-connected second processor.
Later, Acorn would ship the ARM-based Archimedes platform,…
Brian H
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17
votes
4 answers
Why are PDP-7-style microprogrammed instructions out of vogue?
DEC, and at least some of their computers, especially those in the 18-bit family and 12-bit family, had these opr instructions, which contained many bitfields which encoded something like "subinstructions". Things like
clear the…
Omar and Lorraine
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17
votes
4 answers
Why did 3.5" floppies win (and not another size)?
It's an open question whether desktops would've kept using 5.25" until the end of the floppy era, but laptops meant something smaller was going to be introduced; that much was essentially predetermined. The contingent historical fact was the…
rwallace
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17
votes
1 answer
I've taken my Amiga computer out of storage after several years and it doesn't work. What's the likely cause?
I've had an Amiga on a shelf for a long time. Today I took it down and tried to use it but it's not working. There's some basic activity - the power LED illuminates, and there is a video signal - but the screen remains dark and the drives…
Richard Downer
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17
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1 answer
How does Apple ][gs hardware dithering work?
I haven't been able to find an easily comprehensible description of the super hi-res, dithered 16-color, 640x200 mode of the Apple ][gs.
I can tell from the references I did locate, this is a hardware supported mode of the VGC. So, the dithering…
Brian H
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17
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3 answers
Where was the DOS cdd utility from?
I distinctly remember, on the computer I had in the 90's, being able to type cdd D:\bla\bla in the MS-DOS command prompt, to change both the current directory and drive (avoiding having to type D: then cd \bla\bla).
I regularly still type it in the…
dim
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