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1500 questions
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1 answer
Is the MANIAC in the movie 'The Magnetic Monster' the real MANIAC computer?
I just watched the movie The Magnetic Monster, which is a 1953 science-fiction thriller. The main premise is hokum, but there's an amount of reasonable-seeming background "science" around.
The heroes, from the Office of Scientific Investigation…
dave
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3 answers
How does this 8080 code perform division with remainder?
Empirically, I've found that this routine (i8080) divides value from E by B and returns the result in D and E (result and remainder of division).
divide_by_12_with_rest:
MVI C, 9 ; @1
MOV A, D ; @2
loop_1:
MOV D, A ; @3
MOV A, E
RAL
…
DraganS
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20
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How can I set up the Microsoft C compiler to make it prefer immediate-mode push instructions?
I started a project to get a better understanding on how to compile a game for Windows 3.x. I tried to set up the build workflow so that it produce the byte-exact clone of a great open sourced Win16 game named Hyperoid. It took some time to get a…
SZIEBERTH Ádám
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1 answer
What size screws were used in the Amiga desktop cases?
On the Amiga 500, 500+, 600, and 1200, what size screws were used to hold the chassis together? Is it the same size screw for all, different screws per machine, different screws front and rear, or were all the holes designed to work with more than…
snips-n-snails
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1 answer
Why is MS-DOS not able to read partitions starting at logical sector 0?
When creating a FAT file system, mtools and newer versions of mkfs.fat write a stub MBR partition table to the boot sector. This makes the file system accessible when written directly to media that some operating systems (i.e. Windows) expect to be…
user3840170
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20
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1 answer
What's the deal with Commodore's RESTORE key?
Most early microcomputers provided either a dedicated key (e.g. Apple ][), keyboard combination (e.g. PC clones), or dedicated hardware button (countless examples) to "Reset" the computer. This was the preferred way to perform a warm restart, which…
Brian H
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20
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3 answers
What is the name of the publishing software used at IBM in the late 80s?
I was a tech writer at IBM in Austin, TX in the late 80s. We were writing documentation for the RS/6000. I loved the publishing software we used and was sorry to see it replaced in the marketplace by cheaper, less powerful software geared towards…
april26
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2 answers
Did any notable product use Intel's first RAM?
The 3101 SRAM was Intel's first product. At $99.50 for 64 bits, it had enough memory to store the characters expensiv. (Sorry, the final e costs extra.) Is there a record of any product using it?
DrSheldon
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Actual code written by Ada Lovelace?
I have seen some claims that Ada Lovelace was the first programmer.
Is there any actual code to back this up?
Tyler Durden
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How did the Apple IIGS automatically slow 5.25 inch disk I/O code for backwards compatability?
Apple II software often used hard-coded timing for 5.25 inch floppy disk I/O, for example to control the duration of each track step or the rate at which bytes are written and read from the disk. Since the Apple IIGS had a faster 2.8 MHz CPU than…
bmow
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20
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2 answers
Why didn't SNES Doom use mode 7?
Doom was ported to the Super Nintendo using a Super FX 2 chip on the cartridge. It has most of the features of the full game, though with a few omissions, such as absence of sound propagation, probably due to the SNES having a much weaker CPU than a…
rwallace
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20
votes
1 answer
What is the function of this strange IBM apparatus?
Does anyone know what kind of device this is? I found it in my late dad's stuff, probably from the 1970s.
It has no number, type, model, serial number or anything else on it that could be used for identification, besides the IBM logo.
Picture…
Congo B. Bongo
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votes
1 answer
Why does Ms. Pac-man turn upside down?
Ms. Pac-man is a game where you navigate a small yellow circle around a maze, collecting dots and fruit whilst avoiding brightly-coloured monsters, or ghosts. This time, however, the yellow dot has an eye, a red bow, some lipstick and a "beauty…
wizzwizz4
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2 answers
Did the 68000 separate A/D registers save circuitry?
The Motorola 68000 has sixteen integer registers, which was considered a very generous complement at the time it was introduced. They are divided into address and data registers, eight each. Many instructions work the same with both kinds, but there…
rwallace
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20
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2 answers
What was the earliest non-valve, non-mechanical computer?
Just wondering how history questions will fare here. They could be a good addition to our scope.
Pretty much exactly as the title says. Some of the earliest computers were based on valve systems or mechanical arrangements. What was he earliest…
Åna
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