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1500 questions
26
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3 answers
Why are the Intel 8080's rotate instructions called opposite to intuition?
The Intel 8080 has two pairs of instructions for rotating the value of the accumulator -- RLC/RRC and RAL/RAR.
One of them shifts the 8 bits in the accumulator circularly, writing out into the carry flag the value of the bit that moved from one side…
Danya02
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6 answers
Why didn’t the 1980s micros use MC68010?
These are all legendary 16/32-bit machines that were introduced in 1984 or later that are running the 68000:
Apple Macintosh
Atari ST
Commodore Amiga
Sharp X68000
But the 68010 was already available, in every single case: it launched in 1982. Why…
Jacob Krall
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26
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2 answers
Which software was the first to use copy protection?
While researching early magnetic storage around 1980, I've come to ponder if we know of the first piece of software on removable media that employed copy protection?
The Wikipedia article mentions that copy protection schemes became important when…
Micropolis
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26
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2 answers
Strange version of Windows 3.1 marked with a "W" logo
I was digging through my storage and came across this old copy of Windows 3.1. It's a strange looking version though and am wondering if anyone has any info on it.
The copyright page only mentions Microsoft Corporation but it doesn't look like any…
Zenboy
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26
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3 answers
Why might Quake run slowly on a modern PC in DOS, but not in a virtual machine?
I noticed back in the DOS gaming era that DOS games ran slowly in hi-res modes. I was surprised to discover that this could be true on a modern machine.
I booted a 2017 i5 7200u (I think) laptop into FreeDOS and loaded Quake; predictably no sound…
Leon Simpson
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26
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3 answers
When did 5.25″ floppies exceed the capacity of 8″?
When 5.25″ floppies were introduced, in the mid-to-late seventies, they would have had less capacity than the older 8″ because, well, less area on which to store data.
On the other hand, being cheaper and more compact, it didn't take them long to…
rwallace
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26
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13 answers
Was there a technical advantage to such tall PC tower cases?
I saw a tweet today about what it claims is "the tallest PC case" which appears to have been made by SuperMicro:
Further tweets in the thread include pictures of the inside of the case, which has a ton of empty space. It looks like there is enough…
Moshe Katz
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26
votes
7 answers
Why do variable names in BASIC need type suffixes?
The BASIC I'm most familiar with is Atari BASIC since I had an Atari 800 way back when.
The Atari BASIC Source Book includes details about how Atari BASIC maintains variables. There is a Variable Name Table that essentially assigns an index number…
Willis Blackburn
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26
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9 answers
How common was programming in C targeting 8-bit processors in 1983?
How often was C used to program firmware for 8-bit processors in the early 80s?
I'm reverse engineering a firmware binary for a device built around a Hitachi 6303 processor, manufactured in 1983. Even though I'm new to this architecture, it's simple…
ajxs
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26
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7 answers
How did DOS games manage to have multiple background layers?
Seems like VGA only has one background layer, it appears to be a typical bitmap screen like most home computers of the 80s (Amstrad CPC, Commodore 64 etc.) where each pixel's color is stored in a section of memory that can be written to directly.…
puppydrum64
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26
votes
3 answers
Linux 68k Macintosh emulator
I'm currently using the absolutely ancient "Fusion" emulator to emulate a 68k Macintosh (specifically, a Quadra 700), but it only runs under MS-DOS, so I'm using a VirtualBox VM to emulate that. I'd like to eliminate one layer of…
Mark
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26
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3 answers
How and what did it mean to connect to ARPANET from home?
In the iWoz biography, I read:
Now, TV terminals I already knew a little about. […] I'd already built a terminal that could access the ARPANET, the government-owned network of computers that was the predecessor to the Internet. […] Teletype systems…
natevw
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26
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2 answers
How did the "Programmer's Switch" work on early Macintosh Computers?
The early Apple Macintosh computers (original Mac, Mac 512K, Mac Plus) all came with a "Programmer's Switch" installed on the side. I believe this persisted for a long time, with the switch being present on many Macintosh computers for perhaps a…
Brian H
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26
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2 answers
Was "One-Winged Angel" an actual CD track, or generated by the PlayStation's sound chip with a few samples (SFX) added on top?
"One-Winged Angel" is the musical theme for the final boss of Final Fantasy VII for PlayStation, released 1997. I no longer have my copy, sadly.
In spite of consisting of no less than three CDs, the game's soundtrack, either mostly or exclusively…
R S
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26
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3 answers
What was Pong called in Britain?
Pong, the electronic ping-pong game invented by Atari in 1972, was the first really successful video game.
In Britain, 'pong' was also slang for a nasty smell, and I remember reading somewhere, a long time ago, that Atari became aware of this and…
rwallace
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