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1500 questions
18
votes
4 answers
MSX Assembly/Basic programming documentation
I'd like to try to create software (and maybe simple games) for the MSX standard.
I know I have two ways to do so, either I use MSX Basic or Z80 assembly. I think that Z80 assembly is more powerful than MSX Basic.
I already have experience with…
Informancien
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18
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9 answers
How were bugs reported for compilers that were shipped on floppy disks?
Take the Microsoft C 1.0 compiler for example. It shipped on multiple 5.25" 360K disks, and when it ran on machines without internal hard disk, so users had to switch floppies between the editor, compiler, and linker.
If there was a bug with the…
JAL
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18
votes
1 answer
Did the Macintosh Classic series use DMA to display video?
I'm learning more and more on how the original Macintosh series worked. I can't, however, find information in my research on how the Mac's video generator accessed the video RAM.
My assumption is that it used some sort of DMA transfer in…
cbmeeks
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18
votes
4 answers
How was the main mechanic of the game Qix implemented?
Qix was a quite unique Taito arcade video game that saw ports to nearly any home computing platform of its time. At first glance, the game mechanics seem to be targeted at low-performance hardware - no need for fast pixel graphics, as the game…
tofro
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18
votes
3 answers
Are the 6809 and 6809E different from a programmer's point of view?
I can see the pinouts of these two chips are utterly different. Apparently the 'E needs an external clock as well. This question isn't so much about any of those hardware related differences. This question is about what a programmer can see.
I have…
Omar and Lorraine
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18
votes
1 answer
Why can you not move on the last level on Dig Dug?
The objective of Dig Dug is to eliminate underground monsters by inflating them until they pop, or by squashing them with large rocks. Once all of the monsters have escaped or been defeated, the level progresses.
Once the level number reaches 256,…
wizzwizz4
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18
votes
2 answers
What is the instruction set of the PDP-7?
The PDP-7 was a bookshelf-sized "minicomputer", with keyboard, magnetic and paper tape and printer I/O. According to Wikipedia, the first version of UNIX (then named Unics) was programmed in assembly on the PDP-7.
Despite this, I can't find much…
wizzwizz4
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18
votes
5 answers
Did any computers use automatically-operated mechanical storage as electronically-read-addressable memory
From what I understand of ENIAC, it had a very large number of manually-operated rotary switches which behaved as ROM. While programming ENIAC in the early days required a plugboard, the machine was eventually enhanced to allow it to be programmed…
supercat
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18
votes
2 answers
What is the oldest reference to PEEK, POKE, and USR?
I've been reading manuals for BASIC implementations and the earliest reference I can find to PEEK, POKE, and USR is in the Altair BASIC 3.2 manual, published in 1975. This morning I came across this article, in the March 31, 1976 issue of the…
Jeffrey Henning
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18
votes
1 answer
Could Pac-Man be replicated perfectly on the ZX Spectrum?
We all know that various ports of Pac-Man exist but my question is just for one specific computer. Could the Spectrum, with time and proper knowledge, run the Arcade version of Pac-Man despite it's Z80 processor running a 3.5 MHZ?
Let's assume that…
Vpirate21
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18
votes
3 answers
C64/PETSCII block graphic symbol: was there ever a logical reason for their "ASCII" codes?
You know those block graphic symbols that allows you to draw lines, corners, intersections, fine bar charts, etc. they are useful and one can do a lot of stuff, but their code arrangements always struck me as arbitrary / random. But then maybe I…
Gunther Schadow
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18
votes
8 answers
Were there any parallel port keyboards?
I was reading this QA ( Why is the clock frequency of the PS/2 keyboard protocol so high? ) and read in the replies that a high frequency was chosen (at least in-part) to reduce the latency between a keypress and the computer receiving the event.
I…
Dai
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votes
2 answers
Is there a Commodore 64 emulator that can profile running code?
I am developing some software for the Commodore 64, and I am concerned about its runspeed.
Is there an emulator that can report, after running my code, where exactly it spent most of its time? I'm happy to write some callback or something if that's…
Omar and Lorraine
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18
votes
2 answers
Meaning of $ and $$ in Modcomp assembly language
The Modcomp II was a 16-bit minicomputer circa 1970. As well as in FORTRAN IV, the Modcomp family could be programmed in assembly language, with syntax like this excerpt from Kermit for Modcomp:
HZS,POSIT *
…
Wayne Conrad
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18
votes
2 answers
How does Windows 9x determine which disk drivers correspond to which BIOS disks/DOS drive letters?
Windows 9x can employ two kinds of disk drivers: native protected-mode drivers and compatibility-mode DOS drivers, and the former are used in preference to the latter whenever possible. When Windows is started and native disk drivers are loaded,…
user3840170
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