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1500 questions
17
votes
3 answers
For how long can you safely stop the clock on an NMOS 6502?
As with most NMOS processors, the NMOS versions of the 6502 (and even
earlier CMOS versions) do not have a static core. Thus, if you run the
clock too slowly or stop the clock for too long while doing clock
stretching, internal latches will lose…
cjs
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17
votes
1 answer
What is the protocol for bootstrapping a Game Boy Advance over a link cable?
One of my favorite features of the Game Boy Advance growing up was the ability for some games to be played multiplayer with just one cartridge - the first player would have the cartridge and all the other Game Boys would download their side of the…
TheHans255
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17
votes
1 answer
Why is the 8254's default rate 18.2 Hz?
The Intel 8253/8254 timer, in its default configuration, triggers IRQ0 18.2 times per second. Why this strange rate, and not something like 60 Hz (to match the most common video refresh rate) or 100 Hz (to give a round number)?
Mark
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17
votes
3 answers
x87 trigonometric instructions
The 8087 has instructions FPTAN and FPATAN, which are Partial Tangent and Partial Arctangent. The "partial" is presumably is to do with the range of the operands. For FPTAN the operand must be less than pi / 4 in absolute value.
Why was there this…
Single Malt
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17
votes
8 answers
Tool used to develop videogames with an Atari ST
I am a owner of Atari ST, and I would like to know software and tools used for the programmers for this computer to program mainly video games.
For example:
IDE used
Language (I think it was Basic, but I am not sure)
Websites of interest and…
inane
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17
votes
2 answers
DEC Alpha: why no 8/16-bit load/stores?
The first version of the DEC Alpha had no load/store instructions for 8 or 16-bit values; if you wanted to deal with data of such sizes, you had to do it by shifting and masking values in registers as necessary. (This restriction was abandoned later…
rwallace
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17
votes
3 answers
What are the difficulties in putting old AT style motherboards into modern ATX cases?
I have several 286, 386 and 486 motherboards that I would like to use. My problem is that while I have all of the components to make them functional, I don't have spare cases to put them in. Ideally, I would put them in period correct AT cases. …
cbmeeks
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17
votes
1 answer
Can you split resolutions and scrolling (horizontally) on an Amiga?
Some time back I asked if it was possible to get more than 8 sprites on a single scanline with the Amiga using a copper list. It seems it is quite possible indeed!
Now I am wondering if it is possible to also split the screen horizontally using a…
cbmeeks
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17
votes
5 answers
Has there ever been a instruction set architecture that did not require instruction decoding at all?
I am studying basic principles of instruction set architectures and am considering what it would take to not have any instruction decoding at all. I.e., all the control lines of the computer would be found directly in the bits of the instruction…
Gunther Schadow
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17
votes
4 answers
Running DOS, Windows 3, and Windows 98 from one FAT32 partition?
I'd like to setup a Windows 98 SE system that boots into the included MS-DOS 7.1 command line, and which can also run Windows 3.11. I've seen various disjointed posts online that suggest this is possible without using multiple boot partitions, and…
Brian H
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17
votes
1 answer
How does single-stepping on the 8086 interact with internal and external interrupts?
The 1979 version of the 8086 family user's manual is available at different places in the internet, see 1,2,3. It seems there is no newer version available. This manual documents the single-stepping feature in figure 2-29 on page 2-23 and figure…
Michael Karcher
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17
votes
2 answers
How to decode an audio file which contains an MSX BASIC program?
I have an audio file in WAV format, which supposedly comes from a cassette sound file. Moreover, it contains a BASIC program, but I don't know how to decode it. I have tried to convert the wav file to a tap file, but then I don't know how to convert…
Josemi
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17
votes
4 answers
How do I attach and use a CD-ROM drive to an Amiga?
I would like to add a CD-ROM drive to an Amiga.
I have not tried this for several years and I remember things failing to work without giving any useful errors, multiple choices of device and filesystem drivers, nagware popping up requesters on every…
Richard Downer
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17
votes
7 answers
8086 stack segment and avoiding overflow in interrupts
This is a followup to Could the Intel 8086 CPU have many segments in memory of the same type?
In the event of a hardware interrupt or user interrupt through the INT instruction, was there a risk that the user program had left the stack pointer close…
pjc50
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17
votes
5 answers
Does the Intel 8086 CPU have user mode and kernel mode?
Does the Intel 8086 CPU have user mode and kernel mode as modern CPUs do? and if it doesn't have user mode and kernel mode, does that mean that any user program written for the Intel 8086 CPU could do anything that the OS can do?
user14809
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