Questions tagged [intel]
Retrocomputing hardware and software created by Intel.
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What was the 6-bit length instruction(s) in the Intel iAPX 432?
The iAPX 432 was arguably the most complex processor architecture ever and a commercial failure for Intel. It was a stack machine with no visible general-purpose registers. It had hardware support ...
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What's the story behind the "mysterious" 486DX3?
As I was skimming through an old MS-DOS game's README, I stumbled upon this:
Therefore, we reccomend a newer 486-100 or better, preferably
with a large external cache. Best performance will result
...
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What floating point libraries were written to meet the IEEE 754 standard before it was accepted in 1985?
The IEEE 754 floating point arithmetic working group began in 1977 and was formally accepted in 1985. One of the original driving factors of the standard itself was Intel who wanted a standard to go ...
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Did the i186 use interrupt 6 for invalid opcodes?
I don't recall where from but at some point I was under the impression that the Intel 186 processor used interrupt 6 for invalid opcodes.
However, there's the HP 95LX that uses a NEC V20. NEC V20/V30 ...
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6
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How did AMD Am386 and Am486 outperform Intel's version of the same microprocessors?
This question is related to a previous one that has been asked here before (How did AMD's 386 and 486 perform like Intel's newer generation?)
My question is-two fold:
a) When AMD "...
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iRMX bootsector on a iRMX partition how to clone?
I have an old year 2000 instrument which has a 340MB hard drive. I am trying to clone the hard drive but I am having major issues.
First the instrument uses iRMX and MSDOS the bios is using the CHS ...
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What if ATX 12v P4 power connector was introduced 4 years earlier? [closed]
AT power supply handled +5 and +12 volts, +5 for ISA and processors, +12 for motors in disk drives.
In 1995 486DX2 was introduced with 3.3V core, so it derived that from a simple but inefficient ...
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3
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How much extra die area did a CMOS CPU take?
Starting in the late seventies, the microchip industry generally switched from NMOS to CMOS, primarily because CMOS circuits use less power, though they also have other advantages like more noise ...
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Intel "Kernel processor" or "OS Kernel"
I used to have an Intel data book from 1981. I gave it away to a friend, and he probably also lost it along the way.
In this book there was a data sheet for a component called "OS Kernel" or ...
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3
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When did the 386 overtake the 286?
The Intel 80386 was released in 1985, but was initially expensive, and took a long time to fully displace the earlier 80286 from the market; subjectively, I remember significant numbers of 286 ...
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Are there multiple models of the Intel 8089 IOP?
As far as I'm concerned there is only one model of the Intel 8089 (the D8089A-3).
I am not able to find any information on this. While the 8086,8088 and 8087 use the scheme of the last number (-3 in ...
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Why was the size of the 1989 Intel i860 (aka 80860) memory bus 64bit?
On Wikipedia I have read the i860 from 1989 memory bus was at least 64bits wide.
(It is the first CPU the Windows NT kernel was running on.)
I think even 10 years later (1999) most desktop CPUs were ...
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Does Intel Inboard 386/PC work on XT clone systems?
I don't have an Intel Inboard 386/PC, but I have a plan to buy it in the future. When I read its manual, there was no support for XT clones.
It says:
Install the Inboard 386/PC only in the computers ...
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28
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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 ...
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Why did the 8085 multiplex data with the low address byte?
Intel’s 8085 used bus multiplexing to stuff more functionality into 40 pins than would otherwise be possible. One of those pins, ALE, signals when the AD0…7 pins are outputting the low byte of the ...
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