Questions tagged [microprocessor]
The microprocessor tag has no usage guidance.
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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 aspects of microprocessor ISAs have been patented?
A key objective of RISC-V was that every aspect of the ISA must be based on an expired patent. It was felt that this is the only truly reliable defense against patent lawsuits.
It is surprising that ...
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How could the Intel 4004 address 640 bytes if it was only 4-bit?
I am reading Computer Organization and Architecture, 10th ed. by William Stallings and I found this on page 26.
where it says the addressable memory of 4004 is 640 bytes.
But it appears that the ...
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How did Z8000 implement mul/div in few transistors with no microcode?
The Z8000 was Zilog's entry in the 16-bit microprocessor market; it was unsuccessful in large part, as I understand it, because it took too long to debug. According to https://thechipletter.substack....
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Why does my Mikrolab randomly freeze and unfreeze, and what can I do about it?
I've started using my Soviet Mikrolab KR580IK80 (a clone of the Hewlett Packard 5036A) again, and I've noticed some behaviour which it used to exhibit but now it seems more frequent. Basically after ...
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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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Would compare-and-branch have added an extra cycle on ARM-1?
The ARM-1 was an early RISC CPU, designed in 1986 (and even more typical of early RISC design constraints than the year would suggest, since Acorn didn't have the budget to pay for the latest process ...
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Does any computer resemble the model taught in UK secondary education?
In UK secondary education, there's a model called the fetch-execute cycle, which describes how computers work. (See: Isaac CS; Bitesize GCSE, Higher; Teach CS.) As I understand it:
The processor has ...
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Were there any enhancement chips that vastly outperformed the main CPU?
Were there any enhancement chips in officially-released games that were CPUs themselves and which ran the game code itself, relegating the role of the main CPU to that of a thin client?
To elaborate, ...
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How did old computers address far more than 64K of memory despite only having a 16 bit address bus?
I have an old Sharp PC-G830 pocket computer from the '80s that has 32K of RAM and 256K of ROM. I also have a simple single board computer I built with 128K of RAM and a few megabytes of ROM from a ...
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How the technology keeps improving [closed]
How does the technology keep improving despite having everything discovered already? I mean the same sized chips and electronics are used from year to year but with every new version of the main board ...
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Why has the Intel Itanium failed to take on the world? [closed]
Last summer, the Itanium has finally been discontinued, twenty years after its release. It was a promising technology, but in the end it turned out to not really be the case.
Beside a few niche ...
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McDonnell-Douglas 16-bit microprocessor?
I've been working on the NatSemi PACE article and I'm trying to track down a bit of trivia... someone inserted a statement:
McDonnell Douglas produced a classified military 16-bit processor called ...
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What is the relation between external clock and internal states in the 68000?
(I'm assuming a memory cycle of 500 ns, without wait states.)
According to the 68000 bus diagram, there are 4 CPU cycles for a memory cycle, so an external frequency of 8 MHz. However, things are ...
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The Slowest Microprocessor [closed]
I've read that Z3, first electromechanical general purpose computer operated at a frequency of about 5–10 Hz, and the ENIAC had a 100 kHz clock, though each instruction took 20 cycles.
What ...
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