Linked by Nicholas Blachford on Wed 9th Jul 2003 16:43 UTC
Talk, Rumors, X Versus Y This article started life when I was asked to write a comparison of x86 and PowerPC CPUs for work. We produce PowerPC based systems and are often asked why we use PowerPC CPUs instead of x86 so a comparison is rather useful. While I have had an interest in CPUs for quite some time but I have never explored this issue in any detail so writing the document proved an interesting exercise. I thought my conclusions would be of interest to OSNews readers so I've done more research and written this new, rather more detailed article. This article is concerned with the technical differences between the families not the market differences.
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re: sabrina & bobby
by goo.. on Wed 9th Jul 2003 20:30 UTC

Sab: I haven't read the article past the quote I made. I like wasting my time proving people wrong butI don't like wasting my time for absolutely nothing. The sentence was a sign of things to come and I didn't even bother to read the remaining hence didn't even know it was slanted towards PPC until reading comments. As such my windows fanboyness (which I don't use and not a fan of) is a misunderstanding on your part.

Bob: 4004 and 8086 are not related (except in the lame MS joke that ends with "... 1 bit of competition") either. 4004 has no architectural descendants. 8088 and 8086 are similar (even same on software level) but 8080 is a different beast. Compare:
8080: interrupt are handled via a specilized function call (1 byte long. except that identical to CALL)
8086: interrupts are handled via special all-register stack dumping instructions
8080: Flat 16 bit addressing with 8 bit GP registers.
8086: Segmented 20 bit addressing with 16 bit registers. No real general purpose registers except accumulator
8080: No integer arithmetic except ADD and SUB, no loop, floating point, indexed or string handling instructions
8086: You know what 8086 has
Of course intel didn't start over as if 8086 was their first CPU, there is bound to be more similarities between 8080 and 8086, say, compared to 6502 and 8086. However you can't even trivially modify 8080 code to compile on 8086. Names 808 0 and 808 6 imply a stronger link that doesn't exist. See if you can read the following 8080 code (CP/M operating system manual, 1982 edition, page 212-213, lines 186-199)
(cpmspt, noovf, unatrk are labels)

inr m
mov a,m
cpi cpmspt
jc noovf

mvi m,o
lhld unatrk
inx h
shld unatrk

xra a