8 May
2010
8 May
'10
1:37 p.m.
On Sat, 8 May 2010, Tony Duell wrote:
Ah, so a Z80 is a 16 bit processor (IX, IY, SP and PC are all 16 bits,
and there is no documented way to use half of them (Yes I do know about
some of the undocumented ways)).
The problem remains that we are trying to come up with a single
quantification for measuring something with multiple variable
characteristics.
If we were to grossly oversimplify,
and use the most "popular" quantifiers,
we would still have two characteristics to measure.
the 8080 is 8 bit software, 8 bit hardware
the 8088 is 16 bit software, 8 bit hardware.
the 8086 is 16 bit software, 16 bit hardware.
the 80286 is 16 bit software, 16 bit hardware.
the 80386SX is 32 bit software, 16 bit hardware.
the 80386DX is 32 bit software, 32 bit hardware.
the Sentry-70 is unknown.
But this does not invalidate the measuring systems used for different
types, and it is still trivially easy to come up with defensible ways to
measure with different end results.
Now, what are the definitions of "microcomputer", "minicomputer",
"mainframe"?
--
Grumpy Ol' Fred cisin at xenosoft.com
Is the size of the data bus irrelevant?
(There have been people who maintain that THAT is the measure of the
processor!)
They're wrong :-). The "size" of the CPU is defined by the size of the
internal registers. I am astonished there is actual discussion debating
this.
I think people who maintain the size of the data bus as being the
measure of a CPU are hardware people who have never optimized an inner
loop in machine code.
Conversely I could claim that those who calim the 8088 is a 16 bit
processor have never wire-wrapped the data bus connections to one, and
found there are only 8 to wire up.