Yokemate of Keyboards
Posts: 4977 from 2009/1/28
From: Delaware, USA
Quote:
Jeckel wrote:
Z80@4Mhz is *much* slower that 68000@7Mhz. Maybe 10 times slower (or even worse).
8x16 bit Z80 multiplication...
Mul16_8:
ld b,8
ld hl,0
Loop:
rra
jr nc,Jump
add hl,de
Jump:
sla e
rl d
djnz Loop
Yes, it is, and I'm a big fan of the 68000, but really its yet another apples and oranges comparison.
I can get better multiplication performance out of a Hitachi 6309 at half that speed (and I'm running those at 3.58 MHz in one project). Although...that can only do 8 x 8 multiplication or 16 x 16 multiplication (which obviously could be used for 8 x 16).
In any case, my point is...comparison of an 8 bit cpu to another 8 bit cpu would be more valid.
And that's what we have to remember, the Z80 is an earlier 8 bit design intended to compete with Intel's 8 bit cpus.
Its not fair to compare it to the 68000.
Edit - BTW, a 68000 processor is what you ADD to a Tandy Model 2 (which already has a Z80) in order to run something more powerful than CP/M, like Xenix. They're known as Model 16s or 6000s.
[ Edited by Jim 20.07.2017 - 10:42 ]"Never attribute to malice what can more readily explained by incompetence"
