Posted By
Litwr
on 2013-08-02
16:12:05
|  Re: Z80 GUI: SymbOS
s1 and s2 are addresses of strings. I don't see any problem with this algorithm if a string will cross page boundaries.
BTW if we transfer proper X to subroutine than we get only average 0.5 of cycle. This makes z80:6502 speed ratio to 1:2.92 and code size ratio to 1:1.86.
If you have z80 code sample less than 32 bytes then I may try to write its 6502 equivalent.
[***edit]
gerliczer, thank you very much for the link. I've just read all 6 pages. However it contains theoretical discussion about old prices, definitions of CISC and RISC, ... I could also find very useful link about z80 wait states there. :-) My position is close to [youki] who wrote "I have to say that in that i don't like program in Z80. Not for technical reason , because Z80 is more or less as good than a 6502. But the RISC of the 6502 is more comfortable and more pleasant than the CISC of the Z80. That's purely subjective." I can't say that I don't like program in Z80 though - I am only seeking truth. :-)
So if we will count wait states (like at MSX, CPC, Spektrum, ...) then z80 code will require 67 cycles and this makes speed ration 1:3.2-3.4! Wow!
BTW I will also be happy if I can find information that z80 is even faster than 6502. What is wrong with small exercise of cycle counting for this computer forum for the entertainment? BTW I have Holidays. :-)
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