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Old 21 September 2013, 10:57   #98
amilo3438
Amiga 500 User
 
Join Date: Jun 2013
Location: EU
Posts: 1,114
Quote:
Originally Posted by Toni Wilen View Post
No, there is still nothing interesting, sorry

CPU speed did change. Multiplier = CPU clock rate is syncronized to chipset clock (sync clock). Value = manual value, async clock. Difference is not as small as you think it is. Even single cycle change can make huge difference during blitter accesses.
Mentioned this as found both to be under same "Cycle-exact CPU Emulation Speed" option ... very confusing ?!

I always thought that cycle-exact = sync clock to chipset.


EDIT:Would it mean that cycle-exact isnt same as cycle-accurate then?!

According to this in WinUAE there are then 4 possible modes regarding A500 CPU Emulation Speed, right?

1) Cycle-exact sync clock (CE=ON, Multiplier CPU clock) = best compatibility mode!

2) Cycle-exact async clock (CE=ON, Custom CPU clock)

3) Approximate A500/1200 (CE=OFF)

4) Fastest possible (CE=OFF) = lowest compatibility mode!


EDIT2: Does cycle-exact should mean to synchronize processor between opcodes and cycle-accurate between cycles ?!

EDIT3: When comparing config. files of "CE=ON, Multiplier CPU clock" and "CE=ON, Custom CPU clock" found only one option different, else is same:

cpu_speed=real
cpu_throttle=0.0
cpu_type=68000
cpu_model=68000
cpu_compatible=true
cpu_24bit_addressing=true
cpu_multiplier=2
cpu_cycle_exact=true
blitter_cycle_exact=true
cycle_exact=true

cpu_speed=real
cpu_throttle=0.0
cpu_type=68000
cpu_model=68000
cpu_compatible=true
cpu_24bit_addressing=true
cpu_frequency=7093790
cpu_cycle_exact=true
blitter_cycle_exact=true
cycle_exact=true

So, CPU and blitter is cycle-exact on both ... but 1st mode work in sync and 2nd mode work in async between CPU and blitter, right ?

Last edited by amilo3438; 21 September 2013 at 15:02.
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