Difference between revisions of "Talk:Master System emulators"
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Mednafen can also emulate SMS, according to [[Mednafen]]. | Mednafen can also emulate SMS, according to [[Mednafen]]. | ||
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+ | == Removal of the Genesis, CD, and 32X columms. == | ||
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+ | This page is about the Master System and Game Gear emulators. I would also suggest a name change to Master System/Game Gear emulators if people are ok with it. --[[User:LilShootDawg|LilShootDawg]] ([[User talk:LilShootDawg|talk]]) 09:52, 8 November 2019 (EST) |
Revision as of 14:52, 8 November 2019
Contents
TwoMBit is not cycle accurate
It claims to be, but most likely predates the latest VDP discoveries. In particular:
See the documentation by Mask of Destiny here. The VDP has a certain number of 'external slots' per line — these are when it will permit a CPU-directed memory access to occur. The net timing cost for the CPU to put a byte into video memory is: (i) a fixed delay; plus (ii) the variable amount of time until the next external slot. It *is not a fixed amount*.
However, check out TwoMBit's VDP.cpp: the one-two of initDelay() and updateDelay(), initiated by write_port_BE(...), apply a fixed cost to memory accesses of the worst-case access time.
TwoMBit therefore does not accurately model the real hardware.
Any one deviation is sufficient to establish the point, but I note also just from a cursory glance that it doesn't calculate sprite overflow as the raster runs, so will set that flag at the wrong time.
For these reasons, I have demoted its table entry from 'cycle' accurate to 'very high' accuracy. — Tommy (talk) 22:01, 2 March 2019 (EST)
Where's Exodus?
Why isn't Exodus on this page?
Mednafen
Mednafen can also emulate SMS, according to Mednafen.
Removal of the Genesis, CD, and 32X columms.
This page is about the Master System and Game Gear emulators. I would also suggest a name change to Master System/Game Gear emulators if people are ok with it. --LilShootDawg (talk) 09:52, 8 November 2019 (EST)