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ekeeke / Genesis-Plus-GX

An enhanced port of Genesis Plus - accurate & portable Sega 8/16 bit emulator
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[Wii] Increase speed overclock limit to x8.0 (800%), Wii U recommended #488

Closed saulfabregwiivc closed 1 year ago

saulfabregwiivc commented 1 year ago

This modification allows to have the overclock settings' speed limit for M68K and sub M68K at x8.0 (800%) instead of x3.0 (300%). (see issue https://github.com/ekeeke/Genesis-Plus-GX/issues/485, by any reason it was confused with Libretro stuff when he/she talked about the general GX port) For use these new speeds it is highly recommendable to use a Wii U with vWii overclocked.

These speeds beyond x3.0 (300%) will stay hidden on the GameCube port's GUI, as the CPU is not powerful enough.

ekeeke commented 1 year ago

Two things: 1) DM68K_OVERCLOCK_SHIFT=70 makes no sense as this is a bit shifting value and 20 bit shift is calculated to allow proper 68k cycle instruction calculation within the 32-bit limit

2) Increasing MAIN 68K overclock above 700% makes no sense as the limit is the master clock speed (m68k is originally 1/7 of master clock speed so overclock cannot go beyond 7x, which correspond to 53 MHz anyway, so well beyond anything realistic regarding 68k overclock). Similarely, SUB 68K overclock will be limited to 4x i e 50MHz which is Mega CD master clock speed

If you really want increased overclock for the Wii port, I would recommend opening an issue/enhancement request instead (the issue you are referring to was actually related to the libretro port of Genesis Plus GX)

saulfabregwiivc commented 1 year ago

Ok then.