MIT

This page is designed to allow for a quick look over all the drivers with a MACHINE_IMPERFECT_TIMING flag by giving, as much as possible, an idea on the amount of effort needed to fix them.

acorn/aristmk5

Games are running at double speed.

alpha/alpha68k

goldmedl, goldmedla, goldmedlb - Dash events timers relies on MCU irq timings, which can't be accurate til the MCU is decapped and emulated.

alpha/alpha68k_n

sstingry - Super Stingray MCU irq controls timer speed. The MCU has been hooked up but the clock is almost certainly wrong.

chess/tasc

More accurate dynamic cpu clock divider is needed.

dataeast/progolf

MC6845 timings are wrong.

fidel/as12

Seems a little bit slower than the real machine. Currently, a dummy timer workaround is needed, or it's much worse. Is the problem here is due to timing of CPU addressbus changes?

fidel/eag68k

feagv10 - V10 CPU emulation is too slow, MAME 68040 opcode timing is same as 68030 but in reality it is much faster, same goes for V11 of course (see below).

feagv11 - V11 CPU should be M68EC060, not yet emulated. Now using M68EC040 in its place at twice the frequency due to lack of superscalar.

fidel/elite

fpres/feas irq active time needs verifying.

fidel/sc12

Seems a little bit slower than the real machine. Currently, a dummy timer workaround is needed, or it's much worse. Is the problem here is due to timing of CPU addressbus changes?

hegenerglaser/modular

Waitstates emulation is preliminary.

konami/konamigs

ddrkids - Songs desync.

konami/konamim2

Games are running slower than they should.

mephisto/mm2

mm4tk, mm5p - They need proper emulation of the TurboKit (it's not as simple as a CPU overclock plus ROM patch).

misc/cv1k

Games are running faster than on real hardware.

misc/monon_color

Clock divider unknown.

nichibutsu/clshroad

clshroad and clones - Main and sound CPUs synching isn't perfect.

nintendo/cothello

CPU speed is wrong, it's likely running at 1.79MHz. But that's way too fast compared to videos of the game. 0.9MHz(XTAL/4) is also too fast. It's probably due to the M58741P HOLD pin halting the 8080, which is not emulated.

saitek/risc2500

More accurate dynamic cpu clock divider is needed.

sega/sega_beena

Misses storyware layout.

subsino/lastfght

Blitter timings are guessed.

taito/taitojc

Games are running at wrong speed(unthrottled?) compared to PCB recordings, easily noticeable on sidebs/sidebs2, for example the selection screens are too fast, and the driving is almost twice as slow.

tvgames/spg2xx_shredmjr

Bad music timings (too slow).

vectorgraphic/vector4

CPU wait states, S-100 interrupts and ready aren't emulated.