a.k.a. why MESS is no more light years away from NEStopia (even if we're still far from catching it
Dear all, I finally finished to clean up the NES driver passing through all the supported mappers (and some previously unsupported ones)
A verbose description of the improvements can be found in the following blog entries (be warned: there are around 40 snaps in each page, so be patient if you have a slow connection)http://mamedev.emulab.it/etabeta/?p=138
Hence, I think it's time to open this new thread to collect impressions and reports about possible bugs (every problem worse than 1-line graphical glitches are worth mention if not listed below), before filling up bugzilla of already known problems
I include a list of known issues (as described in the driver itself). I hope that all the remaining problems could be reduced to one of these entries or to unsupported mappers.
Known issues on specific mappers:
* 000 F1 Race requires more precise PPU timing. It currently has plenty of 1-line glitches.
* 001 AD&D Hillsfar and Bill & Ted are broken. We need to ignore the case of writes happening on 2
consecutive CPU cycles because these games use dirty tricks to reset counters (see note in mapper1_w)
* 001, 155 We don't handle (yet) WRAM enable/disable bit
* 002, 003, 094, 097, 152 Bus conflict?
* 005 has issues (see e.g. Just Breed or Metal Slader Glory), RAM banking needs hardware flags to determine size
* 014 in-game graphics is glitched
* 015 Shanghai Tycoon has corrupted graphics
* 033 has still some graphics problem (e.g. missing text in Akira)
* 034 Impossible Mission II does not show graphics
* 038 seems to miss inputs. separate reads?
* 039 Study n Game 32 in 1 misses keyboard and starts differently than in NEStopia
* 042 Ai Senshi Nicol has broken graphics (our Mapper 42 implementation does not handle CHR banks)
* 051 only half of the games work
* 064 has many IRQ problems (due to the way we implement CPU based IRQ) - see Skull & Crossbones.
Klax has problems as well (even if it uses scanline based IRQ, according to Disch's docs).
* 067 some 1-line glitches that cannot be solved without a better implementation for cycle-based IRQs
* 071 Fire Hawk is not properly working (it requires one hack to support both boards using this mapper)
* 072, 086, 092 lack samples support (maybe others as well)
* 073 16 bit IRQ mode is not implemented
* 077 Requires 4-screen mirroring. Currently, it is very glitchy
* 083 has serious glitches
* 096 is preliminary (no correct chr switch in connection to PPU)
* 104 Not all the games work
* 107 Are the scrolling glitches (check status bar) correct? NEStopia behaves similarly
* 112 Master Shooter is not working and misses some graphics
* 117 In-game glitches
* 119 Pin Bot has glitches when the ball is in the upper half of the screen
* 133 Qi Wang starts with corrupted graphics (ingame seems better)
* 143 are Dancing Block borders (in the intro) correct?
* 153 Famicom Jump II variant is not working, for some reason
* 158 In addition to IRQ problems (same as 64), mirroring was just a guess (wrong?). info needed!
* 164 preliminary - no sprites?
* 176 has some graphics problem
* 178 Fan Kong Jin Ying is not working (but not even in NEStopia)
* 180 Crazy Climber controller?
* 185 we emulate it like plain Mapper 3, but it's not: Mighty BombJack and Seicross don't work
* 187, 198, 208, 215 have some PRG banking issues - preliminary!
* 188 needs mic input (reads from 0x6000-0x7fff)
* 197 Super Fighter 3 has some glitch in-game (maybe mirroring?)
* 222 is only preliminar (wrong IRQ, mirroring or CHR banking?)
* 225 115-in-1 has glitches in the menu (games seem fine)
* 228 seems wrong. e.g. Action52 starts with a game rather than in the menu
* 229 is preliminary
* 230 not working yet (needs a value to flip at reset)
* 232 has graphics glitches
* 241 Commandos is not working (but not even in NEStopia)
* 242 In Dragon Quest VIII graphics of the main character is not drawn (it seems similar to Shanghai Tycoon [map15]
because in place of the missing graphics we get glitches in the left border)
* 249 only half of the games work (and Du Bao Ying Hao seems to suffer the same problem as DQ8 and Shanghai Tycoon)
* 252 shows logo, but doesn't reach the game
* 255 does not really select game (same in NEStopia apparently)
just a few snaps to show off