Wonderland Dizzy Sprite Corruption

[muckypaws]

Hey, Loved your emulator and managed to DL before you sadly pulled it from the store, but understand your concerns. Hopefully you're still developing the emulator.

I've tried the Wonderland Dizzy NES Rom which is available for free from the Oliver Twins website (Authors of the game).

https://yolkfolk.com/wonderland-dizzy/

Weirdly, the Main Sprites, are rotated on screen when they are active, please see the screenshots attached.

Other emulators, I don't see this issue.

Kind Regards and very nice work btw 👍

WonderlandDizzy(NES).zip

[tsalvo]

Thank you for this! The game seems to be detecting the ROM header the same way as FCEUX does, so I think that part is working:

 PRG ROM: 16 x 16KiB = 256 KiB
 CHR ROM: 0 x  8KiB = 0 KiB
 Mapper #: 2
 Mapper name: UNROM
 Mirroring: Vertical
 Battery-backed: No
 Trained: No

I'll double-check that I'm implementing the UNROM mapper correctly according to spec. At a glance, that mapper is pretty simple, so I think it's more likely I have some timing or logic issue with the PPU, which might take me a little longer to figure out. but I'll give it a try 😄