Wrong sprite patterns in Robocop (Sieco)

TomHarte / CLK

A latency-hating emulator of: the Acorn Electron and Archimedes, Amstrad CPC, Apple II/II+/IIe and early Macintosh, Atari 2600 and ST, ColecoVision, Enterprise 64/128, Commodore Vic-20 and Amiga, MSX 1/2, Oric 1/Atmos, early PC compatibles, Sega Master System, Sinclair ZX80/81 and ZX Spectrum.

MIT License

945 stars 52 forks source link

Wrong sprite patterns in Robocop (Sieco) #496

Closed grauw closed 6 years ago

grauw commented 6 years ago

Hey TomH, when I play SiecoRoboCop(1992)(Sieco).rom the sprites look wrong in CLK:

Compare:

TomHarte commented 6 years ago

My immediate guess is that sprites are in 8x8 mode but for some reason I'm painting them as though they're 16px wide. Two bytes are always fetched per sprite because that's true of a real TMS so it's most natural when reproducing its timing diagram to end up fetching two bytes, but for some reason I'm not discarding the second.

Just a guess. I'll look into it.

TomHarte commented 6 years ago

Yep, it was pretty much exactly that. After the pull request above, output is now as attached.