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Last updated on Oct-18-2019 Download

MMC5 Bank Init Problem

MMC5 Bank Init Problem
by on (#46393)
I am working on a SMB1 (using SMBDIS) hack that uses MMC5, But the problem is that the banks are always initilized as fixed 8k bank instead of letting me choose from any other MMC5 bank method.

And the worst of it is that $8000-$9fff, $a000-$bfff, and $c000-$dfff is mirroring $e000-$ffff which is a fixed bank!

Is it the emulator(s)? I dunno, I just need a solution.

by on (#46395)
By default the MMC5 swaps the last 8k of PRG ROM at $8000, $a000, $c000 and $e000. From there you have to make some code to configure your bankswitching sheme yourself.

by on (#46404)
Also MMC5 as I recall has no fixed bank. Also when doing MMC5 PRG switching remember there is a PRG-RAM and PRG-ROM involved. I believe bit 7 has to be set to point to ROM rather than PRG-RAM for the area 8000$ to $DFFF. $6000 is always RAM and $E000 is always ROM I think.