banking prg rom to $6000

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banking prg rom to $6000
by on (#192462)
Which mappers support rom banking at $6000? I know FME7 does but I can't find any compiled info on others.

I know MMC3 doesn't support this- would it be possible to alter a board to make it support this? What would it take? I guess you'd need at least an external latch for the bank number which makes it tricky to catch with the select/data registers on the MMC3. Maybe it could be done as a hybrid with discrete UNROM style banking?
Re: banking prg rom to $6000
by on (#192463)
The JY Company mappers (90/209/211), FME-7, NROM-368, and several of the pirate FDS ports (e.g. m40, m50).

Pedantically, you could probably consider the FDS, too, but that's a weird special case.

It would be possible to replace the PRG RAM on any board with an 8KiB ROM, but kind of daft. And if you're not going to use something that's an exact copy of an existing mapper, I'd strongly recommend revisiting the whole design specification instead.