Smallest mappable window

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Smallest mappable window
by on (#48855)
What is the smallest window of memory that can be individually mapped by any mapper

by on (#48857)
Technically the only limit is on a byte level, So it's theoretically possible for every byte to be individually mapped.

Realistically, the smallest mappings I've seen are 1K for CHR, 8K for PRG-ROM in actual ROMs, but 4K for NSFs.

Additionally, MMC6 has 1K of PRG-RAM that gets mirrored across 4K address space... and each 512 bytes of that 1K can be individually disabled.

For purposes of emulation, I just use 1K CHR and 4K PRG, and have special read/write handlers to handle the other rare instances.