Function new_m221 

pub fn new_m221(
    prg_rom: Box<[u8]>,
    chr_rom: Box<[u8]>,
    mirroring: Mirroring,
) -> Result<NtdecN625092, MapperError>

Mapper 221 (NTDEC N625092 multicart).

Errors

MapperError::Invalid on a bad PRG size.