Talk:INES Mapper 099

Minimal discrete logic clone

A 74138, selecting on M2, A14, A4, and A1 high; R/W and A0 low, and a 7474 (or any larger latch). Maps the write-only register at every address [4-7C-F].[13579BDF][26AE]. Conflicts on writes to $4012 and DualSystem games that communicate using RAM. Using a 74161 or any other latch with an additional active-low enable would remove the conflict with the DualSystem RAM; however, there's no obvious place to get an extra active-high enable to prevent the conflict with $4012. —Lidnariq (talk) 16:15, 31 October 2013 (MDT)