REFORGE
Game Boy / Game Boy Color / F022
BEING VERIFIED

MBC3 RTC selection and latch state must not alias external RAM

STATUS
BEING VERIFIED
AREA
Timing / bus
RECORDED
undated
PUBLIC SOURCE
Research dossier / finding 022
RECORD ID
gb-f022
SNAPSHOT
a58ea4ac37c644e9

MBC3 types $0F-$13 now use a distinct 7-bit ROM-bank path and treat $08-$0C in the RAM/RTC select register as RTC registers rather than RAM banks. The bus models RAM/RTC enable, the 0 -> 1 latch edge, latched seconds/minutes/hours/day values, deterministic T-cycle advancement, halt, and day carry.

Raw traces, ROM material, local paths, and personal data are not part of this public record.