diff options
Diffstat (limited to 'GPU.cpp')
| -rw-r--r-- | GPU.cpp | 29 |
1 files changed, 27 insertions, 2 deletions
@@ -113,8 +113,33 @@ void Reset() } -// VRAM mapping shit. -// TODO eventually: work out priority orders in case of overlaps. there _are_ games that map overlapping banks. +// VRAM mapping notes +// +// mirroring: +// unmapped range reads zero +// LCD is mirrored every 0x100000 bytes, the gap between each mirror reads zero +// ABG: +// bank A,B,C,D,E mirror every 0x80000 bytes +// bank F,G mirror at base+0x8000, mirror every 0x80000 bytes +// AOBJ: +// bank A,B,E mirror every 0x40000 bytes +// bank F,G mirror at base+0x8000, mirror every 0x40000 bytes +// BBG: +// bank C mirrors every 0x20000 bytes +// bank H mirrors every 0x10000 bytes +// bank I mirrors at base+0x4000, mirrors every 0x10000 bytes +// BOBJ: +// bank D mirrors every 0x20000 bytes +// bank I mirrors every 0x4000 bytes +// +// untested: +// ARM7 (TODO) +// extended palette (mirroring doesn't apply) +// texture/texpal (does mirroring apply?) +// +// overlap: +// when reading: values are read from each bank and ORed together +// when writing: value is written to each bank void MapVRAM_AB(u32 bank, u8 cnt) { |