Talk:INES
How does a PlayChoice hint screen work? --Zzo38 19:08, 21 September 2012 (MDT)
Last 4
Should this be "if the last 5 bytes are not all zero"? "A general rule of thumb: if the last 4 bytes are not all zero, and the header is not marked for NES 2.0 format, an emulator should either mask off the upper 4 bits of the mapper number or simply refuse to load the ROM." -Ulfalizer (talk) 03:45, 14 July 2013 (MDT)
- When I wrote 4 as the rule of thumb, I didn't know how many not-widely-adopted extensions to original iNES were floating around, and I guessed that one or more might have used byte 11 for something, but all of the ROMs I saw with DiskDude and similar tags had at least something in the last four bytes of the header. --Tepples (talk) 07:48, 14 July 2013 (MDT)
- Nestopia checks the last 6, and clears/ignores the last 9. (It also actually does pay attention to bytes 8 and 9)—Lidnariq (talk) 11:21, 14 July 2013 (MDT)
- If the header contains "DiskDude!" or one of those other things (I forget now, but I knew at one time and figured this out), then bit2 of flags 7 will be set; otherwise bit2 and bit3 should both be cleared. This may be another way. --Zzo38 (talk) 19:51, 20 August 2013 (MDT)
4-screen mirroring
Reference needed I'm afraid.
"Theoretically bit 3 could be used for most mappers that had hard-wired mirroring to transparently provide 4KB of VRAM for 4-screen instead. However, many emulators will ignore this bit except for mappers with prior 4-screen variations."
I'm fairly confident most emulators will happily gives you 4-screen mirroring when asked for it, even if they are in mappers where such a possibility wasn't used. I remember at some point considering using 4-screen mirroring with CNROM and it worked well. Bregalad (talk) 01:55, 13 January 2019 (MST)
