Talk:MMC3: Difference between revisions
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When PRG RAM is accessed via $6000-$7FFF, what does the MMC3 put on the upper PRG ROM address lines? --[[User:Tepples|Tepples]] 23:24, 20 April 2011 (UTC) | When PRG RAM is accessed via $6000-$7FFF, what does the MMC3 put on the upper PRG ROM address lines? --[[User:Tepples|Tepples]] 23:24, 20 April 2011 (UTC) | ||
: Ideally, the MMC3 wouldn't put anything on the ROM address lines. :P Either way, if the CPU is accessing $6000-7FFF, I'd imagine whatever chip is selected would see %011xxxxx xxxxxxxx on its address lines. RAM would just see the x part, and whatever mapper-supplemented upper address lines if the RAM is bankswitched. | |||
Revision as of 04:05, 21 April 2011
There's some documentation about the differences between MMC3 revisions here: [1] I'll add them in at some point, if nobody else does. --Drag 18:00, 19 April 2011 (UTC)
PRG RAM bank behavior
When PRG RAM is accessed via $6000-$7FFF, what does the MMC3 put on the upper PRG ROM address lines? --Tepples 23:24, 20 April 2011 (UTC)
- Ideally, the MMC3 wouldn't put anything on the ROM address lines. :P Either way, if the CPU is accessing $6000-7FFF, I'd imagine whatever chip is selected would see %011xxxxx xxxxxxxx on its address lines. RAM would just see the x part, and whatever mapper-supplemented upper address lines if the RAM is bankswitched.
