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Add description for out of bounds MBC ram access #594

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Add description for out of bounds MBC ram access #594

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e9dedf0
Add description for out of bounds MBC ram access
alloncm Mar 22, 2025
10955e0
Change mbc ram access formula
alloncm Apr 5, 2025
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6 changes: 6 additions & 0 deletions src/MBCs.md
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Expand Up @@ -20,3 +20,9 @@ so, it might be nevertheless possible to use Double Speed during periods
which use only code and data which is located in internal RAM. Despite the
above, a self-made MBC1-EPROM card appears to work stable and fine even in
Double Speed Mode.

## MBC Out Of Bounds RAM Access

On most of the MBC's in case an out of bounds address is accessed (selecting unmapped RAM bank),
only the mapped bits from the address will be used.
The actual address being accessed can be calculated using this formula: `address % max_ram_size`.