BizHawk/BizHawk.Emulation/Consoles/Atari/2600/Mappers/mX07.cs

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using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
namespace BizHawk.Emulation.Consoles.Atari._2600
{
/*
X07 (Atariage)
-----
Apparently, this was only used on one cart: Stella's Stocking.
Similar to EF, there are 16 4K banks, for a total of up to 64K of ROM.
The addresses to select banks is below the ROM area, however.
The following TWO masks are used:
A13 A0
----------------
0 1xxx nnnn 1101
This means the address 80B selects bank 0, 81B selects bank 1, etc.
In addition to this, there is another way:
A13 A0
----------------
0 0xxx 0nxx xxxx
This is somewhat special purpose: Accessing here does nothing, unless one of the
last two banks are selected (banks 14 or 15). In that case, the new bank is:
111n i.e. accessing 0000 will select bank 14 (Eh, 1110b) while accessing 0040
will select bank 15 (Fh, 1111b). This allows for bankswitching by accessing
TIA registers at 00-3F or 40-7F without incurring any overhead.
*/
class mX07 : MapperBase
{
}
}