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Mapper 57 - fix mirroring bug, and support dipswitches

This commit is contained in:
adelikat 2016-10-17 08:01:11 -05:00
parent d0b57a02ca
commit 8debec4039
1 changed files with 12 additions and 45 deletions
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57
BizHawk.Emulation.Cores/Consoles/Nintendo/NES/Boards/Mapper057.cs
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@ -5,55 +5,15 @@ namespace BizHawk.Emulation.Cores.Nintendo.NES
{
public sealed class Mapper057 : NES.NESBoardBase
{
/*
Here are Disch's original notes:
========================
= Mapper 057 =
========================
Example Games:
--------------------------
GK 47-in-1
6-in-1 (SuperGK)
Registers:
---------------------------
Range,Mask: $8000-FFFF, $8800
$8000: [.H.. .AAA]
H = High bit of CHR reg (bit 4)
A = Low 3 bits of CHR Reg (OR with 'B' bits)
$8800: [PPPO MBBB]
P = PRG Reg
O = PRG Mode
M = Mirroring (0=Vert, 1=Horz)
B = Low 3 bits of CHR Reg (OR with 'A' bits)
CHR Setup:
---------------------------
'A' and 'B' bits combine with an OR to get the low 3 bits of the desired page, and the 'H' bit is the high
bit. This 4-bit value selects an 8k page @ $0000
PRG Setup:
---------------------------
$8000 $A000 $C000 $E000
+---------------+---------------+
PRG Mode 0: | $8800 | $8800 |
+-------------------------------+
PRG Mode 1: | <$8800> |
+-------------------------------+
*/
// http://wiki.nesdev.com/w/index.php/INES_Mapper_057
bool prg_mode = false;
int chr_reg_low_0, chr_reg_low_1, chr_reg;
int prg_reg;
[MapperProp]
public int Mapper57_DipSwitch = 0;
public override bool Configure(NES.EDetectionOrigin origin)
{
switch (Cart.board_type)
@ -66,6 +26,8 @@ namespace BizHawk.Emulation.Cores.Nintendo.NES
SetMirrorType(EMirrorType.Horizontal);
AutoMapperProps.Apply(this);
return true;
}
@ -94,7 +56,7 @@ namespace BizHawk.Emulation.Cores.Nintendo.NES
prg_mode = value.Bit(4);
chr_reg_low_1 = (value & 0x07);
if (addr.Bit(3))
if (value.Bit(3))
{
SetMirrorType(EMirrorType.Horizontal);
}
@ -130,5 +92,10 @@ namespace BizHawk.Emulation.Cores.Nintendo.NES
}
return base.ReadPPU(addr);
}
public override byte ReadWRAM(int addr)
{
return (byte)(Mapper57_DipSwitch & 3);
}
}
}