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GB: Improved serial link emulation stub

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This commit is contained in:
Sour 2020-05-27 19:54:12 -04:00
parent 5e6e9e41aa
commit 4b86601faf
4 changed files with 36 additions and 9 deletions
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12
Core/GbCpu.cpp
View file

@ -16,17 +16,19 @@ GbCpu::GbCpu(Console* console, Gameboy* gameboy, GbMemoryManager* memoryManager)
if(_gameboy->UseBootRom()) { if(_gameboy->UseBootRom()) {
_state.PC = 0; _state.PC = 0;
_state.SP = 0xFFFF; _state.SP = 0xFFFF;
_state.CycleCount = 8; //Makes boot_sclk_align serial test pass
} else { } else {
_state.PC = 0x100; _state.PC = 0x100;
_state.SP = 0xFFFE; _state.SP = 0xFFFE;
_state.A = _gameboy->IsCgb() ? 0x11 : 0x01; _state.A = _gameboy->IsCgb() ? 0x11 : 0x01;
_state.B = 0x00; _state.B = 0x00;
_state.C = 0x13; _state.C = _gameboy->IsCgb() ? 0x00 : 0x13;
_state.D = 0x00; _state.D = 0x00;
_state.E = 0xD8; _state.E = _gameboy->IsCgb() ? 0x08 : 0xD8;
_state.H = 0x01; _state.H = _gameboy->IsCgb() ? 0x00 : 0x01;
_state.L = 0x4D; _state.L = _gameboy->IsCgb() ? 0x7C : 0x4D;
_state.Flags = 0xB0; _state.Flags = _gameboy->IsCgb() ? 0x80 : 0xB0;
_state.CycleCount = _gameboy->IsCgb() ? 13051516 : 23440332;
} }
} }

25
Core/GbMemoryManager.cpp
View file

@ -73,6 +73,13 @@ void GbMemoryManager::Exec()
_timer->Exec(); _timer->Exec();
_ppu->Exec(); _ppu->Exec();
_dmaController->Exec(); _dmaController->Exec();
if(_state.SerialBitCount && (_gameboy->GetCycleCount() & 0x1FF) == 0) {
_state.SerialData = (_state.SerialData << 1) | 0x01;
if(--_state.SerialBitCount == 0) {
RequestIrq(GbIrqSource::Serial);
}
}
} }
void GbMemoryManager::MapRegisters(uint16_t start, uint16_t end, RegisterAccess access) void GbMemoryManager::MapRegisters(uint16_t start, uint16_t end, RegisterAccess access)
@ -238,8 +245,8 @@ uint8_t GbMemoryManager::ReadRegister(uint16_t addr)
switch(addr) { switch(addr) {
case 0xFF00: return ReadInputPort(); break; case 0xFF00: return ReadInputPort(); break;
case 0xFF01: return 0; //SB - Serial transfer data (R/W) case 0xFF01: return _state.SerialData; //SB - Serial transfer data (R/W)
case 0xFF02: return 0x7E; //SC - Serial Transfer Control (R/W) case 0xFF02: return _state.SerialControl | ~(_gameboy->IsCgb() ? 0x83 : 0x81); //SC - Serial Transfer Control (R/W)
case 0xFF04: case 0xFF05: case 0xFF06: case 0xFF07: case 0xFF04: case 0xFF05: case 0xFF06: case 0xFF07:
return _timer->Read(addr); return _timer->Read(addr);
@ -315,7 +322,16 @@ void GbMemoryManager::WriteRegister(uint16_t addr, uint8_t value)
//00-0F //00-0F
switch(addr) { switch(addr) {
case 0xFF00: _state.InputSelect = value; break; case 0xFF00: _state.InputSelect = value; break;
case 0xFF01: break; //Serial case 0xFF01: _state.SerialData = value; break; //FF01 - SB - Serial transfer data (R/W)
case 0xFF02:
//FF02 - SC - Serial Transfer Control (R/W)
_state.SerialControl = value & (_gameboy->IsCgb() ? 0x83 : 0x81);
if((_state.SerialControl & 0x80) && (_state.SerialControl & 0x01)) {
_state.SerialBitCount = 8;
} else {
_state.SerialBitCount = 0;
}
break;
case 0xFF04: case 0xFF05: case 0xFF06: case 0xFF07: case 0xFF04: case 0xFF05: case 0xFF06: case 0xFF07:
_timer->Write(addr, value); _timer->Write(addr, value);
@ -412,7 +428,8 @@ void GbMemoryManager::Serialize(Serializer& s)
{ {
s.Stream( s.Stream(
_state.DisableBootRom, _state.IrqEnabled, _state.IrqRequests, _state.InputSelect, _state.DisableBootRom, _state.IrqEnabled, _state.IrqRequests, _state.InputSelect,
_state.ApuCycleCount, _state.CgbHighSpeed, _state.CgbSwitchSpeedRequest, _state.CgbWorkRamBank _state.ApuCycleCount, _state.CgbHighSpeed, _state.CgbSwitchSpeedRequest, _state.CgbWorkRamBank,
_state.SerialData, _state.SerialControl, _state.SerialBitCount
); );
s.StreamArray(_state.MemoryType, 0x100); s.StreamArray(_state.MemoryType, 0x100);
s.StreamArray(_state.MemoryOffset, 0x100); s.StreamArray(_state.MemoryOffset, 0x100);

4
Core/GbTypes.h
View file

@ -349,6 +349,10 @@ struct GbMemoryManagerState
uint8_t IrqEnabled; uint8_t IrqEnabled;
uint8_t InputSelect; uint8_t InputSelect;
uint8_t SerialData;
uint8_t SerialControl;
uint8_t SerialBitCount;
bool IsReadRegister[0x100]; bool IsReadRegister[0x100];
bool IsWriteRegister[0x100]; bool IsWriteRegister[0x100];

4
UI/Interop/DebugState.cs
View file

@ -635,6 +635,10 @@ namespace Mesen.GUI
public byte IrqEnabled; public byte IrqEnabled;
public byte InputSelect; public byte InputSelect;
public byte SerialData;
public byte SerialControl;
public byte SerialBitCount;
[MarshalAs(UnmanagedType.ByValArray, SizeConst = 0x100)] [MarshalAs(UnmanagedType.ByValArray, SizeConst = 0x100)]
public byte[] IsReadRegister; public byte[] IsReadRegister;