Mesen2/Core/WS/WsTimer.cpp
2024-09-19 21:19:43 +09:00

98 lines
2.4 KiB
C++

#include "pch.h"
#include "WS/WsTimer.h"
#include "WS/WsMemoryManager.h"
#include "Utilities/BitUtilities.h"
void WsTimer::Init(WsMemoryManager* memoryManager)
{
_memoryManager = memoryManager;
}
void WsTimer::TickHorizontalTimer()
{
if(_state.HTimer == 1) {
_memoryManager->SetIrqSource(WsIrqSource::HorizontalBlankTimer);
}
if(_state.HBlankEnabled) {
if(_state.HTimer && !--_state.HTimer && _state.HBlankAutoReload) {
_state.HTimer = _state.HReloadValue;
}
}
}
void WsTimer::TickVerticalTimer()
{
if(_state.VTimer == 1) {
_memoryManager->SetIrqSource(WsIrqSource::VerticalBlankTimer);
}
if(_state.VBlankEnabled) {
if(_state.VTimer && !--_state.VTimer && _state.VBlankAutoReload) {
_state.VTimer = _state.VReloadValue;
}
}
}
uint8_t WsTimer::ReadPort(uint16_t port)
{
switch(port) {
case 0xA2: return _state.Control;
case 0xA4: return BitUtilities::GetBits<0>(_state.HReloadValue); break;
case 0xA5: return BitUtilities::GetBits<8>(_state.HReloadValue); break;
case 0xA6: return BitUtilities::GetBits<0>(_state.VReloadValue); break;
case 0xA7: return BitUtilities::GetBits<8>(_state.VReloadValue); break;
case 0xA8: return BitUtilities::GetBits<0>(_state.HTimer); break;
case 0xA9: return BitUtilities::GetBits<8>(_state.HTimer); break;
case 0xAA: return BitUtilities::GetBits<0>(_state.VTimer); break;
case 0xAB: return BitUtilities::GetBits<8>(_state.VTimer); break;
}
return 0;
}
void WsTimer::WritePort(uint16_t port, uint8_t value)
{
switch(port) {
case 0xA2:
_state.Control = value & 0x0F;
_state.HBlankEnabled = value & 0x01;
_state.HBlankAutoReload = value & 0x02;
_state.VBlankEnabled = value & 0x04;
_state.VBlankAutoReload = value & 0x08;
break;
case 0xA4:
BitUtilities::SetBits<0>(_state.HReloadValue, value);
_state.HTimer = _state.HReloadValue;
break;
case 0xA5:
BitUtilities::SetBits<8>(_state.HReloadValue, value);
_state.HTimer = _state.HReloadValue;
break;
case 0xA6:
BitUtilities::SetBits<0>(_state.VReloadValue, value);
_state.VTimer = _state.VReloadValue;
break;
case 0xA7:
BitUtilities::SetBits<8>(_state.VReloadValue, value);
_state.VTimer = _state.VReloadValue;
break;
}
}
void WsTimer::Serialize(Serializer& s)
{
SV(_state.HTimer);
SV(_state.VTimer);
SV(_state.HReloadValue);
SV(_state.VReloadValue);
SV(_state.Control);
SV(_state.HBlankEnabled);
SV(_state.HBlankAutoReload);
SV(_state.VBlankEnabled);
SV(_state.VBlankAutoReload);
}