u8 Processor::Tick()
{
m_iCurrentClockCycles = 0;
if (m_bHalt)
{
m_iCurrentClockCycles += (m_bCGBSpeed ? 2 : 4);
if (m_iUnhaltCycles > 0)
{
m_iUnhaltCycles -= m_iCurrentClockCycles;
if (m_iUnhaltCycles <= 0)
{
m_iUnhaltCycles = 0;
m_bHalt = false;
}
}
if (m_bHalt && (InterruptPending() != None_Interrupt) && (m_iUnhaltCycles == 0))
{
m_iUnhaltCycles = (m_bCGBSpeed ? 6 : 12);
}
}
if (!m_bHalt)
{
ServeInterrupt(InterruptPending());
ExecuteOPCode(FetchOPCode());
}
UpdateDelayedInterrupts();
UpdateTimers();
UpdateSerial();
if (m_iIMECycles > 0)
{
m_iIMECycles -= m_iCurrentClockCycles;
if (m_iIMECycles <= 0)
{
m_iIMECycles = 0;
m_bIME = true;
}
}
return m_iCurrentClockCycles;
}
u8 Processor::Tick()
{
m_iCurrentClockCycles = 0;
if (m_iAccurateOPCodeState == 0 && m_bHalt)
{
m_iCurrentClockCycles += AdjustedCycles(4);
if (m_iUnhaltCycles > 0)
{
m_iUnhaltCycles -= m_iCurrentClockCycles;
if (m_iUnhaltCycles <= 0)
{
m_iUnhaltCycles = 0;
m_bHalt = false;
}
}
if (m_bHalt && (InterruptPending() != None_Interrupt) && (m_iUnhaltCycles == 0))
{
m_iUnhaltCycles = AdjustedCycles(12);
}
}
if (!m_bHalt)
{
if (m_iAccurateOPCodeState == 0)
ServeInterrupt(InterruptPending());
if (m_bDuringBootROM)
{
u16 pc_before = PC.GetValue();
ExecuteOPCode(FetchOPCode());
u16 pc_after = PC.GetValue();
if ((pc_before == 0xFE) && (pc_after == 0x100))
{
m_bEndOfBootROM = true;
}
}
else
ExecuteOPCode(FetchOPCode());
}
UpdateDelayedInterrupts();
UpdateTimers();
UpdateSerial();
if (m_iAccurateOPCodeState == 0 && m_iIMECycles > 0)
{
m_iIMECycles -= m_iCurrentClockCycles;
if (m_iIMECycles <= 0)
{
m_iIMECycles = 0;
m_bIME = true;
}
}
return m_iCurrentClockCycles;
}