BizHawk/wonderswan/interrupt.cpp

96 lines
1.6 KiB
C++

#include "system.h"
//#include <trio/trio.h>
namespace MDFN_IEN_WSWAN
{
void Interrupt::Recalc()
{
IStatus |= (IAsserted & LevelTriggeredMask) & IEnable;
IOn_Cache = false;
IOn_Which = 0;
IVector_Cache = 0;
for(int i = 0; i < 8; i++)
{
if(IStatus & IEnable & (1U << i))
{
IOn_Cache = TRUE;
IOn_Which = i;
IVector_Cache = (IVectorBase + i) * 4;
break;
}
}
}
void Interrupt::AssertInterrupt(unsigned which, bool asserted)
{
const uint8 prev_IAsserted = IAsserted;
IAsserted &= ~(1U << which);
IAsserted |= (unsigned)asserted << which;
IStatus |= ((prev_IAsserted ^ IAsserted) & IAsserted) & IEnable;
Recalc();
}
void Interrupt::DoInterrupt(unsigned which)
{
IStatus |= (1U << which) & IEnable;
Recalc();
}
void Interrupt::Write(uint32 A, uint8 V)
{
//printf("Write: %04x %02x\n", A, V);
switch(A)
{
case 0xB0: IVectorBase = V; Recalc(); break;
case 0xB2: IEnable = V; IStatus &= IEnable; Recalc(); break;
case 0xB6: IStatus &= ~V; Recalc(); break;
}
}
uint8 Interrupt::Read(uint32 A)
{
//printf("Read: %04x\n", A);
switch(A)
{
case 0xB0: return(IVectorBase);
case 0xB2: return(IEnable);
case 0xB6: return(1 << IOn_Which); //return(IStatus);
}
return(0);
}
void Interrupt::Check()
{
if(IOn_Cache)
{
sys->cpu.interrupt(IVector_Cache, FALSE);
}
}
void Interrupt::Reset()
{
IAsserted = 0x00;
IEnable = 0x00;
IStatus = 0x00;
IVectorBase = 0x00;
Recalc();
}
SYNCFUNC(Interrupt)
{
NSS(IAsserted);
NSS(IStatus);
NSS(IEnable);
NSS(IVectorBase);
NSS(IOn_Cache);
NSS(IOn_Which);
NSS(IVector_Cache);
}
}