void cpuSetUpInterrupt(ULO new_interrupt_level)
{
UWO vector_offset = (UWO) (0x60 + new_interrupt_level*4);
ULO vector_address = memoryReadLong(cpuGetVbr() + vector_offset);
cpuActivateSSP(); // Switch to using ssp or msp. Loads a7 and preserves usp if we came from user-mode.
cpuStackFrameGenerate(vector_offset, cpuGetPC()); // This will end up on msp if master is enabled, or on the ssp/isp if not.
cpuSetSR(cpuGetSR() & 0x38ff); // Clear interrupt level
cpuSetSR(cpuGetSR() | 0x2000); // Set supervisor mode
cpuSetSR(cpuGetSR() | (UWO)(new_interrupt_level << 8)); // Set interrupt level
#ifdef CPU_INSTRUCTION_LOGGING
cpuCallInterruptLoggingFunc(new_interrupt_level, vector_address);
#endif
if (cpuGetModelMajor() >= 2 && cpuGetModelMajor() < 6)
{
if (cpuGetFlagMaster())
{ // If the cpu was in master mode, preserve msp, and switch to using ssp (isp) in a7.
ULO oldA7 = cpuGetAReg(7);
cpuSetMspDirect(oldA7);
cpuSetAReg(7, cpuGetSspDirect());
cpuFrame1(vector_offset, cpuGetPC()); // Make the throwaway frame on ssp/isp
cpuSetSR(cpuGetSR() & 0xefff); // Clear master bit
}
}
cpuInitializeFromNewPC(vector_address);
cpuSetStop(FALSE);
cpuSetRaiseInterrupt(FALSE);
}
void cpuThrowException(ULO vector_offset, ULO pc, BOOLE executejmp)
{
ULO vector_address;
#ifdef CPU_INSTRUCTION_LOGGING
cpuCallExceptionLoggingFunc(cpuGetExceptionName(vector_offset), cpuGetOriginalPC(), cpuGetCurrentOpcode());
#endif
cpuActivateSSP();
cpuStackFrameGenerate((UWO) vector_offset, pc);
// read a memory position
vector_address = memoryReadLong(cpuGetVbr() + vector_offset);
if (cpuGetModelMajor() < 2 && vector_address & 0x1 && vector_offset == 0xc)
{
// Avoid endless loop that will crash the emulator.
// The (odd) address error exception vector contained an odd address.
cpuCallResetExceptionFunc();
cpuHardReset();
cpuSetInstructionTime(132);
}
else
{
// set supervisor modus
cpuSetSR(cpuGetSR() | 0x2000);
cpuSetSR(cpuGetSR() & 0x3fff);
// restart cpu, if needed
cpuSetStop(FALSE);
cpuInitializeFromNewPC(vector_address);
cpuSetInstructionTime(40);
}
// If the exception happened mid-instruction...
if (executejmp)
{
cpuCallMidInstructionExceptionFunc(); // Supposed to be doing setjmp/longjmp back to machine emulator code
}
}