int Exec6502(M6502 *R,int RunCycles)
{
register pair J,K;
register byte I;
/* Execute requested number of cycles */
while(RunCycles>0)
{
#ifdef DEBUG
/* Turn tracing on when reached trap address */
if(R->PC.W==R->Trap) R->Trace=1;
/* Call single-step debugger, exit if requested */
if(R->Trace)
if(!Debug6502(R)) return(RunCycles);
#endif
I=Op6502(R->PC.W++);
RunCycles-=Cycles[I];
switch(I)
{
#include "Codes.h"
}
}
/* Return number of cycles left (<=0) */
return(RunCycles);
}
word Run6502(M6502 *R)
{
register pair J,K;
register byte I;
for(;;)
{
#ifdef S60
Opt6502(R);
#else /* !S60 */
#ifdef DEBUG
/* Turn tracing on when reached trap address */
if(R->PC.W==R->Trap) R->Trace=1;
/* Call single-step debugger, exit if requested */
if(R->Trace)
if(!Debug6502(R)) return(R->PC.W);
#endif
I=Op6502(R->PC.W++);
R->ICount-=Cycles[I];
switch(I)
{
#include "Codes.h"
}
#endif /* !S60 */
/* If cycle counter expired... */
if(R->ICount<=0)
{
/* If we have come after CLI, get INT_? from IRequest */
/* Otherwise, get it from the loop handler */
if(R->AfterCLI)
{
I=R->IRequest; /* Get pending interrupt */
R->ICount+=R->IBackup-1; /* Restore the ICount */
R->AfterCLI=0; /* Done with AfterCLI state */
}
else
{
I=Loop6502(R); /* Call the periodic handler */
R->ICount+=R->IPeriod; /* Reset the cycle counter */
if(!I) I=R->IRequest; /* Realize pending interrupt */
}
if(I==INT_QUIT) return(R->PC.W); /* Exit if INT_QUIT */
if(I) Int6502(R,I); /* Interrupt if needed */
}
}
/* Execution stopped */
return(R->PC.W);
}
/*************************************************************/
#if 0 /* -NS- */
word Exec6502(M6502 *R)
{
register pair J,K;
register byte I;
I=Op6502(R->PC.W++);
R->ICount-=Cycles[I];
switch(I)
{
#include "Codes.h"
}
/* We are done */
return(R->PC.W);
}