m6808.c

这个是延伸mame的在wince平台下的游戏模拟器的代码

				PUSHBYTE(cc)
				SEI;
				pcreg=M_RDMEM_WORD(0xfff4);change_pc(pcreg);
				m6808_ICount -= 19;
			}
		}
}


void m6808_reset(void)
{
	pcreg = M_RDMEM_WORD(0xfffe);change_pc(pcreg);

	cc = 0x00;		/* Clear all flags */
	SEI;			/* IRQ disabled */
	areg = 0x00;	/* clear accumulator a */
	breg = 0x00;	/* clear accumulator b */
	m6808_Clear_Pending_Interrupts();

	/* default to unoptimized memory access */
	rd_s_handler = rd_slow;
	rd_s_handler_wd = rd_slow_wd;
	wr_s_handler = wr_slow;
	wr_s_handler_wd = wr_slow_wd;

	/* optimize memory access according to flags */
	if( m6808_Flags & M6808_FAST_S )
	{
		rd_s_handler=rd_fast; rd_s_handler_wd=rd_fast_wd;
		wr_s_handler=wr_fast; wr_s_handler_wd=wr_fast_wd;
	}
}


void m6808_Cause_Interrupt(int type)
{
	pending_interrupts |= type;
	if (pending_interrupts & M6808_WAI)
	{
		if ((pending_interrupts & M6808_INT_NMI) != 0)
			pending_interrupts &= ~M6808_WAI;
		else if ( (cc & 0x10) == 0 )
				pending_interrupts &= ~M6808_WAI;
	}
}


void m6808_Clear_Pending_Interrupts(void)
{
	pending_interrupts &= ~( M6808_INT_IRQ | M6808_INT_NMI | M6808_INT_OCI );
}


#include "6808ops.c"


/* execute instructions on this CPU until icount expires */
int m6808_execute(int cycles)
{
	byte ireg;
	m6808_ICount = cycles;

	if ((pending_interrupts & M6808_WAI) != 0)
	{
		m6808_ICount = 0;
		goto getout;
	}

	do
	{
		if (pending_interrupts != 0)
			Interrupt();

		ireg=M_RDOP(pcreg++);

		switch( ireg )
		{
			case 0x00: illegal(); break;
			case 0x01: nop(); break;
			case 0x02: illegal(); break;
			case 0x03: illegal(); break;
			case 0x04: lsrd(); /* 6803 only */; break;
			case 0x05: asld(); /* 6803 only */; break;
			case 0x06: tap(); break;
			case 0x07: tpa(); break;
			case 0x08: inx(); break;
			case 0x09: dex(); break;
			case 0x0A: CLV; break;
			case 0x0B: SEV; break;
			case 0x0C: CLC; break;
			case 0x0D: SEC; break;
			case 0x0E: CLI; break;
			case 0x0F: SEI; break;
			case 0x10: sba(); break;
			case 0x11: cba(); break;
			case 0x12: illegal(); break;
			case 0x13: illegal(); break;
			case 0x14: illegal(); break;
			case 0x15: illegal(); break;
			case 0x16: tab(); break;
			case 0x17: tba(); break;
			case 0x18: xgdx(); /* HD63701YO only */; break;
			case 0x19: daa(); break;
			case 0x1a: illegal(); break;
			case 0x1b: aba(); break;
			case 0x1c: illegal(); break;
			case 0x1d: illegal(); break;
			case 0x1e: illegal(); break;
			case 0x1f: illegal(); break;
			case 0x20: bra(); break;
			case 0x21: brn(); break;
			case 0x22: bhi(); break;
			case 0x23: bls(); break;
			case 0x24: bcc(); break;
			case 0x25: bcs(); break;
			case 0x26: bne(); break;
			case 0x27: beq(); break;
			case 0x28: bvc(); break;
			case 0x29: bvs(); break;
			case 0x2a: bpl(); break;
			case 0x2b: bmi(); break;
			case 0x2c: bge(); break;
			case 0x2d: blt(); break;
			case 0x2e: bgt(); break;
			case 0x2f: ble(); break;
			case 0x30: tsx(); break;
			case 0x31: ins(); break;
			case 0x32: pula(); break;
			case 0x33: pulb(); break;
			case 0x34: des(); break;
			case 0x35: txs(); break;
			case 0x36: psha(); break;
			case 0x37: pshb(); break;
			case 0x38: pulx(); /* 6803 only */ break;
			case 0x39: rts(); break;
			case 0x3a: abx(); /* 6803 only */ break;
			case 0x3b: rti(); break;
			case 0x3c: pshx(); /* 6803 only */ break;
			case 0x3d: mul(); /* 6803 only */ break;
			case 0x3e: wai(); break;
			case 0x3f: swi(); break;
			case 0x40: nega(); break;
			case 0x41: illegal(); break;
			case 0x42: illegal(); break;
			case 0x43: coma(); break;
			case 0x44: lsra(); break;
			case 0x45: illegal(); break;
			case 0x46: rora(); break;
			case 0x47: asra(); break;
			case 0x48: asla(); break;
			case 0x49: rola(); break;
			case 0x4a: deca(); break;
			case 0x4b: illegal(); break;
			case 0x4c: inca(); break;
			case 0x4d: tsta(); break;
			case 0x4e: illegal(); break;
			case 0x4f: clra(); break;
			case 0x50: negb(); break;
			case 0x51: illegal(); break;
			case 0x52: illegal(); break;
			case 0x53: comb(); break;
			case 0x54: lsrb(); break;
			case 0x55: illegal(); break;
			case 0x56: rorb(); break;
			case 0x57: asrb(); break;
			case 0x58: aslb(); break;
			case 0x59: rolb(); break;
			case 0x5a: decb(); break;
			case 0x5b: illegal(); break;
			case 0x5c: incb(); break;
			case 0x5d: tstb(); break;
			case 0x5e: illegal(); break;
			case 0x5f: clrb(); break;
			case 0x60: neg_ix(); break;
			case 0x61: aim_ix(); /* HD63701YO only */; break;
			case 0x62: oim_ix(); /* HD63701YO only */; break;
			case 0x63: com_ix(); break;
			case 0x64: lsr_ix(); break;
			case 0x65: eim_ix(); /* HD63701YO only */; break;
			case 0x66: ror_ix(); break;
			case 0x67: asr_ix(); break;
			case 0x68: asl_ix(); break;
			case 0x69: rol_ix(); break;
			case 0x6a: dec_ix(); break;
			case 0x6b: tim_ix(); /* HD63701YO only */; break;
			case 0x6c: inc_ix(); break;
			case 0x6d: tst_ix(); break;
			case 0x6e: jmp_ix(); break;
			case 0x6f: clr_ix(); break;
			case 0x70: neg_ex(); break;
			case 0x71: aim_di(); /* HD63701YO only */; break;
			case 0x72: oim_di(); /* HD63701YO only */; break;
			case 0x73: com_ex(); break;
			case 0x74: lsr_ex(); break;
			case 0x75: eim_di(); /* HD63701YO only */; break;
			case 0x76: ror_ex(); break;
			case 0x77: asr_ex(); break;
			case 0x78: asl_ex(); break;
			case 0x79: rol_ex(); break;
			case 0x7a: dec_ex(); break;
			case 0x7b: tim_di(); /* HD63701YO only */; break;
			case 0x7c: inc_ex(); break;
			case 0x7d: tst_ex(); break;
			case 0x7e: jmp_ex(); break;
			case 0x7f: clr_ex(); break;
			case 0x80: suba_im(); break;
			case 0x81: cmpa_im(); break;
			case 0x82: sbca_im(); break;
			case 0x83: subd_im(); /* 6803 only */ break;
			case 0x84: anda_im(); break;
			case 0x85: bita_im(); break;
			case 0x86: lda_im(); break;
			case 0x87: sta_im(); break;
			case 0x88: eora_im(); break;
			case 0x89: adca_im(); break;
			case 0x8a: ora_im(); break;
			case 0x8b: adda_im(); break;
			case 0x8c: cmpx_im(); break;
			case 0x8d: bsr(); break;
			case 0x8e: lds_im(); break;
			case 0x8f: sts_im(); /* orthogonality */ break;
			case 0x90: suba_di(); break;
			case 0x91: cmpa_di(); break;
			case 0x92: sbca_di(); break;
			case 0x93: subd_di(); /* 6803 only */ break;
			case 0x94: anda_di(); break;
			case 0x95: bita_di(); break;
			case 0x96: lda_di(); break;
			case 0x97: sta_di(); break;
			case 0x98: eora_di(); break;
			case 0x99: adca_di(); break;
			case 0x9a: ora_di(); break;
			case 0x9b: adda_di(); break;
			case 0x9c: cmpx_di(); break;
			case 0x9d: jsr_di(); break;
			case 0x9e: lds_di(); break;
			case 0x9f: sts_di(); break;
			case 0xa0: suba_ix(); break;
			case 0xa1: cmpa_ix(); break;
			case 0xa2: sbca_ix(); break;
			case 0xa3: subd_ix(); /* 6803 only */ break;
			case 0xa4: anda_ix(); break;
			case 0xa5: bita_ix(); break;
			case 0xa6: lda_ix(); break;
			case 0xa7: sta_ix(); break;
			case 0xa8: eora_ix(); break;
			case 0xa9: adca_ix(); break;
			case 0xaa: ora_ix(); break;
			case 0xab: adda_ix(); break;
			case 0xac: cmpx_ix(); break;
			case 0xad: jsr_ix(); break;
			case 0xae: lds_ix(); break;
			case 0xaf: sts_ix(); break;
			case 0xb0: suba_ex(); break;
			case 0xb1: cmpa_ex(); break;
			case 0xb2: sbca_ex(); break;
			case 0xb3: subd_ex(); /* 6803 only */ break;
			case 0xb4: anda_ex(); break;
			case 0xb5: bita_ex(); break;
			case 0xb6: lda_ex(); break;
			case 0xb7: sta_ex(); break;
			case 0xb8: eora_ex(); break;
			case 0xb9: adca_ex(); break;
			case 0xba: ora_ex(); break;
			case 0xbb: adda_ex(); break;
			case 0xbc: cmpx_ex(); break;
			case 0xbd: jsr_ex(); break;
			case 0xbe: lds_ex(); break;
			case 0xbf: sts_ex(); break;
			case 0xc0: subb_im(); break;
			case 0xc1: cmpb_im(); break;
			case 0xc2: sbcb_im(); break;
			case 0xc3: addd_im(); /* 6803 only */ break;
			case 0xc4: andb_im(); break;
			case 0xc5: bitb_im(); break;
			case 0xc6: ldb_im(); break;
			case 0xc7: stb_im(); break;
			case 0xc8: eorb_im(); break;
			case 0xc9: adcb_im(); break;
			case 0xca: orb_im(); break;
			case 0xcb: addb_im(); break;
			case 0xcc: ldd_im(); /* 6803 only */ break;
			case 0xcd: std_im(); /* 6803 only -- orthogonality */ break;
			case 0xce: ldx_im(); break;
			case 0xcf: stx_im(); break;
			case 0xd0: subb_di(); break;
			case 0xd1: cmpb_di(); break;
			case 0xd2: sbcb_di(); break;
			case 0xd3: addd_di(); /* 6803 only */ break;
			case 0xd4: andb_di(); break;
			case 0xd5: bitb_di(); break;
			case 0xd6: ldb_di(); break;
			case 0xd7: stb_di(); break;
			case 0xd8: eorb_di(); break;
			case 0xd9: adcb_di(); break;
			case 0xda: orb_di(); break;
			case 0xdb: addb_di(); break;
			case 0xdc: ldd_di(); /* 6803 only */ break;
			case 0xdd: std_di(); /* 6803 only */ break;
			case 0xde: ldx_di(); break;
			case 0xdf: stx_di(); break;
			case 0xe0: subb_ix(); break;
			case 0xe1: cmpb_ix(); break;
			case 0xe2: sbcb_ix(); break;
			case 0xe3: addd_ix(); /* 6803 only */ break;
			case 0xe4: andb_ix(); break;
			case 0xe5: bitb_ix(); break;
			case 0xe6: ldb_ix(); break;
			case 0xe7: stb_ix(); break;
			case 0xe8: eorb_ix(); break;
			case 0xe9: adcb_ix(); break;
			case 0xea: orb_ix(); break;
			case 0xeb: addb_ix(); break;
			case 0xec: ldd_ix(); /* 6803 only */ break;
			case 0xed: std_ix(); /* 6803 only */ break;
			case 0xee: ldx_ix(); break;
			case 0xef: stx_ix(); break;
			case 0xf0: subb_ex(); break;
			case 0xf1: cmpb_ex(); break;
			case 0xf2: sbcb_ex(); break;
			case 0xf3: addd_ex(); /* 6803 only */ break;
			case 0xf4: andb_ex(); break;
			case 0xf5: bitb_ex(); break;
			case 0xf6: ldb_ex(); break;
			case 0xf7: stb_ex(); break;
			case 0xf8: eorb_ex(); break;
			case 0xf9: adcb_ex(); break;
			case 0xfa: orb_ex(); break;
			case 0xfb: addb_ex(); break;
			case 0xfc: ldd_ex(); /* 6803 only */ break;
			case 0xfd: std_ex(); /* 6803 only */ break;
			case 0xfe: ldx_ex(); break;
			case 0xff: stx_ex(); break;
		}
		m6808_ICount -= cycles1[ireg];
	} while( m6808_ICount>0 );

getout:
	return cycles - m6808_ICount;
}