cpu.cpp

DVB-S的softcam源代码

		if (spHi>spLow && sp>spHi) {
			printf("*** stack underflow (count=%d)\n",LoopCount);
			return 1;
			}
		LoopCount++;

		bool flag=(pc>=0x80 && pc<0xE0);
		if (pc80flag && !flag && Show_Diss==1) printf("6805: [...]\n");
		pc80flag=flag;

		sprintf(displaystr1,"  %.4X: ", pc);
	    sprintf(displaystr2,"");
		sprintf(txt,"%.2X", Get(pc));	strcat(displaystr1, txt);
		if (Show_Diss==1) de(printf("6805: %02x:%04x %02x %02x %02x %02x %04x %c%c%c%c%c%c %02x%02x%02x%02x %02x%02x%02x%02x ",
				       cr,pc,a,x,y,dr,sp,
				       cc.v?'V':'.',cc.h?'H':'.',cc.i?'I':'.',cc.n?'N':'.',cc.z?'Z':'.',cc.c?'C':'.',
				       Get(pc),Get(pc+1),Get(pc+2),Get(pc+3),Get(sp+1),Get(sp+2),Get(sp+3),Get(sp+4)))

		Stepper();
		unsigned char *ex=&x;
		unsigned short idx=*ex;
		indirect=false;
		bool paged=false, vbra=false;
		unsigned char ins=Get(pc++);
		char xs='X', xi='X';
 
	  // check pre-bytes
		switch (ins) {
			case 0x31: // use SP indexed or indirect paged mode (ST19)
				ins=Get(pc++);
				switch(ins) {
					case 0x22: case 0x23: case 0x24: case 0x25: case 0x26: case 0x27: 
						vbra=true; 
						if (Show_Diss==1) printf("WARN: V-flag not yet calculated ");
						break;
					case 0x75:
					case 0x8D:
					case 0xC0: case 0xC1: case 0xC2: case 0xC3: case 0xC4: case 0xC5: case 0xC6: case 0xC7: case 0xC8: case 0xC9: case 0xCA: case 0xCB:
					case 0xCE: case 0xCF:
					case 0xD0: case 0xD1: case 0xD2: case 0xD3: case 0xD4: case 0xD5: case 0xD6: case 0xD7: case 0xD8: case 0xD9: case 0xDA: case 0xDB:
					case 0xDE: case 0xDF: 
						paged=true; 
						indirect=true; 
						break;
					case 0xE0: case 0xE1: case 0xE2: case 0xE3: case 0xE4: case 0xE5: case 0xE6: case 0xE7: case 0xE8: case 0xE9: case 0xEA: case 0xEB:
					case 0xEE: case 0xEF: 
						idx=sp; 
						de(xi='S') 
							break;
				}
				break;
			case 0x32: // use indirect SP indexed or indirect paged Y indexed mode (ST19)
				ins=Get(pc++);
				switch(ins) {
					case 0x22: case 0x23: case 0x24: case 0x25: case 0x26: case 0x27: 
						vbra=true; 
						if (Show_Diss==1) printf("WARN: V-flag not yet calculated ");
						indirect=true; 
						break;
					case 0xC3:
					case 0xCE: case 0xCF:
					case 0xD0: case 0xD1: case 0xD2: case 0xD3: case 0xD4: case 0xD5: case 0xD6: case 0xD7: case 0xD8: case 0xD9: case 0xDA: case 0xDB:
					case 0xDE: case 0xDF: 
						paged=true; 
						indirect=true; 
						ex=&y; idx=*ex; 
						de(xs='Y') 
						de(xi='Y') 
						break;
					case 0xE0: case 0xE1: case 0xE2: case 0xE3: case 0xE4: case 0xE5: case 0xE6: case 0xE7: case 0xE8: case 0xE9: case 0xEA: case 0xEB:
					case 0xEE: case 0xEF: indirect=true; idx=sp; de(xi='S') break;
				}
				break;
			case 0x91: // use Y register with indirect addr mode (ST7)
				indirect=true;
				// fall through
			case 0x90: // use Y register (ST7)
				ex=&y; idx=*ex; de(xs='Y') de(xi='Y')
				ins=Get(pc++);
				break;
			case 0x92: // use indirect addr mode (ST7)
				indirect=true;
				ins=Get(pc++);
				break;
		}

		char str[8];
		if (!vbra) _snprintf(str,sizeof(str),ops[ins],xs,xs^1);
		else       _snprintf(str,sizeof(str),"%s",vops[ins-0x22]);
		sprintf(txt,"%-5s ", str); strcat(displaystr2, txt);
		if (pc80flag && Show_Diss==1) printf(txt);

	  // address decoding
		unsigned short ea=0;
		unsigned char flags=opFlags[ins];
		unsigned char pr=(flags&4) ? dr:cr;
		switch (((flags&8) ? flags:ins)>>4) {
			case 0x2:			// no or special address mode
			case 0x8:
			case 0x9:
				if (ISlen[ins] == 2) {
					sprintf(txt,"%.2X", Get(pc)); strcat(displaystr1, txt);
				}
				break;
			case 0xA:			// immediate
				if (ISlen[ins] == 2) {
					sprintf(txt,"%.2X", Get(pc)); strcat(displaystr1, txt);
				}
				sprintf(txt,"#%02x ",Get(pc)); strcat(displaystr2, txt);
				if (pc80flag && Show_Diss==1) printf(txt);
				ea=pc++; break;
			case 0x3:			// short
			case 0xB:
				sprintf(txt,"%.2X", Get(pc)); strcat(displaystr1, txt);
				ea=Get(pc++);
				
				if (ea==5) 
					//Special Attribute bit
					ea = 5;
				else {
					if(!indirect) {		// short direct
				  }
					else {			// short indirect
					  de(printf("[%02x] -> ",ea))
					  ea=Get(ea);
					}
				}
				sprintf(txt,"%02x ",ea); strcat(displaystr2, txt);
				if (pc80flag && Show_Diss==1) printf(txt);
				break;
			case 0xC:			// long
				if(!indirect) {		// long direct
					sprintf(txt,"%.2X%.2X", Get(pc),Get(pc+1)); strcat(displaystr1, txt);
					ea=HILO(pc); pc+=2;
				} else {			// long indirect
					sprintf(txt,"%.2X", Get(pc)); strcat(displaystr1, txt);
					if (paged) {
						ea=HILO(pc); pc+=2;
						sprintf(txt,"[%s] -> ",PADDR(pr,ea)); strcat(displaystr2, txt);
						if (pc80flag && Show_Diss==1) printf(txt);
						unsigned char s=Get(pr,ea);
						ea=HILOS(pr,ea+1);
						pr=s;
				    } else {
						ea=Get(pc++);
						sprintf(txt,"[%02x] -> ",ea); strcat(displaystr2, txt);
						if (pc80flag && Show_Diss==1) printf(txt);
						ea=HILO(ea);
				    }
				}
				sprintf(txt,"%s ",PADDR(pr,ea)); strcat(displaystr2, txt);
				if (pc80flag && Show_Diss==1) printf(txt);
				break;
			case 0xD:			// long indexed
				if(!indirect) {		// long direct indexed
					sprintf(txt,"%.2X%.2X", Get(pc),Get(pc+1)); strcat(displaystr1, txt);
					ea=HILO(pc); pc+=2;
					sprintf(txt,"(%s",PADDR(cr,ea)); strcat(displaystr2, txt);
					if (pc80flag && Show_Diss==1) printf(txt);
				} else {			// long indirect indexed
					sprintf(txt,"%.2X", Get(pc)); strcat(displaystr1, txt);
					if(paged) {
						ea=HILO(pc); pc+=2;
						sprintf(txt,"([%s]",PADDR(pr,ea)); strcat(displaystr2, txt);
						if (pc80flag && Show_Diss==1) printf(txt);
						unsigned char s=Get(pr,ea++);
						ea=HILOS(pr,ea);
						pr=s;
				    } else {
						ea=Get(pc++);
						sprintf(txt,"([%02x]",ea); strcat(displaystr2, txt);
						if (pc80flag && Show_Diss==1) printf(txt);
						ea=HILO(ea);
				    }
					sprintf(txt,",%c) -> (%s",xi,PADDR(pr,ea)); strcat(displaystr2, txt);
					if (pc80flag && Show_Diss==1) printf(txt);
				}
				ea+=idx;
				sprintf(txt,",%c) -> %s ",xi,PADDR(pr,ea)); strcat(displaystr2, txt);
				if (pc80flag && Show_Diss==1) printf(txt);
				break;
			case 0x6:			// short indexed
			case 0xE:
				sprintf(txt,"%.2X", Get(pc)); strcat(displaystr1, txt);
				ea=Get(pc++);
				if(!indirect) {		// short direct indexed
					sprintf(txt,"(%02x",ea); strcat(displaystr2, txt);
					if (pc80flag && Show_Diss==1) printf(txt);
				} else {			// short indirect indexed
					sprintf(txt,"([%02x]",ea); strcat(displaystr2, txt);
					if (pc80flag && Show_Diss==1) printf(txt);
					ea=Get(ea);
					sprintf(txt,",%c) -> (%02x",xi,ea); strcat(displaystr2, txt);
					if (pc80flag && Show_Diss==1) printf(txt);
				}
				ea+=idx;
				sprintf(txt,",%c) -> %s ",xi,PADDR(pr,ea)); strcat(displaystr2, txt);
				if (pc80flag && Show_Diss==1) printf(txt);
				break;
			case 0x7:			// indexed
			case 0xF:
				ea=idx;
				sprintf(txt,"(%c) -> %s ",xi,PADDR(pr,ea)); strcat(displaystr2, txt);
				if (pc80flag && Show_Diss==1) printf(txt);
				break;
			case 0x4:			// inherent A
				sprintf(txt,"A "); strcat(displaystr2, txt);
				if (pc80flag && Show_Diss==1) printf(txt);
				break;
			case 0x5:			// inherent X/Y
				sprintf(txt,"%c ",xs); strcat(displaystr2, txt);
				if (pc80flag && Show_Diss==1) printf(txt);
				break;
			case 0x0:			// bit
			case 0x1:
				sprintf(txt,"%.2X", Get(pc)); strcat(displaystr1, txt);
				ea=Get(pc++);
				if(!indirect) {
				} else {
					sprintf(txt,"[%02x] -> ",ea); strcat(displaystr2, txt);
					if (pc80flag && Show_Diss==1) printf(txt);
					ea=Get(ea);
					indirect=false; // don't use indirect mode in case this is a bit branch
				}
				sprintf(txt,"%02x ",ea); strcat(displaystr2, txt);
				if (pc80flag && Show_Diss==1) printf(txt);
				break;
		}

		// read operant
		unsigned char op=0;
		if (flags & 1) {
			switch (((flags&8) ? flags:ins)>>4) {
				case 0x2:			// no or special address mode
				case 0x8:
				case 0x9:
				  break;
				case 0xA:			// immediate
				case 0x3:			// short
				case 0xB:
				case 0xC:			// long
				case 0xD:			// long indexed
				case 0x6:			// short indexed
				case 0xE:
				case 0x7:			// indexed
				case 0xF:
				case 0x0:			// bit
				case 0x1:
				  //if register 5 bit 7 is set
				  if (Get(0x00,0x05)& 0x40) {
					  //Get Start and end of codespace from bin
					  unsigned short start = Get(0, 0x30C0);
					  unsigned short end =  Get(0,0x30C1);
					  if ( ((ea>>8) >=start) && ((ea>>8)<=end))
						  //its in the dataspace - return 0
						  op = 0x00;
					  else
						  //its in the codespace return 1
						  op = 0x01;
				  }
				  else
					  op=Get(pr,ea); 
				  break;
				case 0x4:			// inherent A
				  op=a; break;
				case 0x5:			// inherent X/Y
				  op=*ex; break;
			}
		}

		// command decoding
#ifdef DEBUG_STAT
		stats[ins]++;
#endif
		switch (ins) {
			case 0xA6: // LDA
			case 0xB6:
			case 0xC6:
			case 0xD6:
			case 0xE6:
			case 0xF6:
				a=op; tst(op); break;
			case 0xAE: // LDX
			case 0xBE:
			case 0xCE:
			case 0xDE:
			case 0xEE:
			case 0xFE:
				*ex=op; tst(op); break;
			case 0xB7: // STA
			case 0xC7:
			case 0xD7:
			case 0xE7:
			case 0xF7:
				op=a; tst(op); break;
			case 0xBF: // STX
			case 0xCF:
			case 0xDF:
			case 0xEF:
			case 0xFF:
				op=*ex; tst(op); break;
			case 0x97: // TAX
				*ex=a; break;
			case 0x9F: // TXA
				a=*ex; break;
			case 0x93: // TYX (ST7)
				if(ex==&x) *ex=y; else *ex=x; break;
			case 0x3D: // TST
			case 0x4D:
			case 0x5D:
			case 0x6D:
			case 0x7D:
				tst(op); break;
			case 0x3F: // CLR
			case 0x4F:
			case 0x5F:
			case 0x6F:
			case 0x7F:
				op=0; tst(0); break;
			case 0x3C: // INC
			case 0x4C:
			case 0x5C:
			case 0x6C:
			case 0x7C:
				op++; tst(op); break;
			case 0x3A: // DEC
			case 0x4A:
			case 0x5A:
			case 0x6A:
			case 0x7A:
				op--; tst(op); break;
			case 0x33: // COM
			case 0x43:
			case 0x53:
			case 0x63:
			case 0x73:
				op=~op; cc.c=1; tst(op); break;
			case 0x30: // NEG
			case 0x40:
			case 0x50:
			case 0x60:
			case 0x70:
				op=~op+1; if(!op) cc.c=0; tst(op); break;
			case 0x42: // MUL
			case 0x52:
				{
				unsigned short res=*ex * a;
				*ex=(res>>8); a=res&0xff; cc.c=0; cc.h=0;
				break;
				}
			case 0xA9: // ADC
			case 0xB9:
			case 0xC9:
			case 0xD9:
			case 0xE9:
			case 0xF9:
				a=add(op,cc.c); break;
			case 0xAB: // ADD
			case 0xBB:
			case 0xCB:
			case 0xDB:
			case 0xEB:
			case 0xFB:
				a=add(op,0); break;
			case 0xA2: // SBC
			case 0xB2:
			case 0xC2:
			case 0xD2:
			case 0xE2:
			case 0xF2:
				a=sub(a,op,cc.c); break;
			case 0xA0: // SUB
			case 0xB0:
			case 0xC0:
			case 0xD0:
			case 0xE0:
			case 0xF0:
				a=sub(a,op,0); break;
			case 0xA1: // CMP
			case 0xB1:
			case 0xC1:
			case 0xD1:
			case 0xE1:
			case 0xF1:
				sub(a,op,0); break;
			case 0xA3: // CPX