| 1 |
/** M6502: portable 6502 emulator ****************************/ |
| 2 |
/** **/ |
| 3 |
/** Debug.c **/ |
| 4 |
/** **/ |
| 5 |
/** This file contains the built-in debugging routine for **/ |
| 6 |
/** the 6502 emulator which is called on each 6502 step **/ |
| 7 |
/** when Trap!=0. Some NES-dependent features are also **/ |
| 8 |
/** included under #ifdef INES. **/ |
| 9 |
/** **/ |
| 10 |
/** Copyright (C) Marat Fayzullin 1996-2007 **/ |
| 11 |
/** You are not allowed to distribute this software **/ |
| 12 |
/** commercially. Please, notify me, if you make any **/ |
| 13 |
/** changes to this file. **/ |
| 14 |
/*************************************************************/ |
| 15 |
#ifdef DEBUG |
| 16 |
|
| 17 |
#include <stdio.h> |
| 18 |
#include <string.h> |
| 19 |
#include <ctype.h> |
| 20 |
|
| 21 |
#ifdef INES |
| 22 |
#include "NES.h" |
| 23 |
extern word VAddr; |
| 24 |
extern byte CURLINE; |
| 25 |
#endif |
| 26 |
|
| 27 |
#define RDWORD(A) (Rd6502(A+1)*256+Rd6502(A)) |
| 28 |
|
| 29 |
enum AddressingModes { Ac=0,Il,Im,Ab,Zp,Zx,Zy,Ax,Ay,Rl,Ix,Iy,In,No }; |
| 30 |
|
| 31 |
static const byte *Ops[]= |
| 32 |
{ |
| 33 |
"adc","and","asl","bcc","bcs","beq","bit","bmi", |
| 34 |
"bne","bpl","brk","bvc","bvs","clc","cld","cli", |
| 35 |
"clv","cmp","cpx","cpy","dec","dex","dey","inx", |
| 36 |
"iny","eor","inc","jmp","jsr","lda","nop","ldx", |
| 37 |
"ldy","lsr","ora","pha","php","pla","plp","rol", |
| 38 |
"ror","rti","rts","sbc","sta","stx","sty","sec", |
| 39 |
"sed","sei","tax","tay","txa","tya","tsx","txs" |
| 40 |
}; |
| 41 |
|
| 42 |
static const byte Ads[512]= |
| 43 |
{ |
| 44 |
10,Il, 34,Ix, No,No, No,No, No,No, 34,Zp, 2,Zp, No,No, |
| 45 |
36,Il, 34,Im, 2,Ac, No,No, No,No, 34,Ab, 2,Ab, No,No, |
| 46 |
9,Rl, 34,Iy, No,No, No,No, No,No, 34,Zx, 2,Zx, No,No, |
| 47 |
13,Il, 34,Ay, No,No, No,No, No,No, 34,Ax, 2,Ax, No,No, |
| 48 |
28,Ab, 1,Ix, No,No, No,No, 6,Zp, 1,Zp, 39,Zp, No,No, |
| 49 |
38,Il, 1,Im, 39,Ac, No,No, 6,Ab, 1,Ab, 39,Ab, No,No, |
| 50 |
7,Rl, 1,Iy, No,No, No,No, No,No, 1,Zx, 39,Zx, No,No, |
| 51 |
47,Il, 1,Ay, No,No, No,No, No,No, 1,Ax, 39,Ax, No,No, |
| 52 |
41,Il, 25,Ix, No,No, No,No, No,No, 25,Zp, 33,Zp, No,No, |
| 53 |
35,Il, 25,Im, 33,Ac, No,No, 27,Ab, 25,Ab, 33,Ab, No,No, |
| 54 |
11,Rl, 25,Iy, No,No, No,No, No,No, 25,Zx, 33,Zx, No,No, |
| 55 |
15,Il, 25,Ay, No,No, No,No, No,No, 25,Ax, 33,Ax, No,No, |
| 56 |
42,Il, 0,Ix, No,No, No,No, No,No, 0,Zp, 40,Zp, No,No, |
| 57 |
37,Il, 0,Im, 40,Ac, No,No, 27,In, 0,Ab, 40,Ab, No,No, |
| 58 |
12,Rl, 0,Iy, No,No, No,No, No,No, 0,Zx, 40,Zx, No,No, |
| 59 |
49,Il, 0,Ay, No,No, No,No, No,No, 0,Ax, 40,Ax, No,No, |
| 60 |
No,No, 44,Ix, No,No, No,No, 46,Zp, 44,Zp, 45,Zp, No,No, |
| 61 |
22,Il, No,No, 52,Il, No,No, 46,Ab, 44,Ab, 45,Ab, No,No, |
| 62 |
3,Rl, 44,Iy, No,No, No,No, 46,Zx, 44,Zx, 45,Zy, No,No, |
| 63 |
53,Il, 44,Ay, 55,Il, No,No, No,No, 44,Ax, No,No, No,No, |
| 64 |
32,Im, 29,Ix, 31,Im, No,No, 32,Zp, 29,Zp, 31,Zp, No,No, |
| 65 |
51,Il, 29,Im, 50,Il, No,No, 32,Ab, 29,Ab, 31,Ab, No,No, |
| 66 |
4,Rl, 29,Iy, No,No, No,No, 32,Zx, 29,Zx, 31,Zy, No,No, |
| 67 |
16,Il, 29,Ay, 54,Il, No,No, 32,Ax, 29,Ax, 31,Ay, No,No, |
| 68 |
19,Im, 17,Ix, No,No, No,No, 19,Zp, 17,Zp, 20,Zp, No,No, |
| 69 |
24,Il, 17,Im, 21,Il, No,No, 19,Ab, 17,Ab, 20,Ab, No,No, |
| 70 |
8,Rl, 17,Iy, No,No, No,No, No,No, 17,Zx, 20,Zx, No,No, |
| 71 |
14,Il, 17,Ay, No,No, No,No, No,No, 17,Ax, 20,Ax, No,No, |
| 72 |
18,Im, 43,Ix, No,No, No,No, 18,Zp, 43,Zp, 26,Zp, No,No, |
| 73 |
23,Il, 43,Im, 30,Il, No,No, 18,Ab, 43,Ab, 26,Ab, No,No, |
| 74 |
5,Rl, 43,Iy, No,No, No,No, No,No, 43,Zx, 26,Zx, No,No, |
| 75 |
48,Il, 43,Ay, No,No, No,No, No,No, 43,Ax, 26,Ax, No,No |
| 76 |
}; |
| 77 |
|
| 78 |
/** DAsm() ****************************************************/ |
| 79 |
/** This function will disassemble a single command and **/ |
| 80 |
/** return the number of bytes disassembled. **/ |
| 81 |
/**************************************************************/ |
| 82 |
static int DAsm(char *S,word A) |
| 83 |
{ |
| 84 |
byte J; |
| 85 |
word B,OP,TO; |
| 86 |
|
| 87 |
B=A;OP=Rd6502(B++)*2; |
| 88 |
|
| 89 |
switch(Ads[OP+1]) |
| 90 |
{ |
| 91 |
case Ac: sprintf(S,"%s a",Ops[Ads[OP]]);break; |
| 92 |
case Il: sprintf(S,"%s",Ops[Ads[OP]]);break; |
| 93 |
|
| 94 |
case Rl: J=Rd6502(B++);TO=A+2+((J<0x80)? J:(J-256)); |
| 95 |
sprintf(S,"%s $%04X",Ops[Ads[OP]],TO);break; |
| 96 |
|
| 97 |
case Im: sprintf(S,"%s #$%02X",Ops[Ads[OP]],Rd6502(B++));break; |
| 98 |
case Zp: sprintf(S,"%s $%02X",Ops[Ads[OP]],Rd6502(B++));break; |
| 99 |
case Zx: sprintf(S,"%s $%02X,x",Ops[Ads[OP]],Rd6502(B++));break; |
| 100 |
case Zy: sprintf(S,"%s $%02X,y",Ops[Ads[OP]],Rd6502(B++));break; |
| 101 |
case Ix: sprintf(S,"%s ($%02X,x)",Ops[Ads[OP]],Rd6502(B++));break; |
| 102 |
case Iy: sprintf(S,"%s ($%02X),y",Ops[Ads[OP]],Rd6502(B++));break; |
| 103 |
|
| 104 |
case Ab: sprintf(S,"%s $%04X",Ops[Ads[OP]],RDWORD(B));B+=2;break; |
| 105 |
case Ax: sprintf(S,"%s $%04X,x",Ops[Ads[OP]],RDWORD(B));B+=2;break; |
| 106 |
case Ay: sprintf(S,"%s $%04X,y",Ops[Ads[OP]],RDWORD(B));B+=2;break; |
| 107 |
case In: sprintf(S,"%s ($%04X)",Ops[Ads[OP]],RDWORD(B));B+=2;break; |
| 108 |
|
| 109 |
default: sprintf(S,".db $%02X",OP/2); |
| 110 |
} |
| 111 |
return(B-A); |
| 112 |
} |
| 113 |
|
| 114 |
/** Debug6502() **********************************************/ |
| 115 |
/** This function should exist if DEBUG is #defined. When **/ |
| 116 |
/** Trace!=0, it is called after each command executed by **/ |
| 117 |
/** the CPU, and given the 6502 registers. Emulation exits **/ |
| 118 |
/** if Debug6502() returns 0. **/ |
| 119 |
/*************************************************************/ |
| 120 |
byte Debug6502(M6502 *R) |
| 121 |
{ |
| 122 |
static char FA[9]="NVRBDIZC"; |
| 123 |
char S[128]; |
| 124 |
byte *P,F; |
| 125 |
int J,I,K; |
| 126 |
|
| 127 |
DAsm(S,R->PC.W); |
| 128 |
|
| 129 |
printf |
| 130 |
( |
| 131 |
"A:%02X P:%02X X:%02X Y:%02X S:%04X PC:%04X Flags:[", |
| 132 |
R->A,R->P,R->X,R->Y,R->S+0x0100,R->PC.W |
| 133 |
); |
| 134 |
|
| 135 |
for(J=0,F=R->P;J<8;J++,F<<=1) |
| 136 |
printf("%c",F&0x80? FA[J]:'.'); |
| 137 |
printf("]\n"); |
| 138 |
|
| 139 |
printf |
| 140 |
( |
| 141 |
"AT PC: [%02X - %s] AT SP: [%02X %02X %02X]\n", |
| 142 |
Rd6502(R->PC.W),S, |
| 143 |
Rd6502(0x0100+(byte)(R->S+1)), |
| 144 |
Rd6502(0x0100+(byte)(R->S+2)), |
| 145 |
Rd6502(0x0100+(byte)(R->S+3)) |
| 146 |
); |
| 147 |
|
| 148 |
while(1) |
| 149 |
{ |
| 150 |
printf("\n[Command,'?']-> "); |
| 151 |
fflush(stdout);fflush(stdin); |
| 152 |
|
| 153 |
fgets(S,50,stdin); |
| 154 |
for(J=0;S[J]>=' ';J++) |
| 155 |
S[J]=toupper(S[J]); |
| 156 |
S[J]='\0'; |
| 157 |
|
| 158 |
switch(S[0]) |
| 159 |
{ |
| 160 |
case 'H': |
| 161 |
case '?': |
| 162 |
printf("\n***** Built-in 6502 Debugger Commands *****\n"); |
| 163 |
printf("<CR> : Break at the next instruction\n"); |
| 164 |
printf("= <addr> : Break at addr\n"); |
| 165 |
printf("+ <offset> : Break at PC + offset\n"); |
| 166 |
printf("c : Continue without break\n"); |
| 167 |
printf("j <addr> : Continue from addr\n"); |
| 168 |
printf("m <addr> : Memory dump at addr\n"); |
| 169 |
printf("d <addr> : Disassembly at addr\n"); |
| 170 |
printf("v : Show interrupt vectors\n"); |
| 171 |
#ifdef INES |
| 172 |
printf("p : Show NES palette\n"); |
| 173 |
printf("r : Show NES hardware registers\n"); |
| 174 |
printf("s : Show sprite attributes\n"); |
| 175 |
printf("s <number> : Show sprite pattern\n"); |
| 176 |
#endif /* INES */ |
| 177 |
printf("?,h : Show this help text\n"); |
| 178 |
printf("q : Exit emulation\n"); |
| 179 |
break; |
| 180 |
|
| 181 |
case '\0': return(1); |
| 182 |
case '=': if(strlen(S)>=2) |
| 183 |
{ sscanf(S+1,"%hX",&(R->Trap));R->Trace=0;return(1); } |
| 184 |
break; |
| 185 |
case '+': if(strlen(S)>=2) |
| 186 |
{ |
| 187 |
sscanf(S+1,"%hX",&(R->Trap)); |
| 188 |
R->Trap+=R->PC.W;R->Trace=0; |
| 189 |
return(1); |
| 190 |
} |
| 191 |
break; |
| 192 |
case 'J': if(strlen(S)>=2) |
| 193 |
{ sscanf(S+1,"%hX",&(R->PC.W));R->Trace=0;return(1); } |
| 194 |
break; |
| 195 |
case 'C': R->Trap=0xFFFF;R->Trace=0;return(1); |
| 196 |
case 'Q': return(0); |
| 197 |
|
| 198 |
case 'V': |
| 199 |
printf("\n6502 Interrupt Vectors:\n"); |
| 200 |
printf("[$FFFC] INIT: $%04X\n",Rd6502(0xFFFC)+256*Rd6502(0xFFFD)); |
| 201 |
printf("[$FFFE] IRQ: $%04X\n",Rd6502(0xFFFE)+256*Rd6502(0xFFFF)); |
| 202 |
printf("[$FFFA] NMI: $%04X\n",Rd6502(0xFFFA)+256*Rd6502(0xFFFB)); |
| 203 |
break; |
| 204 |
|
| 205 |
case 'M': |
| 206 |
{ |
| 207 |
word Addr; |
| 208 |
|
| 209 |
if(sscanf(S+1,"%hX",&Addr)!=1) Addr=R->PC.W; |
| 210 |
printf("\n"); |
| 211 |
for(J=0;J<16;J++) |
| 212 |
{ |
| 213 |
printf("%04X: ",Addr); |
| 214 |
for(I=0;I<16;I++,Addr++) |
| 215 |
printf("%02X ",Rd6502(Addr)); |
| 216 |
printf(" | ");Addr-=16; |
| 217 |
for(I=0;I<16;I++,Addr++) |
| 218 |
printf("%c",isprint(Rd6502(Addr))? Rd6502(Addr):'.'); |
| 219 |
printf("\n"); |
| 220 |
} |
| 221 |
} |
| 222 |
break; |
| 223 |
|
| 224 |
case 'D': |
| 225 |
{ |
| 226 |
word Addr; |
| 227 |
|
| 228 |
if(sscanf(S+1,"%hX",&Addr)!=1) Addr=R->PC.W; |
| 229 |
printf("\n"); |
| 230 |
for(J=0;J<16;J++) |
| 231 |
{ |
| 232 |
printf("%04X: ",Addr); |
| 233 |
Addr+=DAsm(S,Addr); |
| 234 |
printf("%s\n",S); |
| 235 |
} |
| 236 |
} |
| 237 |
break; |
| 238 |
|
| 239 |
#ifdef INES |
| 240 |
case 'P': |
| 241 |
printf("\nNo | Picture | Sprites\n"); |
| 242 |
for(J=0;J<16;J++) |
| 243 |
{ |
| 244 |
byte B1,B2; |
| 245 |
B1=*(VRAM+0x3F00+J);B2=*(VRAM+0x3F10+J); |
| 246 |
printf |
| 247 |
( |
| 248 |
"%2d | %02X (%02X,%02X,%02X) | %02X (%02X,%02X,%02X)\n",J, |
| 249 |
B1,Palette[B1][0],Palette[B1][1],Palette[B1][2], |
| 250 |
B2,Palette[B2][0],Palette[B2][1],Palette[B2][2] |
| 251 |
); |
| 252 |
} |
| 253 |
break; |
| 254 |
|
| 255 |
case 'R': |
| 256 |
printf |
| 257 |
( |
| 258 |
"\n[$2000] PPUCONT1 = $%02X\n[$2001] PPUCONT2 = $%02X\n[$2002] PPUSTAT = $%02X\n", |
| 259 |
PPU[0],PPU[1],PPU[2] |
| 260 |
); |
| 261 |
printf |
| 262 |
( |
| 263 |
"POSITION = %d,%d\nVADDR = $%04X\nSCANLINE = %d\n", |
| 264 |
SCROLLX,SCROLLY,VAddr,CURLINE |
| 265 |
); |
| 266 |
break; |
| 267 |
|
| 268 |
case 'S': |
| 269 |
if(sscanf(S+1,"%d",&J)==1) |
| 270 |
{ |
| 271 |
K=SRAM[J*4+1]; |
| 272 |
P=SPRITES16? |
| 273 |
VPage[(K&0x01? 4:0)+(K>>6)]+((K&0x3E)<<4) |
| 274 |
:SprGen[K>>6]+((K&0x3F)<<4); |
| 275 |
printf("Sprite #%d (pattern $%02X)\n--------\n",J,K); |
| 276 |
for(I=SPRITES16? 16:8;I>0;I--,P++) |
| 277 |
{ |
| 278 |
for(K=0x80;K;K>>=1) |
| 279 |
printf("%c",P[0]&K? (P[8]&K? '#':'o'):(P[8]&K? 'O':'.')); |
| 280 |
printf("\n"); |
| 281 |
if(I==9) P+=8; |
| 282 |
} |
| 283 |
printf("--------\n"); |
| 284 |
} |
| 285 |
else |
| 286 |
{ |
| 287 |
printf("\nNo| Position | Pat | Att |No| Position | Pat | Att |No| Position | Pat | Att\n"); |
| 288 |
for(J=I=0;J<64*4;J+=4) |
| 289 |
if(!J||(SRAM[J]&&SRAM[J+3]&&(SRAM[J]<240))) |
| 290 |
{ |
| 291 |
printf |
| 292 |
( |
| 293 |
"%2d| %3d,%3d | $%02X | $%02X %s", |
| 294 |
J/4,SRAM[J+3],SRAM[J],SRAM[J+1],SRAM[J+2], |
| 295 |
I%3==2? "\n":"|" |
| 296 |
); |
| 297 |
I++; |
| 298 |
} |
| 299 |
} |
| 300 |
break; |
| 301 |
#endif /* INES */ |
| 302 |
} |
| 303 |
} |
| 304 |
|
| 305 |
/* Continue with emulation */ |
| 306 |
return(1); |
| 307 |
} |
| 308 |
|
| 309 |
#endif /* DEBUG */ |
Parent Directory
| 
Revision Log