555 lines
19 KiB
C++
555 lines
19 KiB
C++
/// \file
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/// \brief 6502 assembler and disassembler
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#include "types.h"
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#include "utils/xstring.h"
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#include "utils/StringBuilder.h"
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#include "debug.h"
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#include "asm.h"
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#include "x6502.h"
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#include <cstring>
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#include <cstdlib>
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#include <cstdio>
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///assembles the string to an instruction located at addr, storing opcodes in output buffer
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int Assemble(unsigned char *output, int addr, char *str) {
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//unsigned char opcode[3] = { 0,0,0 };
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output[0] = output[1] = output[2] = 0;
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char astr[128],ins[4];
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int len = strlen(str);
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if ((!len) || (len > 127)) return 1;
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strcpy(astr,str);
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str_ucase(astr);
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sscanf(astr,"%3s",ins); //get instruction
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if (strlen(ins) != 3) return 1;
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strcpy(astr,strstr(astr,ins)+3); //heheh, this is probably a bad idea, but let's do it anyway!
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if ((astr[0] != ' ') && (astr[0] != 0)) return 1;
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//remove all whitespace
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str_strip(astr,STRIP_SP|STRIP_TAB|STRIP_CR|STRIP_LF);
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//repair syntax
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chr_replace(astr,'[','('); //brackets
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chr_replace(astr,']',')');
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chr_replace(astr,'{','(');
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chr_replace(astr,'}',')');
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chr_replace(astr,';',0); //comments
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str_replace(astr,"0X","$"); //miscellaneous
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//This does the following:
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// 1) Sets opcode[0] on success, else returns 1.
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// 2) Parses text in *astr to build the rest of the assembled
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// data in 'opcode', else returns 1 on error.
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if (!strlen(astr)) {
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//Implied instructions
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if (!strcmp(ins,"BRK")) output[0] = 0x00;
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else if (!strcmp(ins,"PHP")) output[0] = 0x08;
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else if (!strcmp(ins,"ASL")) output[0] = 0x0A;
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else if (!strcmp(ins,"CLC")) output[0] = 0x18;
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else if (!strcmp(ins,"PLP")) output[0] = 0x28;
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else if (!strcmp(ins,"ROL")) output[0] = 0x2A;
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else if (!strcmp(ins,"SEC")) output[0] = 0x38;
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else if (!strcmp(ins,"RTI")) output[0] = 0x40;
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else if (!strcmp(ins,"PHA")) output[0] = 0x48;
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else if (!strcmp(ins,"LSR")) output[0] = 0x4A;
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else if (!strcmp(ins,"CLI")) output[0] = 0x58;
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else if (!strcmp(ins,"RTS")) output[0] = 0x60;
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else if (!strcmp(ins,"PLA")) output[0] = 0x68;
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else if (!strcmp(ins,"ROR")) output[0] = 0x6A;
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else if (!strcmp(ins,"SEI")) output[0] = 0x78;
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else if (!strcmp(ins,"DEY")) output[0] = 0x88;
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else if (!strcmp(ins,"TXA")) output[0] = 0x8A;
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else if (!strcmp(ins,"TYA")) output[0] = 0x98;
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else if (!strcmp(ins,"TXS")) output[0] = 0x9A;
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else if (!strcmp(ins,"TAY")) output[0] = 0xA8;
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else if (!strcmp(ins,"TAX")) output[0] = 0xAA;
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else if (!strcmp(ins,"CLV")) output[0] = 0xB8;
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else if (!strcmp(ins,"TSX")) output[0] = 0xBA;
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else if (!strcmp(ins,"INY")) output[0] = 0xC8;
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else if (!strcmp(ins,"DEX")) output[0] = 0xCA;
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else if (!strcmp(ins,"CLD")) output[0] = 0xD8;
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else if (!strcmp(ins,"INX")) output[0] = 0xE8;
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else if (!strcmp(ins,"NOP")) output[0] = 0xEA;
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else if (!strcmp(ins,"SED")) output[0] = 0xF8;
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else return 1;
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}
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else {
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//Instructions with Operands
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if (!strcmp(ins,"ORA")) output[0] = 0x01;
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else if (!strcmp(ins,"ASL")) output[0] = 0x06;
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else if (!strcmp(ins,"BPL")) output[0] = 0x10;
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else if (!strcmp(ins,"JSR")) output[0] = 0x20;
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else if (!strcmp(ins,"AND")) output[0] = 0x21;
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else if (!strcmp(ins,"BIT")) output[0] = 0x24;
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else if (!strcmp(ins,"ROL")) output[0] = 0x26;
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else if (!strcmp(ins,"BMI")) output[0] = 0x30;
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else if (!strcmp(ins,"EOR")) output[0] = 0x41;
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else if (!strcmp(ins,"LSR")) output[0] = 0x46;
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else if (!strcmp(ins,"JMP")) output[0] = 0x4C;
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else if (!strcmp(ins,"BVC")) output[0] = 0x50;
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else if (!strcmp(ins,"ADC")) output[0] = 0x61;
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else if (!strcmp(ins,"ROR")) output[0] = 0x66;
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else if (!strcmp(ins,"BVS")) output[0] = 0x70;
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else if (!strcmp(ins,"STA")) output[0] = 0x81;
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else if (!strcmp(ins,"STY")) output[0] = 0x84;
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else if (!strcmp(ins,"STX")) output[0] = 0x86;
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else if (!strcmp(ins,"BCC")) output[0] = 0x90;
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else if (!strcmp(ins,"LDY")) output[0] = 0xA0;
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else if (!strcmp(ins,"LDA")) output[0] = 0xA1;
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else if (!strcmp(ins,"LDX")) output[0] = 0xA2;
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else if (!strcmp(ins,"BCS")) output[0] = 0xB0;
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else if (!strcmp(ins,"CPY")) output[0] = 0xC0;
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else if (!strcmp(ins,"CMP")) output[0] = 0xC1;
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else if (!strcmp(ins,"DEC")) output[0] = 0xC6;
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else if (!strcmp(ins,"BNE")) output[0] = 0xD0;
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else if (!strcmp(ins,"CPX")) output[0] = 0xE0;
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else if (!strcmp(ins,"SBC")) output[0] = 0xE1;
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else if (!strcmp(ins,"INC")) output[0] = 0xE6;
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else if (!strcmp(ins,"BEQ")) output[0] = 0xF0;
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else return 1;
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{
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//Parse Operands
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// It's not the sexiest thing ever, but it works well enough!
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//TODO:
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// Add branches.
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// Fix certain instructions. (Setting bits is not 100% perfect.)
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// Fix instruction/operand matching. (Instructions like "jmp ($94),Y" are no good!)
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// Optimizations?
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int tmpint;
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char tmpchr,tmpstr[20];
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if (sscanf(astr,"#$%2X%c",&tmpint,&tmpchr) == 1) { //#Immediate
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switch (output[0]) {
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case 0x20: case 0x4C: //Jumps
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case 0x10: case 0x30: case 0x50: case 0x70: //Branches
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case 0x90: case 0xB0: case 0xD0: case 0xF0:
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case 0x06: case 0x24: case 0x26: case 0x46: //Other instructions incapable of #Immediate
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case 0x66: case 0x81: case 0x84: case 0x86:
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case 0xC6: case 0xE6:
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return 1;
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default:
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//cheap hack for certain instructions
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switch (output[0]) {
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case 0xA0: case 0xA2: case 0xC0: case 0xE0:
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break;
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default:
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output[0] |= 0x08;
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break;
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}
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output[1] = tmpint;
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break;
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}
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}
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else if (sscanf(astr,"$%4X%c",&tmpint,&tmpchr) == 1) { //Absolute, Zero Page, Branch, or Jump
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switch (output[0]) {
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case 0x20: case 0x4C: //Jumps
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output[1] = (tmpint & 0xFF);
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output[2] = (tmpint >> 8);
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break;
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case 0x10: case 0x30: case 0x50: case 0x70: //Branches
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case 0x90: case 0xB0: case 0xD0: case 0xF0:
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tmpint -= (addr+2);
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if ((tmpint < -128) || (tmpint > 127)) return 1;
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output[1] = (tmpint & 0xFF);
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break;
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//return 1; //FIX ME
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default:
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if (tmpint > 0xFF) { //Absolute
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output[0] |= 0x0C;
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output[1] = (tmpint & 0xFF);
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output[2] = (tmpint >> 8);
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}
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else { //Zero Page
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output[0] |= 0x04;
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output[1] = (tmpint & 0xFF);
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}
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break;
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}
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}
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else if (sscanf(astr,"$%4X%s",&tmpint,tmpstr) == 2) { //Absolute,X, Zero Page,X, Absolute,Y or Zero Page,Y
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if (!strcmp(tmpstr,",X")) { //Absolute,X or Zero Page,X
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switch (output[0]) {
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case 0x20: case 0x4C: //Jumps
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case 0x10: case 0x30: case 0x50: case 0x70: //Branches
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case 0x90: case 0xB0: case 0xD0: case 0xF0:
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case 0x24: case 0x86: case 0xA2: case 0xC0: //Other instructions incapable of Absolute,X or Zero Page,X
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case 0xE0:
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return 1;
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default:
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if (tmpint > 0xFF) { //Absolute
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if (output[0] == 0x84) return 1; //No STY Absolute,X!
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output[0] |= 0x1C;
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output[1] = (tmpint & 0xFF);
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output[2] = (tmpint >> 8);
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}
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else { //Zero Page
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output[0] |= 0x14;
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output[1] = (tmpint & 0xFF);
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}
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break;
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}
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}
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else if (!strcmp(tmpstr,",Y")) { //Absolute,Y or Zero Page,Y
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switch (output[0]) {
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case 0x20: case 0x4C: //Jumps
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case 0x10: case 0x30: case 0x50: case 0x70: //Branches
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case 0x90: case 0xB0: case 0xD0: case 0xF0:
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case 0x06: case 0x24: case 0x26: case 0x46: //Other instructions incapable of Absolute,Y or Zero Page,Y
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case 0x66: case 0x84: case 0x86: case 0xA0:
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case 0xC0: case 0xC6: case 0xE0: case 0xE6:
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return 1;
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case 0xA2: //cheap hack for LDX
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output[0] |= 0x04;
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default:
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if (tmpint > 0xFF) { //Absolute
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if (output[0] == 0x86) return 1; //No STX Absolute,Y!
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output[0] |= 0x18;
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output[1] = (tmpint & 0xFF);
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output[2] = (tmpint >> 8);
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}
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else { //Zero Page
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if ((output[0] != 0x86) && (output[0] != 0xA2)) return 1; //only STX and LDX Absolute,Y!
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output[0] |= 0x10;
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output[1] = (tmpint & 0xFF);
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}
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break;
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}
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}
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else return 1;
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}
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else if (sscanf(astr,"($%4X%s",&tmpint,tmpstr) == 2) { //Jump (Indirect), (Indirect,X) or (Indirect),Y
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switch (output[0]) {
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case 0x20: //Jumps
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case 0x10: case 0x30: case 0x50: case 0x70: //Branches
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case 0x90: case 0xB0: case 0xD0: case 0xF0:
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case 0x06: case 0x24: case 0x26: case 0x46: //Other instructions incapable of Jump (Indirect), (Indirect,X) or (Indirect),Y
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case 0x66: case 0x84: case 0x86: case 0xA0:
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case 0xA2: case 0xC0: case 0xC6: case 0xE0:
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case 0xE6:
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return 1;
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default:
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if ((!strcmp(tmpstr,")")) && (output[0] == 0x4C)) { //Jump (Indirect)
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output[0] = 0x6C;
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output[1] = (tmpint & 0xFF);
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output[2] = (tmpint >> 8);
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}
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else if ((!strcmp(tmpstr,",X)")) && (tmpint <= 0xFF) && (output[0] != 0x4C)) { //(Indirect,X)
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output[1] = (tmpint & 0xFF);
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}
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else if ((!strcmp(tmpstr,"),Y")) && (tmpint <= 0xFF) && (output[0] != 0x4C)) { //(Indirect),Y
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output[0] |= 0x10;
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output[1] = (tmpint & 0xFF);
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}
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else return 1;
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break;
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}
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}
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else return 1;
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}
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}
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return 0;
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}
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///disassembles the opcodes in the buffer assuming the provided address. Uses GetMem() and 6502 current registers to query referenced values. returns a static string buffer.
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char *Disassemble(int addr, uint8 *opcode) {
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static char str[64]={0};
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const char *chr;
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char indReg;
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uint16 tmp,tmp2;
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StringBuilder sb(str);
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//these may be replaced later with passed-in values to make a lighter-weight disassembly mode that may not query the referenced values
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#define RX (X.X)
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#define RY (X.Y)
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switch (opcode[0]) {
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#define relative(a) { \
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if (((a)=opcode[1])&0x80) (a) = addr-(((a)-1)^0xFF); \
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else (a)+=addr; \
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}
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#define absolute(a) { \
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(a) = opcode[1] | opcode[2]<<8; \
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}
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#define zpIndex(a,i) { \
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(a) = (opcode[1]+(i))&0xFF; \
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}
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#define indirectX(a) { \
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(a) = (opcode[1]+RX)&0xFF; \
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(a) = GetMem((a)) | (GetMem(((a)+1)&0xff))<<8; \
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}
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#define indirectY(a) { \
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(a) = GetMem(opcode[1]) | (GetMem((opcode[1]+1)&0xff))<<8; \
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(a) += RY; \
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}
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#ifdef BRK_3BYTE_HACK
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case 0x00:
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sb << "BRK " << sb_hex(opcode[1], 2) << ' ' << sb_hex(opcode[2], 2);
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break;
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#else
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case 0x00: strcpy(str,"BRK"); break;
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#endif
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//odd, 1-byte opcodes
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case 0x08: strcpy(str,"PHP"); break;
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case 0x0A: strcpy(str,"ASL"); break;
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case 0x18: strcpy(str,"CLC"); break;
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case 0x28: strcpy(str,"PLP"); break;
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case 0x2A: strcpy(str,"ROL"); break;
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case 0x38: strcpy(str,"SEC"); break;
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case 0x40: strcpy(str,"RTI"); break;
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case 0x48: strcpy(str,"PHA"); break;
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case 0x4A: strcpy(str,"LSR"); break;
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case 0x58: strcpy(str,"CLI"); break;
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case 0x60: strcpy(str,"RTS"); break;
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case 0x68: strcpy(str,"PLA"); break;
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case 0x6A: strcpy(str,"ROR"); break;
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case 0x78: strcpy(str,"SEI"); break;
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case 0x88: strcpy(str,"DEY"); break;
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case 0x8A: strcpy(str,"TXA"); break;
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case 0x98: strcpy(str,"TYA"); break;
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case 0x9A: strcpy(str,"TXS"); break;
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case 0xA8: strcpy(str,"TAY"); break;
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case 0xAA: strcpy(str,"TAX"); break;
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case 0xB8: strcpy(str,"CLV"); break;
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case 0xBA: strcpy(str,"TSX"); break;
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case 0xC8: strcpy(str,"INY"); break;
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case 0xCA: strcpy(str,"DEX"); break;
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case 0xD8: strcpy(str,"CLD"); break;
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case 0xE8: strcpy(str,"INX"); break;
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case 0xEA: strcpy(str,"NOP"); break;
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case 0xF8: strcpy(str,"SED"); break;
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//(Indirect,X)
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case 0x01: chr = "ORA"; goto _indirectx;
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case 0x21: chr = "AND"; goto _indirectx;
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case 0x41: chr = "EOR"; goto _indirectx;
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case 0x61: chr = "ADC"; goto _indirectx;
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case 0x81: chr = "STA"; goto _indirectx;
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case 0xA1: chr = "LDA"; goto _indirectx;
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case 0xC1: chr = "CMP"; goto _indirectx;
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case 0xE1: chr = "SBC"; goto _indirectx;
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_indirectx:
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indirectX(tmp);
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indReg = 'X';
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_indirect:
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sb << chr << " (" << sb_addr(opcode[1], 2) << ',' << indReg << ") @ " << sb_addr(tmp) << " = " << sb_lit(GetMem(tmp));
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break;
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//Zero Page
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case 0x05: chr = "ORA"; goto _zeropage;
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case 0x06: chr = "ASL"; goto _zeropage;
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case 0x24: chr = "BIT"; goto _zeropage;
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case 0x25: chr = "AND"; goto _zeropage;
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case 0x26: chr = "ROL"; goto _zeropage;
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case 0x45: chr = "EOR"; goto _zeropage;
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case 0x46: chr = "LSR"; goto _zeropage;
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case 0x65: chr = "ADC"; goto _zeropage;
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case 0x66: chr = "ROR"; goto _zeropage;
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case 0x84: chr = "STY"; goto _zeropage;
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case 0x85: chr = "STA"; goto _zeropage;
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case 0x86: chr = "STX"; goto _zeropage;
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case 0xA4: chr = "LDY"; goto _zeropage;
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case 0xA5: chr = "LDA"; goto _zeropage;
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case 0xA6: chr = "LDX"; goto _zeropage;
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case 0xC4: chr = "CPY"; goto _zeropage;
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case 0xC5: chr = "CMP"; goto _zeropage;
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case 0xC6: chr = "DEC"; goto _zeropage;
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case 0xE4: chr = "CPX"; goto _zeropage;
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case 0xE5: chr = "SBC"; goto _zeropage;
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case 0xE6: chr = "INC"; goto _zeropage;
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_zeropage:
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// ################################## Start of SP CODE ###########################
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// Change width to %04X // don't!
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sb << chr << ' ' << sb_addr(opcode[1], 2) << " = " << sb_lit(GetMem(opcode[1]));
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// ################################## End of SP CODE ###########################
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break;
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//#Immediate
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case 0x09: chr = "ORA"; goto _immediate;
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case 0x29: chr = "AND"; goto _immediate;
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case 0x49: chr = "EOR"; goto _immediate;
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case 0x69: chr = "ADC"; goto _immediate;
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//case 0x89: chr = "STA"; goto _immediate; //baka, no STA #imm!!
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case 0xA0: chr = "LDY"; goto _immediate;
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case 0xA2: chr = "LDX"; goto _immediate;
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case 0xA9: chr = "LDA"; goto _immediate;
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case 0xC0: chr = "CPY"; goto _immediate;
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case 0xC9: chr = "CMP"; goto _immediate;
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case 0xE0: chr = "CPX"; goto _immediate;
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case 0xE9: chr = "SBC"; goto _immediate;
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_immediate:
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sb << chr << ' ' << sb_lit(opcode[1]);
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break;
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//Absolute
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case 0x0D: chr = "ORA"; goto _absolute;
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case 0x0E: chr = "ASL"; goto _absolute;
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case 0x2C: chr = "BIT"; goto _absolute;
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case 0x2D: chr = "AND"; goto _absolute;
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case 0x2E: chr = "ROL"; goto _absolute;
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case 0x4D: chr = "EOR"; goto _absolute;
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case 0x4E: chr = "LSR"; goto _absolute;
|
|
case 0x6D: chr = "ADC"; goto _absolute;
|
|
case 0x6E: chr = "ROR"; goto _absolute;
|
|
case 0x8C: chr = "STY"; goto _absolute;
|
|
case 0x8D: chr = "STA"; goto _absolute;
|
|
case 0x8E: chr = "STX"; goto _absolute;
|
|
case 0xAC: chr = "LDY"; goto _absolute;
|
|
case 0xAD: chr = "LDA"; goto _absolute;
|
|
case 0xAE: chr = "LDX"; goto _absolute;
|
|
case 0xCC: chr = "CPY"; goto _absolute;
|
|
case 0xCD: chr = "CMP"; goto _absolute;
|
|
case 0xCE: chr = "DEC"; goto _absolute;
|
|
case 0xEC: chr = "CPX"; goto _absolute;
|
|
case 0xED: chr = "SBC"; goto _absolute;
|
|
case 0xEE: chr = "INC"; goto _absolute;
|
|
_absolute:
|
|
absolute(tmp);
|
|
|
|
sb << chr << ' ' << sb_addr(tmp) << " = " << sb_lit(GetMem(tmp));
|
|
|
|
break;
|
|
|
|
//branches
|
|
case 0x10: chr = "BPL"; goto _branch;
|
|
case 0x30: chr = "BMI"; goto _branch;
|
|
case 0x50: chr = "BVC"; goto _branch;
|
|
case 0x70: chr = "BVS"; goto _branch;
|
|
case 0x90: chr = "BCC"; goto _branch;
|
|
case 0xB0: chr = "BCS"; goto _branch;
|
|
case 0xD0: chr = "BNE"; goto _branch;
|
|
case 0xF0: chr = "BEQ"; goto _branch;
|
|
_branch:
|
|
relative(tmp);
|
|
|
|
sb << chr << ' ' << sb_addr(tmp);
|
|
|
|
break;
|
|
|
|
//(Indirect),Y
|
|
case 0x11: chr = "ORA"; goto _indirecty;
|
|
case 0x31: chr = "AND"; goto _indirecty;
|
|
case 0x51: chr = "EOR"; goto _indirecty;
|
|
case 0x71: chr = "ADC"; goto _indirecty;
|
|
case 0x91: chr = "STA"; goto _indirecty;
|
|
case 0xB1: chr = "LDA"; goto _indirecty;
|
|
case 0xD1: chr = "CMP"; goto _indirecty;
|
|
case 0xF1: chr = "SBC"; goto _indirecty;
|
|
_indirecty:
|
|
indirectY(tmp);
|
|
indReg = 'Y';
|
|
|
|
goto _indirect;
|
|
|
|
//Zero Page,X
|
|
case 0x15: chr = "ORA"; goto _zeropagex;
|
|
case 0x16: chr = "ASL"; goto _zeropagex;
|
|
case 0x35: chr = "AND"; goto _zeropagex;
|
|
case 0x36: chr = "ROL"; goto _zeropagex;
|
|
case 0x55: chr = "EOR"; goto _zeropagex;
|
|
case 0x56: chr = "LSR"; goto _zeropagex;
|
|
case 0x75: chr = "ADC"; goto _zeropagex;
|
|
case 0x76: chr = "ROR"; goto _zeropagex;
|
|
case 0x94: chr = "STY"; goto _zeropagex;
|
|
case 0x95: chr = "STA"; goto _zeropagex;
|
|
case 0xB4: chr = "LDY"; goto _zeropagex;
|
|
case 0xB5: chr = "LDA"; goto _zeropagex;
|
|
case 0xD5: chr = "CMP"; goto _zeropagex;
|
|
case 0xD6: chr = "DEC"; goto _zeropagex;
|
|
case 0xF5: chr = "SBC"; goto _zeropagex;
|
|
case 0xF6: chr = "INC"; goto _zeropagex;
|
|
_zeropagex:
|
|
zpIndex(tmp, RX);
|
|
indReg = 'X';
|
|
|
|
_indexed:
|
|
// ################################## Start of SP CODE ###########################
|
|
// Change width to %04X // don't!
|
|
sb << chr << ' ' << sb_addr(opcode[1], 2) << ',' << indReg << " @ " << sb_addr(tmp) << " = " << sb_lit(GetMem(tmp));
|
|
// ################################## End of SP CODE ###########################
|
|
break;
|
|
|
|
//Absolute,Y
|
|
case 0x19: chr = "ORA"; goto _absolutey;
|
|
case 0x39: chr = "AND"; goto _absolutey;
|
|
case 0x59: chr = "EOR"; goto _absolutey;
|
|
case 0x79: chr = "ADC"; goto _absolutey;
|
|
case 0x99: chr = "STA"; goto _absolutey;
|
|
case 0xB9: chr = "LDA"; goto _absolutey;
|
|
case 0xBE: chr = "LDX"; goto _absolutey;
|
|
case 0xD9: chr = "CMP"; goto _absolutey;
|
|
case 0xF9: chr = "SBC"; goto _absolutey;
|
|
_absolutey:
|
|
absolute(tmp);
|
|
tmp2 = (tmp + RY);
|
|
indReg = 'Y';
|
|
|
|
_absindexed:
|
|
sb << chr << ' ' << sb_addr(tmp) << ',' << indReg << " @ " << sb_addr(tmp2) << " = " << sb_lit(GetMem(tmp2));
|
|
|
|
break;
|
|
|
|
//Absolute,X
|
|
case 0x1D: chr = "ORA"; goto _absolutex;
|
|
case 0x1E: chr = "ASL"; goto _absolutex;
|
|
case 0x3D: chr = "AND"; goto _absolutex;
|
|
case 0x3E: chr = "ROL"; goto _absolutex;
|
|
case 0x5D: chr = "EOR"; goto _absolutex;
|
|
case 0x5E: chr = "LSR"; goto _absolutex;
|
|
case 0x7D: chr = "ADC"; goto _absolutex;
|
|
case 0x7E: chr = "ROR"; goto _absolutex;
|
|
case 0x9D: chr = "STA"; goto _absolutex;
|
|
case 0xBC: chr = "LDY"; goto _absolutex;
|
|
case 0xBD: chr = "LDA"; goto _absolutex;
|
|
case 0xDD: chr = "CMP"; goto _absolutex;
|
|
case 0xDE: chr = "DEC"; goto _absolutex;
|
|
case 0xFD: chr = "SBC"; goto _absolutex;
|
|
case 0xFE: chr = "INC"; goto _absolutex;
|
|
_absolutex:
|
|
absolute(tmp);
|
|
tmp2 = (tmp + RX);
|
|
indReg = 'X';
|
|
|
|
goto _absindexed;
|
|
|
|
//jumps
|
|
case 0x20: chr = "JSR"; goto _jump;
|
|
case 0x4C: chr = "JMP"; goto _jump;
|
|
_jump:
|
|
absolute(tmp);
|
|
|
|
sb << chr << ' ' << sb_addr(tmp);
|
|
|
|
break;
|
|
|
|
case 0x6C:
|
|
absolute(tmp);
|
|
|
|
sb << "JMP (" << sb_addr(tmp);
|
|
sb << ") = " << sb_addr(GetMem(tmp) | GetMem(tmp + 1) << 8);
|
|
|
|
break;
|
|
|
|
//Zero Page,Y
|
|
case 0x96: chr = "STX"; goto _zeropagey;
|
|
case 0xB6: chr = "LDX"; goto _zeropagey;
|
|
_zeropagey:
|
|
zpIndex(tmp, RY);
|
|
indReg = 'Y';
|
|
|
|
goto _indexed;
|
|
|
|
//UNDEFINED
|
|
default: strcpy(str, "ERROR"); break;
|
|
}
|
|
return str;
|
|
}
|