455 lines
12 KiB
JavaScript
455 lines
12 KiB
JavaScript
/**
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* @fileoverview Implements PC8080 opcode handlers.
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* @author <a href="mailto:Jeff@pcjs.org">Jeff Parsons</a>
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* @version 1.0
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* Created 2016-Apr-20
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*
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* Copyright © 2012-2016 Jeff Parsons <Jeff@pcjs.org>
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*
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* This file is part of PCjs, which is part of the JavaScript Machines Project (aka JSMachines)
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* at <http://jsmachines.net/> and <http://pcjs.org/>.
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*
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* PCjs is free software: you can redistribute it and/or modify it under the terms of the
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* GNU General Public License as published by the Free Software Foundation, either version 3
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* of the License, or (at your option) any later version.
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*
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* PCjs is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without
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* even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License along with PCjs. If not,
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* see <http://www.gnu.org/licenses/gpl.html>.
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*
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* You are required to include the above copyright notice in every source code file of every
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* copy or modified version of this work, and to display that copyright notice on every screen
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* that loads or runs any version of this software (see Computer.COPYRIGHT).
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*
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* Some PCjs files also attempt to load external resource files, such as character-image files,
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* ROM files, and disk image files. Those external resource files are not considered part of the
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* PCjs program for purposes of the GNU General Public License, and the author does not claim
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* any copyright as to their contents.
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*/
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"use strict";
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if (NODE) {
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var str = require("../../shared/lib/strlib");
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var Messages = require("./messages");
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var CPUDef = require("./CPUDef");
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}
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/**
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* op=0x00 (NOP)
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*
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* @this {CPUSim}
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*/
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CPUDef.opNOP = function()
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{
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this.nStepCycles -= 4;
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};
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/**
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* op=0x01 (LXI B,d16)
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*
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* @this {CPUSim}
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*/
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CPUDef.opLXIB = function()
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{
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this.setBC(this.getPCWord());
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this.nStepCycles -= 10;
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};
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/**
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* op=0x02 (STAX B)
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*
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* @this {CPUSim}
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*/
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CPUDef.opSTAXB = function()
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{
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this.setByte(this.getBC(), this.regA);
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this.nStepCycles -= 7;
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};
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/**
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* op=0x03 (INX B)
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*
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* @this {CPUSim}
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*/
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CPUDef.opINXB = function()
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{
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this.setBC(this.getBC() + 1);
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this.nStepCycles -= 5;
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};
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/**
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* op=0x04 (INR B)
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*
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* @this {CPUSim}
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*/
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CPUDef.opINRB = function()
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{
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this.regB = this.incByte(this.regB);
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this.nStepCycles -= 5;
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};
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/**
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* op=0x05 (DCR B)
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*
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* @this {CPUSim}
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*/
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CPUDef.opDCRB = function()
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{
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this.regB = this.decByte(this.regB);
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this.nStepCycles -= 5;
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};
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/**
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* op=0x06 (MVI B,d8)
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*
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* @this {CPUSim}
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*/
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CPUDef.opMVIB = function()
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{
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this.regB = this.getPCByte();
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this.nStepCycles -= 7;
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};
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/**
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* op=0x07 (RLC)
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*
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* @this {CPUSim}
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*/
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CPUDef.opRLC = function()
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{
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var carry = this.regA << 1;
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this.regA = (carry & 0xff) | (carry >> 8);
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this.resultZeroCarry = (this.resultZeroCarry & 0xff) | (carry & 0x100);
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this.nStepCycles -= 4;
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};
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/**
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* op=0x09 (DAD B)
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*
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* @this {CPUSim}
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*/
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CPUDef.opDADB = function()
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{
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var w;
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this.setHL(w = this.getHL() + this.getBC());
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this.resultZeroCarry = (this.resultZeroCarry & 0xff) | ((w >> 8) & 0x100);
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this.nStepCycles -= 10;
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};
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/**
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* op=0x0A (LDAX B)
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*
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* @this {CPUSim}
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*/
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CPUDef.opLDAXB = function()
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{
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this.regA = this.getByte(this.getBC());
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this.nStepCycles -= 7;
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};
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/**
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* op=0x0B (DCX B)
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*
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* @this {CPUSim}
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*/
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CPUDef.opDCXB = function()
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{
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this.setBC(this.getBC() - 1);
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this.nStepCycles -= 5;
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};
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/**
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* op=0x0C (INR C)
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*
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* @this {CPUSim}
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*/
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CPUDef.opINRC = function()
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{
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this.regC = this.incByte(this.regC);
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this.nStepCycles -= 5;
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};
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/**
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* op=0x0D (DCR C)
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*
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* @this {CPUSim}
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*/
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CPUDef.opDCRC = function()
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{
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this.regC = this.decByte(this.regC);
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this.nStepCycles -= 5;
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};
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/**
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* op=0x0E (MVI C,d8)
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*
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* @this {CPUSim}
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*/
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CPUDef.opMVIC = function()
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{
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this.regC = this.getPCByte();
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this.nStepCycles -= 7;
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};
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/**
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* op=0x0F (RRC)
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*
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* @this {CPUSim}
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*/
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CPUDef.opRRC = function()
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{
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var carry = (this.regA << 8) & 0x100;
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this.regA = (carry | this.regA) >> 1;
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this.resultZeroCarry = (this.resultZeroCarry & 0xff) | carry;
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this.nStepCycles -= 4;
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};
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/**
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* op=0x11 (LXI D,d16)
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*
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* @this {CPUSim}
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*/
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CPUDef.opLXID = function()
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{
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this.setDE(this.getPCWord());
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this.nStepCycles -= 10;
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};
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/**
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* op=0x12 (STAX D)
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*
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* @this {CPUSim}
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*/
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CPUDef.opSTAXD = function()
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{
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this.setByte(this.getDE(), this.regA);
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this.nStepCycles -= 7;
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};
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/**
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* op=0x13 (INX D)
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*
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* @this {CPUSim}
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*/
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CPUDef.opINXD = function()
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{
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this.setDE(this.getDE() + 1);
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this.nStepCycles -= 5;
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};
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/**
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* op=0x14 (INR D)
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*
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* @this {CPUSim}
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*/
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CPUDef.opINRD = function()
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{
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this.regD = this.incByte(this.regD);
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this.nStepCycles -= 5;
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};
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/**
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* op=0x15 (DCR D)
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*
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* @this {CPUSim}
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*/
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CPUDef.opDCRD = function()
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{
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this.regD = this.decByte(this.regD);
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this.nStepCycles -= 5;
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};
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/**
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* op=0x16 (MVI D,d8)
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*
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* @this {CPUSim}
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*/
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CPUDef.opMVID = function()
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{
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this.regD = this.getPCByte();
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this.nStepCycles -= 7;
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};
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/**
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* op=0x17 (RAL)
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*
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* @this {CPUSim}
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*/
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CPUDef.opRAL = function()
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{
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var carry = this.regA << 1;
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this.regA = (carry & 0xff) | (this.resultZeroCarry >> 8);
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this.resultZeroCarry = (this.resultZeroCarry & 0xff) | (carry & 0x100);
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this.nStepCycles -= 4;
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};
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/**
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* op=0x19 (DAD D)
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*
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* @this {CPUSim}
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*/
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CPUDef.opDADD = function()
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{
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var w;
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this.setHL(w = this.getHL() + this.getDE());
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this.resultZeroCarry = (this.resultZeroCarry & 0xff) | ((w >> 8) & 0x100);
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this.nStepCycles -= 10;
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};
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/**
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* op=0x1A (LDAX D)
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*
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* @this {CPUSim}
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*/
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CPUDef.opLDAXD = function()
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{
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this.regA = this.getByte(this.getDE());
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this.nStepCycles -= 7;
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};
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/**
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* op=0x1B (DCX D)
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*
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* @this {CPUSim}
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*/
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CPUDef.opDCXD = function()
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{
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this.setDE(this.getDE() - 1);
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this.nStepCycles -= 5;
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};
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/**
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* op=0x1C (INR E)
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*
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* @this {CPUSim}
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*/
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CPUDef.opINRE = function()
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{
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this.regE = this.incByte(this.regE);
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this.nStepCycles -= 5;
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};
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/**
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* op=0x1D (DCR E)
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*
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* @this {CPUSim}
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*/
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CPUDef.opDCRE = function()
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{
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this.regE = this.decByte(this.regE);
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this.nStepCycles -= 5;
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};
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/**
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* op=0x1E (MVI E,d8)
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*
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* @this {CPUSim}
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*/
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CPUDef.opMVIE = function()
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{
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this.regE = this.getPCByte();
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this.nStepCycles -= 7;
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};
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/**
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* op=0x1F (RAR)
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*
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* @this {CPUSim}
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*/
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CPUDef.opRAR = function()
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{
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var carry = (this.regA << 8) & 0x100;
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this.regA = ((this.resultZeroCarry & 0x100) | this.regA) >> 1;
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this.resultZeroCarry = (this.resultZeroCarry & 0xff) | carry;
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this.nStepCycles -= 4;
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};
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/**
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* opTBD()
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*
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* @this {CPUSim}
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*/
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CPUDef.opTBD = function()
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{
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this.setPC(this.getPC() - 1);
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this.printMessage("unimplemented opcode", true);
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this.stopCPU();
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};
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/*
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* This 256-entry array of opcode functions is at the heart of the CPU engine: stepCPU(n).
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*
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* It might be worth trying a switch() statement instead, to see how the performance compares,
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* but I suspect that would vary quite a bit across JavaScript engines; for now, I'm putting my
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* money on array lookup.
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*/
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CPUDef.aOps = [
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/* 0x00-0x03 */ CPUDef.opNOP, CPUDef.opLXIB, CPUDef.opSTAXB, CPUDef.opINXB,
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/* 0x04-0x07 */ CPUDef.opINRB, CPUDef.opDCRB, CPUDef.opMVIB, CPUDef.opRLC,
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/* 0x08-0x0B */ CPUDef.opNOP, CPUDef.opDADB, CPUDef.opLDAXB, CPUDef.opDCXB,
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/* 0x0C-0x0F */ CPUDef.opINRC, CPUDef.opDCRC, CPUDef.opMVIC, CPUDef.opRRC,
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/* 0x10-0x13 */ CPUDef.opNOP, CPUDef.opLXID, CPUDef.opSTAXD, CPUDef.opINXD,
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/* 0x14-0x17 */ CPUDef.opINRD, CPUDef.opDCRD, CPUDef.opMVID, CPUDef.opRAL,
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/* 0x18-0x1B */ CPUDef.opNOP, CPUDef.opDADD, CPUDef.opLDAXD, CPUDef.opDCXD,
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/* 0x1C-0x1F */ CPUDef.opINRE, CPUDef.opDCRE, CPUDef.opMVIE, CPUDef.opRAR,
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/* 0x20-0x23 */ CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD,
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/* 0x24-0x27 */ CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD,
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/* 0x28-0x2B */ CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD,
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/* 0x2C-0x2F */ CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD,
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/* 0x30-0x33 */ CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD,
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/* 0x34-0x37 */ CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD,
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/* 0x38-0x3B */ CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD,
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/* 0x3C-0x3F */ CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD,
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/* 0x40-0x43 */ CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD,
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/* 0x44-0x47 */ CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD,
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/* 0x48-0x4B */ CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD,
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/* 0x4C-0x4F */ CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD,
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/* 0x50-0x53 */ CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD,
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/* 0x54-0x57 */ CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD,
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/* 0x58-0x5B */ CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD,
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/* 0x5C-0x5F */ CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD,
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/* 0x60-0x63 */ CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD,
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/* 0x64-0x67 */ CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD,
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/* 0x68-0x6B */ CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD,
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/* 0x6C-0x6F */ CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD,
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/* 0x70-0x73 */ CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD,
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/* 0x74-0x77 */ CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD,
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/* 0x78-0x7B */ CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD,
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/* 0x7C-0x7F */ CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD,
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/* 0x80-0x83 */ CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD,
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/* 0x84-0x87 */ CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD,
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/* 0x88-0x8B */ CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD,
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/* 0x8C-0x8F */ CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD,
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/* 0x90-0x93 */ CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD,
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/* 0x94-0x97 */ CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD,
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/* 0x98-0x9B */ CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD,
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/* 0x9C-0x9F */ CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD,
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/* 0xA0-0xA3 */ CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD,
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/* 0xA4-0xA7 */ CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD,
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/* 0xA8-0xAB */ CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD,
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/* 0xAC-0xAF */ CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD,
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/* 0xB0-0xB3 */ CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD,
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/* 0xB4-0xB7 */ CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD,
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/* 0xB8-0xBB */ CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD,
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/* 0xBC-0xBF */ CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD,
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/* 0xC0-0xC3 */ CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD,
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/* 0xC4-0xC7 */ CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD,
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/* 0xC8-0xCB */ CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD,
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/* 0xCC-0xCF */ CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD,
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/* 0xD0-0xD3 */ CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD,
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/* 0xD4-0xD7 */ CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD,
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/* 0xD8-0xDB */ CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD,
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/* 0xDC-0xDF */ CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD,
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/* 0xE0-0xE3 */ CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD,
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/* 0xE4-0xE7 */ CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD,
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/* 0xE8-0xEB */ CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD,
|
|
/* 0xEC-0xEF */ CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD,
|
|
/* 0xF0-0xF3 */ CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD,
|
|
/* 0xF4-0xF7 */ CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD,
|
|
/* 0xF8-0xFB */ CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD,
|
|
/* 0xFC-0xFF */ CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD, CPUDef.opTBD
|
|
];
|