//
// Copyright (c) Adrian Conlon. All rights reserved.
//
namespace EightBit
{
using System;
using System.Collections.Generic;
public sealed class Disassembler
{
private ushort address = 0xffff;
private bool prefix10 = false;
private bool prefix11 = false;
public Disassembler(Bus bus, MC6809 targetProcessor)
{
this.BUS = bus;
this.CPU = targetProcessor;
}
public bool Pause { get; set; } = false;
public bool Ignore => this.CPU.HALT.Lowered()
|| this.CPU.RESET.Lowered()
|| this.CPU.NMI.Lowered()
|| (this.CPU.FIRQ.Lowered() && this.CPU.FastInterruptMasked == 0)
|| (this.CPU.INT.Lowered() && this.CPU.InterruptMasked == 0);
private Bus BUS { get; }
private MC6809 CPU { get; }
public string Trace(ushort current)
{
var disassembled = this.Disassemble(current);
var cc = this.CPU.CC;
var a = this.CPU.A;
var b = this.CPU.B;
var dp = this.CPU.DP;
var x = this.CPU.X.Word;
var y = this.CPU.Y.Word;
var u = this.CPU.U.Word;
var s = this.CPU.S.Word;
return $"{current:x4}|{disassembled}\t\tcc={cc:x2} a={a:x2} b={b:x2} dp={dp:x2} x={x:x4} y={y:x4} u={u:x4} s={s:x4}";
}
public string Trace(Register16 current) => this.Trace(current.Word);
public string Trace() => this.Trace(this.CPU.PC);
public string Disassemble(ushort current)
{
this.address = current;
if (this.prefix10)
{
return this.Disassemble10();
}
if (this.prefix11)
{
return this.Disassemble11();
}
return this.DisassembleUnprefixed();
}
private static string RR(int which)
{
switch (which)
{
case 0b00:
return "X";
case 0b01:
return "Y";
case 0b10:
return "U";
case 0b11:
return "S";
default:
throw new ArgumentOutOfRangeException(nameof(which), which, "Register specification is unknown");
}
}
private static string WrapIndirect(string what, bool indirect)
{
var open = indirect ? "[" : string.Empty;
var close = indirect ? "]" : string.Empty;
return $"{open}{what}{close}";
}
private static string ReferenceTransfer8(int specifier)
{
switch (specifier)
{
case 0b1000:
return "A";
case 0b1001:
return "B";
case 0b1010:
return "CC";
case 0b1011:
return "DP";
default:
throw new ArgumentOutOfRangeException(nameof(specifier), specifier, "8bit register specification is unknown");
}
}
private static string ReferenceTransfer16(int specifier)
{
switch (specifier)
{
case 0b0000:
return "D";
case 0b0001:
return "X";
case 0b0010:
return "Y";
case 0b0011:
return "U";
case 0b0100:
return "S";
case 0b0101:
return "PC";
default:
throw new ArgumentOutOfRangeException(nameof(specifier), specifier, "16bit register specification is unknown");
}
}
private string Disassemble(int current) => this.Disassemble((ushort)current);
private string DisassembleUnprefixed()
{
var opcode = this.GetByte(this.address);
var output = $"{opcode:x2}";
switch (opcode)
{
case 0x10: this.prefix10 = true; output += this.Disassemble(this.address + 1); break;
case 0x11: this.prefix11 = true; output += this.Disassemble(this.address + 1); break;
// ABX
case 0x3a: output += "\tABX"; break; // ABX (inherent)
// ADC
case 0x89: output += this.AM_immediate_byte("ADCA"); break; // ADC (ADCA immediate)
case 0x99: output += this.Address_direct("ADCA"); break; // ADC (ADCA direct)
case 0xa9: output += this.Address_indexed("ADCA"); break; // ADC (ADCA indexed)
case 0xb9: output += this.Address_extended("ADCA"); break; // ADC (ADCA extended)
case 0xc9: output += this.AM_immediate_byte("ADCB"); break; // ADC (ADCB immediate)
case 0xd9: output += this.Address_direct("ADCB"); break; // ADC (ADCB direct)
case 0xe9: output += this.Address_indexed("ADCB"); break; // ADC (ADCB indexed)
case 0xf9: output += this.Address_extended("ADCB"); break; // ADC (ADCB extended)
// ADD
case 0x8b: output += this.AM_immediate_byte("ADDA"); break; // ADD (ADDA immediate)
case 0x9b: output += this.Address_direct("ADDA"); break; // ADD (ADDA direct)
case 0xab: output += this.Address_indexed("ADDA"); break; // ADD (ADDA indexed)
case 0xbb: output += this.Address_extended("ADDA"); break; // ADD (ADDA extended)
case 0xcb: output += this.AM_immediate_byte("ADDB"); break; // ADD (ADDB immediate)
case 0xdb: output += this.Address_direct("ADDB"); break; // ADD (ADDB direct)
case 0xeb: output += this.Address_indexed("ADDB"); break; // ADD (ADDB indexed)
case 0xfb: output += this.Address_extended("ADDB"); break; // ADD (ADDB extended)
case 0xc3: output += this.AM_immediate_word("ADDD"); break; // ADD (ADDD immediate)
case 0xd3: output += this.Address_direct("ADDD"); break; // ADD (ADDD direct)
case 0xe3: output += this.Address_indexed("ADDD"); break; // ADD (ADDD indexed)
case 0xf3: output += this.Address_extended("ADDD"); break; // ADD (ADDD extended)
// AND
case 0x84: output += this.AM_immediate_byte("ANDA"); break; // AND (ANDA immediate)
case 0x94: output += this.Address_direct("ANDA"); break; // AND (ANDA direct)
case 0xa4: output += this.Address_indexed("ANDA"); break; // AND (ANDA indexed)
case 0xb4: output += this.Address_extended("ANDA"); break; // AND (ANDA extended)
case 0xc4: output += this.AM_immediate_byte("ANDB"); break; // AND (ANDB immediate)
case 0xd4: output += this.Address_direct("ANDB"); break; // AND (ANDB direct)
case 0xe4: output += this.Address_indexed("ANDB"); break; // AND (ANDB indexed)
case 0xf4: output += this.Address_extended("ANDB"); break; // AND (ANDB extended)
case 0x1c: output += this.AM_immediate_byte("ANDCC"); break; // AND (ANDCC immediate)
// ASL/LSL
case 0x08: output += this.Address_direct("ASL"); break; // ASL (direct)
case 0x48: output += "\tASLA\t"; break; // ASL (ASLA inherent)
case 0x58: output += "\tASLB\t"; break; // ASL (ASLB inherent)
case 0x68: output += this.Address_indexed("ASL"); break; // ASL (indexed)
case 0x78: output += this.Address_extended("ASL"); break; // ASL (extended)
// ASR
case 0x07: output += this.Address_direct("ASR"); break; // ASR (direct)
case 0x47: output += "\tASRA\t"; break; // ASR (ASRA inherent)
case 0x57: output += "\tASRB\t"; break; // ASR (ASRB inherent)
case 0x67: output += this.Address_indexed("ASR"); break; // ASR (indexed)
case 0x77: output += this.Address_extended("ASR"); break; // ASR (extended)
// BIT
case 0x85: output += this.AM_immediate_byte("BITA"); break; // BIT (BITA immediate)
case 0x95: output += this.Address_direct("BITA"); break; // BIT (BITA direct)
case 0xa5: output += this.Address_indexed("BITA"); break; // BIT (BITA indexed)
case 0xb5: output += this.Address_extended("BITA"); break; // BIT (BITA extended)
case 0xc5: output += this.AM_immediate_byte("BITB"); break; // BIT (BITB immediate)
case 0xd5: output += this.Address_direct("BITB"); break; // BIT (BITB direct)
case 0xe5: output += this.Address_indexed("BITB"); break; // BIT (BITB indexed)
case 0xf5: output += this.Address_extended("BITB"); break; // BIT (BITB extended)
// CLR
case 0x0f: output += this.Address_direct("CLR"); break; // CLR (direct)
case 0x4f: output += "\tCLRA\t"; break; // CLR (CLRA implied)
case 0x5f: output += "\tCLRB\t"; break; // CLR (CLRB implied)
case 0x6f: output += this.Address_indexed("CLR"); break; // CLR (indexed)
case 0x7f: output += this.Address_extended("CLR"); break; // CLR (extended)
// CMP
// CMPA
case 0x81: output += this.AM_immediate_byte("CMPA"); break; // CMP (CMPA, immediate)
case 0x91: output += this.Address_direct("CMPA"); break; // CMP (CMPA, direct)
case 0xa1: output += this.Address_indexed("CMPA"); break; // CMP (CMPA, indexed)
case 0xb1: output += this.Address_extended("CMPA"); break; // CMP (CMPA, extended)
// CMPB
case 0xc1: output += this.AM_immediate_byte("CMPB"); break; // CMP (CMPB, immediate)
case 0xd1: output += this.Address_direct("CMPB"); break; // CMP (CMPB, direct)
case 0xe1: output += this.Address_indexed("CMPB"); break; // CMP (CMPB, indexed)
case 0xf1: output += this.Address_extended("CMPB"); break; // CMP (CMPB, extended)
// CMPX
case 0x8c: output += this.AM_immediate_word("CMPX"); break; // CMP (CMPX, immediate)
case 0x9c: output += this.Address_direct("CMPX"); break; // CMP (CMPX, direct)
case 0xac: output += this.Address_indexed("CMPX"); break; // CMP (CMPX, indexed)
case 0xbc: output += this.Address_extended("CMPX"); break; // CMP (CMPX, extended)
// COM
case 0x03: output += this.Address_direct("COM"); break; // COM (direct)
case 0x43: output += "\tCOMA\t"; break; // COM (COMA inherent)
case 0x53: output += "\tCOMB\t"; break; // COM (COMB inherent)
case 0x63: output += this.Address_indexed("COM"); break; // COM (indexed)
case 0x73: output += this.Address_extended("COM"); break; // COM (extended)
// CWAI
case 0x3c: output += this.Address_direct("CWAI"); break; // CWAI (direct)
// DAA
case 0x19: output += "\tDAA"; break; // DAA (inherent)
// DEC
case 0x0a: output += this.Address_direct("DEC"); break; // DEC (direct)
case 0x4a: output += "\tDECA\t"; break; // DEC (DECA inherent)
case 0x5a: output += "\tDECB\t"; break; // DEC (DECB inherent)
case 0x6a: output += this.Address_indexed("DEC"); break; // DEC (indexed)
case 0x7a: output += this.Address_extended("DEC"); break; // DEC (extended)
// EOR
// EORA
case 0x88: output += this.AM_immediate_byte("EORA"); break; // EOR (EORA immediate)
case 0x98: output += this.Address_direct("EORA"); break; // EOR (EORA direct)
case 0xa8: output += this.Address_indexed("EORA"); break; // EOR (EORA indexed)
case 0xb8: output += this.Address_extended("EORA"); break; // EOR (EORA extended)
// EORB
case 0xc8: output += this.AM_immediate_byte("EORB"); break; // EOR (EORB immediate)
case 0xd8: output += this.Address_direct("EORB"); break; // EOR (EORB direct)
case 0xe8: output += this.Address_indexed("EORB"); break; // EOR (EORB indexed)
case 0xf8: output += this.Address_extended("EORB"); break; // EOR (EORB extended)
// EXG
case 0x1e: output += this.TFR("EXG"); break; // EXG (R1,R2 immediate)
// INC
case 0x0c: output += this.Address_direct("INC"); break; // INC (direct)
case 0x4c: output += "\tINCA\t"; break; // INC (INCA inherent)
case 0x5c: output += "\tINCB\t"; break; // INC (INCB inherent)
case 0x6c: output += this.Address_indexed("INC"); break; // INC (indexed)
case 0x7c: output += this.Address_extended("INC"); break; // INC (extended)
// JMP
case 0x0e: output += this.Address_direct("JMP"); break; // JMP (direct)
case 0x6e: output += this.Address_indexed("JMP"); break; // JMP (indexed)
case 0x7e: output += this.Address_extended("JMP"); break; // JMP (extended)
// JSR
case 0x9d: output += this.Address_direct("JSR"); break; // JSR (direct)
case 0xad: output += this.Address_indexed("JSR"); break; // JSR (indexed)
case 0xbd: output += this.Address_extended("JSR"); break; // JSR (extended)
// LD
// LDA
case 0x86: output += this.AM_immediate_byte("LDA"); break; // LD (LDA immediate)
case 0x96: output += this.Address_direct("LDA"); break; // LD (LDA direct)
case 0xa6: output += this.Address_indexed("LDA"); break; // LD (LDA indexed)
case 0xb6: output += this.Address_extended("LDA"); break; // LD (LDA extended)
// LDB
case 0xc6: output += this.AM_immediate_byte("LDB"); break; // LD (LDB immediate)
case 0xd6: output += this.Address_direct("LDB"); break; // LD (LDB direct)
case 0xe6: output += this.Address_indexed("LDB"); break; // LD (LDB indexed)
case 0xf6: output += this.Address_extended("LDB"); break; // LD (LDB extended)
// LDD
case 0xcc: output += this.AM_immediate_word("LDD"); break; // LD (LDD immediate)
case 0xdc: output += this.Address_direct("LDD"); break; // LD (LDD direct)
case 0xec: output += this.Address_indexed("LDD"); break; // LD (LDD indexed)
case 0xfc: output += this.Address_extended("LDD"); break; // LD (LDD extended)
// LDU
case 0xce: output += this.AM_immediate_word("LDU"); break; // LD (LDU immediate)
case 0xde: output += this.Address_direct("LDU"); break; // LD (LDU direct)
case 0xee: output += this.Address_indexed("LDU"); break; // LD (LDU indexed)
case 0xfe: output += this.Address_extended("LDU"); break; // LD (LDU extended)
// LDX
case 0x8e: output += this.AM_immediate_word("LDX"); break; // LD (LDX immediate)
case 0x9e: output += this.Address_direct("LDX"); break; // LD (LDX direct)
case 0xae: output += this.Address_indexed("LDX"); break; // LD (LDX indexed)
case 0xbe: output += this.Address_extended("LDX"); break; // LD (LDX extended)
// LEA
case 0x30: output += this.Address_indexed("LEAX"); break; // LEA (LEAX indexed)
case 0x31: output += this.Address_indexed("LEAY"); break; // LEA (LEAY indexed)
case 0x32: output += this.Address_indexed("LEAS"); break; // LEA (LEAS indexed)
case 0x33: output += this.Address_indexed("LEAU"); break; // LEA (LEAU indexed)
// LSR
case 0x04: output += this.Address_direct("LSR"); break; // LSR (direct)
case 0x44: output += "\tLSRA\t"; break; // LSR (LSRA inherent)
case 0x54: output += "\tLSRB\t"; break; // LSR (LSRB inherent)
case 0x64: output += this.Address_indexed("LSR"); break; // LSR (indexed)
case 0x74: output += this.Address_extended("LSR"); break; // LSR (extended)
// MUL
case 0x3d: output += "\tMUL\t"; break; // MUL (inherent)
// NEG
case 0x00: output += this.Address_direct("NEG"); break; // NEG (direct)
case 0x40: output += "\tNEGA\t"; break; // NEG (NEGA, inherent)
case 0x50: output += "\tNEGB\t"; break; // NEG (NEGB, inherent)
case 0x60: output += this.Address_indexed("NEG"); break; // NEG (indexed)
case 0x70: output += this.Address_extended("NEG"); break; // NEG (extended)
// NOP
case 0x12: output += "\tNOP\t"; break; // NOP (inherent)
// OR
// ORA
case 0x8a: output += this.AM_immediate_byte("ORA"); break; // OR (ORA immediate)
case 0x9a: output += this.Address_direct("ORA"); break; // OR (ORA direct)
case 0xaa: output += this.Address_indexed("ORA"); break; // OR (ORA indexed)
case 0xba: output += this.Address_extended("ORA"); break; // OR (ORA extended)
// ORB
case 0xca: output += this.AM_immediate_byte("ORB"); break; // OR (ORB immediate)
case 0xda: output += this.Address_direct("ORB"); break; // OR (ORB direct)
case 0xea: output += this.Address_indexed("ORB"); break; // OR (ORB indexed)
case 0xfa: output += this.Address_extended("ORB"); break; // OR (ORB extended)
// ORCC
case 0x1a: output += this.AM_immediate_byte("ORCC"); break; // OR (ORCC immediate)
// PSH
case 0x34: output += this.PshS(); break; // PSH (PSHS immediate)
case 0x36: output += this.PshU(); break; // PSH (PSHU immediate)
// PUL
case 0x35: output += this.PulS(); break; // PUL (PULS immediate)
case 0x37: output += this.PulU(); break; // PUL (PULU immediate)
// ROL
case 0x09: output += this.Address_direct("ROL"); break; // ROL (direct)
case 0x49: output += "\tROLA\t"; break; // ROL (ROLA inherent)
case 0x59: output += "\tROLB\t"; break; // ROL (ROLB inherent)
case 0x69: output += this.Address_indexed("ROL"); break; // ROL (indexed)
case 0x79: output += this.Address_extended("ROL"); break; // ROL (extended)
// ROR
case 0x06: output += this.Address_direct("ROR"); break; // ROR (direct)
case 0x46: output += "\tRORA\t"; break; // ROR (RORA inherent)
case 0x56: output += "\tRORB\t"; break; // ROR (RORB inherent)
case 0x66: output += this.Address_indexed("ROR"); break; // ROR (indexed)
case 0x76: output += this.Address_extended("ROR"); break; // ROR (extended)
// RTI
case 0x3B: output += "\tRTI\t"; break; // RTI (inherent)
// RTS
case 0x39: output += "\tRTS\t"; break; // RTS (inherent)
// SBC
// SBCA
case 0x82: output += this.AM_immediate_byte("SBCA"); break; // SBC (SBCA immediate)
case 0x92: output += this.Address_direct("SBCA"); break; // SBC (SBCA direct)
case 0xa2: output += this.Address_indexed("SBCA"); break; // SBC (SBCA indexed)
case 0xb2: output += this.Address_extended("SBCA"); break; // SBC (SBCA extended)
// SBCB
case 0xc2: output += this.AM_immediate_byte("SBCB"); break; // SBC (SBCB immediate)
case 0xd2: output += this.Address_direct("SBCB"); break; // SBC (SBCB direct)
case 0xe2: output += this.Address_indexed("SBCB"); break; // SBC (SBCB indexed)
case 0xf2: output += this.Address_extended("SBCB"); break; // SBC (SBCB extended)
// SEX
case 0x1d: output += "\tSEX\t"; break; // SEX (inherent)
// ST
// STA
case 0x97: output += this.Address_direct("STA"); break; // ST (STA direct)
case 0xa7: output += this.Address_indexed("STA"); break; // ST (STA indexed)
case 0xb7: output += this.Address_extended("STA"); break; // ST (STA extended)
// STB
case 0xd7: output += this.Address_direct("STB"); break; // ST (STB direct)
case 0xe7: output += this.Address_indexed("STB"); break; // ST (STB indexed)
case 0xf7: output += this.Address_extended("STB"); break; // ST (STB extended)
// STD
case 0xdd: output += this.Address_direct("STD"); break; // ST (STD direct)
case 0xed: output += this.Address_indexed("STD"); break; // ST (STD indexed)
case 0xfd: output += this.Address_extended("STD"); break; // ST (STD extended)
// STU
case 0xdf: output += this.Address_direct("STU"); break; // ST (STU direct)
case 0xef: output += this.Address_indexed("STU"); break; // ST (STU indexed)
case 0xff: output += this.Address_extended("STU"); break; // ST (STU extended)
// STX
case 0x9f: output += this.Address_direct("STX"); break; // ST (STX direct)
case 0xaf: output += this.Address_indexed("STX"); break; // ST (STX indexed)
case 0xbf: output += this.Address_extended("STX"); break; // ST (STX extended)
// SUB
// SUBA
case 0x80: output += this.AM_immediate_byte("SUBA"); break; // SUB (SUBA immediate)
case 0x90: output += this.Address_direct("SUBA"); break; // SUB (SUBA direct)
case 0xa0: output += this.Address_indexed("SUBA"); break; // SUB (SUBA indexed)
case 0xb0: output += this.Address_extended("SUBA"); break; // SUB (SUBA extended)
// SUBB
case 0xc0: output += this.AM_immediate_byte("SUBB"); break; // SUB (SUBB immediate)
case 0xd0: output += this.Address_direct("SUBB"); break; // SUB (SUBB direct)
case 0xe0: output += this.Address_indexed("SUBB"); break; // SUB (SUBB indexed)
case 0xf0: output += this.Address_extended("SUBB"); break; // SUB (SUBB extended)
// SUBD
case 0x83: output += this.AM_immediate_word("SUBD"); break; // SUB (SUBD immediate)
case 0x93: output += this.Address_direct("SUBD"); break; // SUB (SUBD direct)
case 0xa3: output += this.Address_indexed("SUBD"); break; // SUB (SUBD indexed)
case 0xb3: output += this.Address_extended("SUBD"); break; // SUB (SUBD extended)
// SWI
case 0x3f: output += "\tSWI\t"; break; // SWI (inherent)
// SYNC
case 0x13: output += "\tSYNC\t"; break; // SYNC (inherent)
// TFR
case 0x1f: output += this.TFR("TFR"); break; // TFR (immediate)
// TST
case 0x0d: output += this.Address_direct("TST"); break; // TST (direct)
case 0x4d: output += "\tTSTA\t"; break; // TST (TSTA inherent)
case 0x5d: output += "\tTSTB\t"; break; // TST (TSTB inherent)
case 0x6d: output += this.Address_indexed("TST"); break; // TST (indexed)
case 0x7d: output += this.Address_extended("TST"); break; // TST (extended)
// Branching
case 0x16: output += this.BranchLong("LBRA"); break; // BRA (LBRA relative)
case 0x17: output += this.BranchLong("LBSR"); break; // BSR (LBSR relative)
case 0x20: output += this.BranchShort("BRA"); break; // BRA (relative)
case 0x21: output += this.BranchShort("BRN"); break; // BRN (relative)
case 0x22: output += this.BranchShort("BHI"); break; // BHI (relative)
case 0x23: output += this.BranchShort("BLS"); break; // BLS (relative)
case 0x24: output += this.BranchShort("BCC"); break; // BCC (relative)
case 0x25: output += this.BranchShort("BCS"); break; // BCS (relative)
case 0x26: output += this.BranchShort("BNE"); break; // BNE (relative)
case 0x27: output += this.BranchShort("BEQ"); break; // BEQ (relative)
case 0x28: output += this.BranchShort("BVC"); break; // BVC (relative)
case 0x29: output += this.BranchShort("BVS"); break; // BVS (relative)
case 0x2a: output += this.BranchShort("BPL"); break; // BPL (relative)
case 0x2b: output += this.BranchShort("BMI"); break; // BMI (relative)
case 0x2c: output += this.BranchShort("BGE"); break; // BGE (relative)
case 0x2d: output += this.BranchShort("BLT"); break; // BLT (relative)
case 0x2e: output += this.BranchShort("BGT"); break; // BGT (relative)
case 0x2f: output += this.BranchShort("BLE"); break; // BLE (relative)
case 0x8d: output += this.BranchShort("BSR"); break; // BSR (relative)
default:
throw new InvalidOperationException("Unknown opcode");
}
return output;
}
private string Disassemble10()
{
var opcode = this.GetByte(this.address);
var output = $"{opcode:x2}";
switch (opcode)
{
// CMP
// CMPD
case 0x83: output += this.AM_immediate_word("CMPD"); break; // CMP (CMPD, immediate)
case 0x93: output += this.Address_direct("CMPD"); break; // CMP (CMPD, direct)
case 0xa3: output += this.Address_indexed("CMPD"); break; // CMP (CMPD, indexed)
case 0xb3: output += this.Address_extended("CMPD"); break; // CMP (CMPD, extended)
// CMPY
case 0x8c: output += this.AM_immediate_word("CMPY"); break; // CMP (CMPY, immediate)
case 0x9c: output += this.Address_direct("CMPY"); break; // CMP (CMPY, direct)
case 0xac: output += this.Address_indexed("CMPY"); break; // CMP (CMPY, indexed)
case 0xbc: output += this.Address_extended("CMPY"); break; // CMP (CMPY, extended)
// LD
// LDS
case 0xce: output += this.AM_immediate_word("LDS"); break; // LD (LDS immediate)
case 0xde: output += this.Address_direct("LDS"); break; // LD (LDS direct)
case 0xee: output += this.Address_indexed("LDS"); break; // LD (LDS indexed)
case 0xfe: output += this.Address_extended("LDS"); break; // LD (LDS extended)
// LDY
case 0x8e: output += this.AM_immediate_word("LDY"); break; // LD (LDY immediate)
case 0x9e: output += this.Address_direct("LDY"); break; // LD (LDY direct)
case 0xae: output += this.Address_indexed("LDY"); break; // LD (LDY indexed)
case 0xbe: output += this.Address_extended("LDY"); break; // LD (LDY extended)
// Branching
case 0x21: output += this.BranchLong("LBRN"); break; // BRN (LBRN relative)
case 0x22: output += this.BranchLong("LBHI"); break; // BHI (LBHI relative)
case 0x23: output += this.BranchLong("LBLS"); break; // BLS (LBLS relative)
case 0x24: output += this.BranchLong("LBCC"); break; // BCC (LBCC relative)
case 0x25: output += this.BranchLong("LBCS"); break; // BCS (LBCS relative)
case 0x26: output += this.BranchLong("LBNE"); break; // BNE (LBNE relative)
case 0x27: output += this.BranchLong("LBEQ"); break; // BEQ (LBEQ relative)
case 0x28: output += this.BranchLong("LBVC"); break; // BVC (LBVC relative)
case 0x29: output += this.BranchLong("LBVS"); break; // BVS (LBVS relative)
case 0x2a: output += this.BranchLong("LBPL"); break; // BPL (LBPL relative)
case 0x2b: output += this.BranchLong("LBMI"); break; // BMI (LBMI relative)
case 0x2c: output += this.BranchLong("LBGE"); break; // BGE (LBGE relative)
case 0x2d: output += this.BranchLong("LBLT"); break; // BLT (LBLT relative)
case 0x2e: output += this.BranchLong("LBGT"); break; // BGT (LBGT relative)
case 0x2f: output += this.BranchLong("LBLE"); break; // BLE (LBLE relative)
// STS
case 0xdf: output += this.Address_direct("STS"); break; // ST (STS direct)
case 0xef: output += this.Address_indexed("STS"); break; // ST (STS indexed)
case 0xff: output += this.Address_extended("STS"); break; // ST (STS extended)
// STY
case 0x9f: output += this.Address_direct("STY"); break; // ST (STY direct)
case 0xaf: output += this.Address_indexed("STY"); break; // ST (STY indexed)
case 0xbf: output += this.Address_extended("STY"); break; // ST (STY extended)
// SWI
case 0x3f: output += "\tSWI2\t"; break; // SWI (SWI2 inherent)
default:
throw new InvalidOperationException("Unknown group 10 opcode");
}
this.prefix10 = false;
return output;
}
private string Disassemble11()
{
var opcode = this.GetByte(this.address);
var output = $"{opcode:x2}";
switch (opcode)
{
// CMP
// CMPU
case 0x83: output += this.AM_immediate_word("CMPU"); break; // CMP (CMPU, immediate)
case 0x93: output += this.Address_direct("CMPU"); break; // CMP (CMPU, direct)
case 0xa3: output += this.Address_indexed("CMPU"); break; // CMP (CMPU, indexed)
case 0xb3: output += this.Address_extended("CMPU"); break; // CMP (CMPU, extended)
// CMPS
case 0x8c: output += this.AM_immediate_word("CMPS"); break; // CMP (CMPS, immediate)
case 0x9c: output += this.Address_direct("CMPS"); break; // CMP (CMPS, direct)
case 0xac: output += this.Address_indexed("CMPS"); break; // CMP (CMPS, indexed)
case 0xbc: output += this.Address_extended("CMPS"); break; // CMP (CMPS, extended)
// SWI
case 0x3f: output += "\tSWI3\t"; break; // SWI (SWI3 inherent)
default:
throw new InvalidOperationException("Unknown group 11 opcode");
}
this.prefix11 = false;
return output;
}
////
private string Address_direct(string mnemomic)
{
var offset = this.GetByte(++this.address);
return $"{offset:x2}\t{mnemomic}\t${offset:x2}";
}
private string Address_indexed(string mnemomic)
{
var type = this.GetByte(++this.address);
var r = RR((type & (byte)(Bits.Bit6 | Bits.Bit5)) >> 5);
byte byte8 = 0xff;
ushort word = 0xffff;
var output = $"{type:x2}";
if ((type & (byte)Bits.Bit7) != 0)
{
var indirect = (type & (byte)Bits.Bit4) != 0;
switch (type & (byte)Mask.Four)
{
case 0b0000: // ,R+
output += $"\t{mnemomic}\t{WrapIndirect($",{r}+", indirect)}";
break;
case 0b0001: // ,R++
output += $"\t{mnemomic}\t{WrapIndirect($",{r}++", indirect)}";
break;
case 0b0010: // ,-R
output += $"\t{mnemomic}\t{WrapIndirect($",-{r}", indirect)}";
break;
case 0b0011: // ,--R
output += $"\t{mnemomic}\t{WrapIndirect($",--{r}", indirect)}";
break;
case 0b0100: // ,R
output += $"\t{mnemomic}\t{WrapIndirect($",{r}", indirect)}";
break;
case 0b0101: // B,R
output += $"\t{mnemomic}\t{WrapIndirect($"B,{r}", indirect)}";
break;
case 0b0110: // A,R
output += $"\t{mnemomic}\t{WrapIndirect($"A,{r}", indirect)}";
break;
case 0b1000: // n,R (eight-bit)
byte8 = this.GetByte(++this.address);
output += $"{byte8:x2}\t{mnemomic}\t{WrapIndirect($"{byte8:x2},{r}", indirect)}";
break;
case 0b1001: // n,R (sixteen-bit)
word = this.GetWord(++this.address);
output += $"{word:x4}\t{mnemomic}\t{WrapIndirect($"{word:x4},{r}", indirect)}";
break;
case 0b1011: // D,R
output += $"\t{mnemomic}\t{WrapIndirect($"D,{r}", indirect)}";
break;
case 0b1100: // n,PCR (eight-bit)
byte8 = this.GetByte(++this.address);
output += $"{byte8:x2}\t{mnemomic}\t{WrapIndirect("${(byte)byte8:D},PCR", indirect)}";
break;
case 0b1101: // n,PCR (sixteen-bit)
word = this.GetWord(++this.address);
output += $"{word:x4}\t{mnemomic}\t{WrapIndirect("${(short)word:D},PCR", indirect)}";
break;
case 0b1111: // [n]
if (!indirect)
{
throw new InvalidOperationException("Index specification cannot be direct");
}
word = this.GetWord(++this.address);
output += $"{word:x4}\t{mnemomic}\t{WrapIndirect("${word:x4}", indirect)}";
break;
default:
throw new InvalidOperationException("Invalid index specification used");
}
}
else
{
// EA = ,R + 5-bit offset
output += $"\t{mnemomic}\t{Processor.SignExtend(5, type & (byte)Mask.Five)},{r}";
}
return output;
}
private string Address_extended(string mnemomic)
{
var word = this.GetWord(++this.address);
return $"{word:x4}\t{mnemomic}\t${word:x4}";
}
private string Address_relative_byte(string mnemomic)
{
var byte8 = this.GetByte(++this.address);
return $"{byte8:x2}\t{mnemomic}\t${++this.address + (sbyte)byte8:x4}";
}
private string Address_relative_word(string mnemomic)
{
var word = this.GetWord(++this.address);
return $"{word:x4}\t{mnemomic}\t${++this.address + (short)word:x4}";
}
private string AM_immediate_byte(string mnemomic)
{
var byte8 = this.GetByte(++this.address);
return $"{byte8:x2}\t{mnemomic}\t#${byte8:x2}";
}
private string AM_immediate_word(string mnemomic)
{
var word = this.GetWord(++this.address);
return $"{word:x4}\t{mnemomic}\t#${word:x4}";
}
private string BranchShort(string mnemomic) => this.Address_relative_byte(mnemomic);
private string BranchLong(string mnemomic) => this.Address_relative_word(mnemomic);
private string TFR(string mnemomic)
{
var data = this.GetByte(++this.address);
var reg1 = Chip.HighNibble(data);
var reg2 = Chip.LowNibble(data);
var output = $"{data:x2}\t{mnemomic}\t";
var type8 = (reg1 & (byte)Bits.Bit3) != 0; // 8 bit?
return type8
? $"{output}{ReferenceTransfer8(reg1)},{ReferenceTransfer8(reg2)}"
: $"{output}{ReferenceTransfer16(reg1)},{ReferenceTransfer16(reg2)}";
}
////
private string PulS() => this.PulX("PULS", "U");
private string PulU() => this.PulX("PULU", "S");
private string PshS() => this.PshX("PSHS", "U");
private string PshU() => this.PshX("PSHU", "S");
private string PulX(string mnemomic, string upon)
{
var data = this.GetByte(++this.address);
var output = $"{data:x2}\t{mnemomic}\t";
var registers = new List();
if ((data & (byte)Bits.Bit0) != 0)
{
registers.Add("CC");
}
if ((data & (byte)Bits.Bit1) != 0)
{
registers.Add("A");
}
if ((data & (byte)Bits.Bit2) != 0)
{
registers.Add("B");
}
if ((data & (byte)Bits.Bit3) != 0)
{
registers.Add("DP");
}
if ((data & (byte)Bits.Bit4) != 0)
{
registers.Add("X");
}
if ((data & (byte)Bits.Bit5) != 0)
{
registers.Add("Y");
}
if ((data & (byte)Bits.Bit6) != 0)
{
registers.Add(upon);
}
if ((data & (byte)Bits.Bit7) != 0)
{
registers.Add("PC");
}
return output + string.Join(",", registers);
}
private string PshX(string mnemomic, string upon)
{
var data = this.GetByte(++this.address);
var output = $"{data:x2}\t{mnemomic}\t";
var registers = new List();
if ((data & (byte)Bits.Bit7) != 0)
{
registers.Add("PC");
}
if ((data & (byte)Bits.Bit6) != 0)
{
registers.Add(upon);
}
if ((data & (byte)Bits.Bit5) != 0)
{
registers.Add("Y");
}
if ((data & (byte)Bits.Bit4) != 0)
{
registers.Add("X");
}
if ((data & (byte)Bits.Bit3) != 0)
{
registers.Add("DP");
}
if ((data & (byte)Bits.Bit2) != 0)
{
registers.Add("B");
}
if ((data & (byte)Bits.Bit1) != 0)
{
registers.Add("A");
}
if ((data & (byte)Bits.Bit0) != 0)
{
registers.Add("CC");
}
return output + string.Join(",", registers);
}
private byte GetByte(ushort absolute) => this.BUS.Peek(absolute);
private ushort GetWord(ushort absolute) => this.CPU.PeekWord(absolute).Word;
}
}