using System; namespace BizHawk.Emulation.Common.Components.MC6800 { public partial class MC6800 { public ulong TotalExecutedCycles; // variables for executing instructions public int instr_pntr = 0; public ushort[] cur_instr = new ushort[60]; public int opcode_see; public int IRQS; public int irq_pntr; ushort reg_d_ad; ushort reg_h_ad; ushort reg_l_ad; public void FetchInstruction(byte opcode) { opcode_see = opcode; switch (opcode) { case 0x00: ILLEGAL(); break; // ILLEGAL case 0x01: NOP_(); break; // NOP (Inherent) case 0x02: ILLEGAL(); break; // ILLEGAL case 0x03: ILLEGAL(); break; // ILLEGAL case 0x04: ILLEGAL(); break; // ILLEGAL case 0x05: ILLEGAL(); break; // ILLEGAL case 0x06: REG_OP(TAP, A); break; // TAP (Inherent) case 0x07: REG_OP(TPA, A); break; // TPA (Inherent) case 0x08: REG_OP_16(INX, X); break; // INX (Inherent) case 0x09: REG_OP_16(DEX, X); break; // DEX (Inherent) case 0x0A: REG_OP(CLV, CC); break; // CLV (Inherent) case 0x0B: REG_OP(SEV, CC); break; // SEV (Inherent) case 0x0C: REG_OP(CLC, CC); break; // CLC (Inherent) case 0x0D: REG_OP(SEC, CC); break; // SEC (Inherent) case 0x0E: REG_OP(CLI, CC); break; // CLI (Inherent) case 0x0F: REG_OP(SEI, CC); break; // SEI (Inherent) case 0x10: REG_OP(SBA, A); break; // SBA (Inherent) case 0x11: REG_OP(CBA, A); break; // CBA (Inherent) case 0x12: ILLEGAL(); break; // ILLEGAL case 0x13: ILLEGAL(); break; // ILLEGAL case 0x14: ILLEGAL(); break; // ILLEGAL case 0x15: ILLEGAL(); break; // ILLEGAL case 0x16: REG_OP(TAB, A); break; // TAB (Inherent) case 0x17: REG_OP(TBA, A); break; // TBA (Inherent) case 0x18: ILLEGAL(); break; // ILLEGAL case 0x19: REG_OP(DA, A); break; // DAA (Inherent) case 0x1A: ILLEGAL(); break; // ILLEGAL case 0x1B: REG_OP(ABA, A); break; // ABA (Inherent) case 0x1C: ILLEGAL(); break; // ILLEGAL case 0x1D: ILLEGAL(); break; // ILLEGAL case 0x1E: ILLEGAL(); break; // ILLEGAL case 0x1F: ILLEGAL(); break; // ILLEGAL case 0x20: BR_(true); break; // BRA (Relative) case 0x21: ILLEGAL(); break; // ILLEGAL case 0x22: BR_(!(FlagC | FlagZ)); break; // BHI (Relative) case 0x23: BR_(FlagC | FlagZ); break; // BLS (Relative) case 0x24: BR_(!FlagC); break; // BHS , BCC (Relative) case 0x25: BR_(FlagC); break; // BLO , BCS (Relative) case 0x26: BR_(!FlagZ); break; // BNE (Relative) case 0x27: BR_(FlagZ); break; // BEQ (Relative) case 0x28: BR_(!FlagV); break; // BVC (Relative) case 0x29: BR_(FlagV); break; // BVS (Relative) case 0x2A: BR_(!FlagN); break; // BPL (Relative) case 0x2B: BR_(FlagN); break; // BMI (Relative) case 0x2C: BR_(FlagN == FlagV); break; // BGE (Relative) case 0x2D: BR_(FlagN ^ FlagV); break; // BLT (Relative) case 0x2E: BR_((!FlagZ) & (FlagN == FlagV)); break; // BGT (Relative) case 0x2F: BR_(FlagZ | (FlagN ^ FlagV)); break; // BLE (Relative) case 0x30: REG_OP_16(TSX, X); break; // TSX (Inherent) case 0x31: REG_OP_16(INS, SP); break; // INS (Inherent) case 0x32: PUL_(A); break; // PULA (Inherent) case 0x33: PUL_(B); break; // PULB (Inherent) case 0x34: REG_OP_16(DES, SP); break; // DES (Inherent) case 0x35: REG_OP_16(TXS, SP); break; // TXS (Inherent) case 0x36: PSH_(A); break; // PSHA (Inherent) case 0x37: PSH_(B); break; // PSHB (Inherent) case 0x38: ILLEGAL(); break; // ILLEGAL case 0x39: RTS(); break; // RTS (Inherent) case 0x3A: ILLEGAL(); break; // ILLEGAL case 0x3B: RTI(); break; // RTI (Inherent) case 0x3C: ILLEGAL(); break; // ILLEGAL case 0x3D: ILLEGAL(); break; // ILLEGAL case 0x3E: WAI_(); break; // WAI (Inherent) case 0x3F: SWI1(); break; // SWI (Inherent) case 0x40: REG_OP(NEG, A); break; // NEGA (Inherent) case 0x41: ILLEGAL(); break; // ILLEGAL case 0x42: ILLEGAL(); break; // ILLEGAL case 0x43: REG_OP(COM, A); break; // COMA (Inherent) case 0x44: REG_OP(LSR, A); break; // LSRA (Inherent) case 0x45: ILLEGAL(); break; // ILLEGAL case 0x46: REG_OP(ROR, A); break; // RORA (Inherent) case 0x47: REG_OP(ASR, A); break; // ASRA (Inherent) case 0x48: REG_OP(ASL, A); break; // ASLA , LSLA (Inherent) case 0x49: REG_OP(ROL, A); break; // ROLA (Inherent) case 0x4A: REG_OP(DEC8, A); break; // DECA (Inherent) case 0x4B: ILLEGAL(); break; // ILLEGAL case 0x4C: REG_OP(INC8, A); break; // INCA (Inherent) case 0x4D: REG_OP(TST, A); break; // TSTA (Inherent) case 0x4E: ILLEGAL(); break; // ILLEGAL case 0x4F: REG_OP(CLR, A); break; // CLRA (Inherent) case 0x50: REG_OP(NEG, B); break; // NEGB (Inherent) case 0x51: ILLEGAL(); break; // ILLEGAL case 0x52: ILLEGAL(); break; // ILLEGAL case 0x53: REG_OP(COM, B); break; // COMB (Inherent) case 0x54: REG_OP(LSR, B); break; // LSRB (Inherent) case 0x55: ILLEGAL(); break; // ILLEGAL case 0x56: REG_OP(ROR, B); break; // RORB (Inherent) case 0x57: REG_OP(ASR, B); break; // ASRB (Inherent) case 0x58: REG_OP(ASL, B); break; // ASLB , LSLB (Inherent) case 0x59: REG_OP(ROL, B); break; // ROLB (Inherent) case 0x5A: REG_OP(DEC8, B); break; // DECB (Inherent) case 0x5B: ILLEGAL(); break; // ILLEGAL case 0x5C: REG_OP(INC8, B); break; // INCB (Inherent) case 0x5D: REG_OP(TST, B); break; // TSTB (Inherent) case 0x5E: ILLEGAL(); break; // ILLEGAL case 0x5F: REG_OP(CLR, B); break; // CLRB (Inherent) case 0x60: INDEX_OP(I_NEG); break; // NEG (Indexed) case 0x61: ILLEGAL(); break; // ILLEGAL case 0x62: ILLEGAL(); break; // ILLEGAL case 0x63: INDEX_OP(I_COM); break; // COM (Indexed) case 0x64: INDEX_OP(I_LSR); break; // LSR (Indexed) case 0x65: ILLEGAL(); break; // ILLEGAL case 0x66: INDEX_OP(I_ROR); break; // ROR (Indexed) case 0x67: INDEX_OP(I_ASR); break; // ASR (Indexed) case 0x68: INDEX_OP(I_ASL); break; // ASL , LSL (Indexed) case 0x69: INDEX_OP(I_ROL); break; // ROL (Indexed) case 0x6A: INDEX_OP(I_DEC); break; // DEC (Indexed) case 0x6B: ILLEGAL(); break; // ILLEGAL case 0x6C: INDEX_OP(I_INC); break; // INC (Indexed) case 0x6D: INDEX_OP(I_TST); break; // TST (Indexed) case 0x6E: INDEX_OP(I_JMP); break; // JMP (Indexed) case 0x6F: INDEX_OP(I_CLR); break; // CLR (Indexed) case 0x70: EXT_MEM(NEG); break; // NEG (Extended) case 0x71: ILLEGAL(); break; // ILLEGAL case 0x72: ILLEGAL(); break; // ILLEGAL case 0x73: EXT_MEM(COM); break; // COM (Extended) case 0x74: EXT_MEM(LSR); break; // LSR (Extended) case 0x75: ILLEGAL(); break; // ILLEGAL case 0x76: EXT_MEM(ROR); break; // ROR (Extended) case 0x77: EXT_MEM(ASR); break; // ASR (Extended) case 0x78: EXT_MEM(ASL); break; // ASL , LSL (Extended) case 0x79: EXT_MEM(ROL); break; // ROL (Extended) case 0x7A: EXT_MEM(DEC8); break; // DEC (Extended) case 0x7B: ILLEGAL(); break; // ILLEGAL case 0x7C: EXT_MEM(INC8); break; // INC (Extended) case 0x7D: EXT_MEM(TST); break; // TST (Extended) case 0x7E: JMP_EXT_(); break; // JMP (Extended) case 0x7F: EXT_MEM(CLR); break; // CLR (Extended) case 0x80: REG_OP_IMD(SUB8, A); break; // SUBA (Immediate) case 0x81: REG_OP_IMD(CMP8, A); break; // CMPA (Immediate) case 0x82: REG_OP_IMD(SBC8, A); break; // SBCA (Immediate) case 0x83: ILLEGAL(); break; // ILLEGAL case 0x84: REG_OP_IMD(AND8, A); break; // ANDA (Immediate) case 0x85: REG_OP_IMD(BIT, A); break; // BITA (Immediate) case 0x86: REG_OP_IMD(LD_8, A); break; // LDA (Immediate) case 0x87: ILLEGAL(); break; // ILLEGAL case 0x88: REG_OP_IMD(XOR8, A); break; // EORA (Immediate) case 0x89: REG_OP_IMD(ADC8, A); break; // ADCA (Immediate) case 0x8A: REG_OP_IMD(OR8, A); break; // ORA (Immediate) case 0x8B: REG_OP_IMD(ADD8, A); break; // ADDA (Immediate) case 0x8C: IMD_CMP_16(CMP16, X); break; // CMPX (Immediate) case 0x8D: BSR_(); break; // BSR (Relative) case 0x8E: REG_OP_LD_16(SP); break; // LDS (Immediate) case 0x8F: ILLEGAL(); break; // ILLEGAL case 0x90: DIRECT_MEM_4(SUB8, A); break; // SUBA (Direct) case 0x91: DIRECT_MEM_4(CMP8, A); break; // CMPA (Direct) case 0x92: DIRECT_MEM_4(SBC8, A); break; // SBCA (Direct) case 0x93: ILLEGAL(); break; // ILLEGAL case 0x94: DIRECT_MEM_4(AND8, A); break; // ANDA (Direct) case 0x95: DIRECT_MEM_4(BIT, A); break; // BITA (Direct) case 0x96: DIRECT_MEM_4(LD_8, A); break; // LDA (Direct) case 0x97: DIRECT_ST_4(A); break; // STA (Direct) case 0x98: DIRECT_MEM_4(XOR8, A); break; // EORA (Direct) case 0x99: DIRECT_MEM_4(ADC8, A); break; // ADCA (Direct) case 0x9A: DIRECT_MEM_4(OR8, A); break; // ORA (Direct) case 0x9B: DIRECT_MEM_4(ADD8, A); break; // ADDA (Direct) case 0x9C: DIR_CMP_16(CMP16, X); break; // CMPX (Direct) case 0x9D: ILLEGAL(); break; // ILLEGAL case 0x9E: DIR_OP_LD_16(SP); break; // LDS (Direct) case 0x9F: DIR_OP_ST_16(SP); break; // STS (Direct) case 0xA0: INDEX_OP_REG(I_SUB, A); break; // SUBA (Indexed) case 0xA1: INDEX_OP_REG(I_CMP, A); break; // CMPA (Indexed) case 0xA2: INDEX_OP_REG(I_SBC, A); break; // SBCA (Indexed) case 0xA3: ILLEGAL(); break; // ILLEGAL case 0xA4: INDEX_OP_REG(I_AND, A); break; // ANDA (Indexed) case 0xA5: INDEX_OP_REG(I_BIT, A); break; // BITA (Indexed) case 0xA6: INDEX_OP_REG(I_LD, A); break; // LDA (Indexed) case 0xA7: INDEX_OP_REG(I_ST, A); break; // STA (Indexed) case 0xA8: INDEX_OP_REG(I_XOR, A); break; // EORA (Indexed) case 0xA9: INDEX_OP_REG(I_ADC, A); break; // ADCA (Indexed) case 0xAA: INDEX_OP_REG(I_OR, A); break; // ORA (Indexed) case 0xAB: INDEX_OP_REG(I_ADD, A); break; // ADDA (Indexed) case 0xAC: INDEX_OP_REG(I_CMP16, X); break; // CMPX (Indexed) case 0xAD: INDEX_OP(I_JSR); break; // JSR (Indexed) case 0xAE: INDEX_OP_REG(I_LD16, SP); break; // LDS (Indexed) case 0xAF: INDEX_OP_REG(I_ST16, SP); break; // STS (Indexed) case 0xB0: EXT_REG(SUB8, A); break; // SUBA (Extended) case 0xB1: EXT_REG(CMP8, A); break; // CMPA (Extended) case 0xB2: EXT_REG(SBC8, A); break; // SBCA (Extended) case 0xB3: ILLEGAL(); break; // ILLEGAL case 0xB4: EXT_REG(AND8, A); break; // ANDA (Extended) case 0xB5: EXT_REG(BIT, A); break; // BITA (Extended) case 0xB6: EXT_REG(LD_8, A); break; // LDA (Extended) case 0xB7: EXT_ST(A); break; // STA (Extended) case 0xB8: EXT_REG(XOR8, A); break; // EORA (Extended) case 0xB9: EXT_REG(ADC8, A); break; // ADCA (Extended) case 0xBA: EXT_REG(OR8, A); break; // ORA (Extended) case 0xBB: EXT_REG(ADD8, A); break; // ADDA (Extended) case 0xBC: EXT_CMP_16(CMP16, X); break; // CMPX (Extended) case 0xBD: JSR_EXT(); break; // JSR (Extended) case 0xBE: EXT_OP_LD_16(SP); break; // LDS (Extended) case 0xBF: EXT_OP_ST_16(SP); break; // STS (Extended) case 0xC0: REG_OP_IMD(SUB8, B); break; // SUBB (Immediate) case 0xC1: REG_OP_IMD(CMP8, B); break; // CMPB (Immediate) case 0xC2: REG_OP_IMD(SBC8, B); break; // SBCB (Immediate) case 0xC3: ILLEGAL(); break; // ILLEGAL case 0xC4: REG_OP_IMD(AND8, B); break; // ANDB (Immediate) case 0xC5: REG_OP_IMD(BIT, B); break; // BITB (Immediate) case 0xC6: REG_OP_IMD(LD_8, B); break; // LDB (Immediate) case 0xC7: ILLEGAL(); break; // ILLEGAL case 0xC8: REG_OP_IMD(XOR8, B); break; // EORB (Immediate) case 0xC9: REG_OP_IMD(ADC8, B); break; // ADCB (Immediate) case 0xCA: REG_OP_IMD(OR8, B); break; // ORB (Immediate) case 0xCB: REG_OP_IMD(ADD8, B); break; // ADDB (Immediate) case 0xCC: ILLEGAL(); break; // ILLEGAL case 0xCD: ILLEGAL(); break; // ILLEGAL case 0xCE: REG_OP_LD_16(X); break; // LDX (Immediate) case 0xCF: ILLEGAL(); break; // ILLEGAL case 0xD0: DIRECT_MEM_4(SUB8, B); break; // SUBB (Direct) case 0xD1: DIRECT_MEM_4(CMP8, B); break; // CMPB (Direct) case 0xD2: DIRECT_MEM_4(SBC8, B); break; // SBCB (Direct) case 0xD3: ILLEGAL(); break; // ILLEGAL case 0xD4: DIRECT_MEM_4(AND8, B); break; // ANDB (Direct) case 0xD5: DIRECT_MEM_4(BIT, B); break; // BITB (Direct) case 0xD6: DIRECT_MEM_4(LD_8, B); break; // LDB (Direct) case 0xD7: DIRECT_ST_4(B); break; // STB (Direct) case 0xD8: DIRECT_MEM_4(XOR8, B); break; // EORB (Direct) case 0xD9: DIRECT_MEM_4(ADC8, B); break; // ADCB (Direct) case 0xDA: DIRECT_MEM_4(OR8, B); break; // ORB (Direct) case 0xDB: DIRECT_MEM_4(ADD8, B); break; // ADDB (Direct) case 0xDC: ILLEGAL(); break; // ILLEGAL case 0xDD: ILLEGAL(); break; // ILLEGAL case 0xDE: DIR_OP_LD_16(X); break; // LDX (Direct) case 0xDF: DIR_OP_ST_16(X); break; // STX (Direct) case 0xE0: INDEX_OP_REG(I_SUB, B); break; // SUBB (Indexed) case 0xE1: INDEX_OP_REG(I_CMP, B); break; // CMPB (Indexed) case 0xE2: INDEX_OP_REG(I_SBC, B); break; // SBCB (Indexed) case 0xE3: ILLEGAL(); break; // ILLEGAL case 0xE4: INDEX_OP_REG(I_AND, B); break; // ANDB (Indexed) case 0xE5: INDEX_OP_REG(I_BIT, B); break; // BITB (Indexed) case 0xE6: INDEX_OP_REG(I_LD, B); break; // LDB (Indexed) case 0xE7: INDEX_OP_REG(I_ST, B); break; // STB (Indexed) case 0xE8: INDEX_OP_REG(I_XOR, B); break; // EORB (Indexed) case 0xE9: INDEX_OP_REG(I_ADC, B); break; // ADCB (Indexed) case 0xEA: INDEX_OP_REG(I_OR, B); break; // ORB (Indexed) case 0xEB: INDEX_OP_REG(I_ADD, B); break; // ADDB (Indexed) case 0xEC: ILLEGAL(); break; // ILLEGAL case 0xED: ILLEGAL(); break; // ILLEGAL case 0xEE: INDEX_OP_REG(I_LD16, X); break; // LDX (Indexed) case 0xEF: INDEX_OP_REG(I_ST16, X); break; // STX (Indexed) case 0xF0: EXT_REG(SUB8, B); break; // SUBB (Extended) case 0xF1: EXT_REG(CMP8, B); break; // CMPB (Extended) case 0xF2: EXT_REG(SBC8, B); break; // SBCB (Extended) case 0xF3: ILLEGAL(); break; // ILLEGAL case 0xF4: EXT_REG(AND8, B); break; // ANDB (Extended) case 0xF5: EXT_REG(BIT, B); break; // BITB (Extended) case 0xF6: EXT_REG(LD_8, B); break; // LDB (Extended) case 0xF7: EXT_ST(B); break; // STB (Extended) case 0xF8: EXT_REG(XOR8, B); break; // EORB (Extended) case 0xF9: EXT_REG(ADC8, B); break; // ADCB (Extended) case 0xFA: EXT_REG(OR8, B); break; // ORB (Extended) case 0xFB: EXT_REG(ADD8, B); break; // ADDB (Extended) case 0xFC: ILLEGAL(); break; // ILLEGAL case 0xFD: ILLEGAL(); break; // ILLEGAL case 0xFE: EXT_OP_LD_16(X); break; // LDX (Extended) case 0xFF: EXT_OP_ST_16(X); break; // STX (Extended) } } } }