Beispiel #1
0
        private void Dispatch(byte op)
        {
            switch (op)
            {
            //nop;
            case 0:
                break;

            case 0xcb:
                DispatchCb();
                break;

            //LD(nn),sp
            case 0x8:
                mmu.WriteWord(NextWord(), Registers.SP);
                Cycles += OpTiming.LD_SP;
                break;

            //RLCA
            case 0x07:
                Registers.A = ControlUnit.RLCA(Registers.A);
                Cycles     += OpTiming.SHIFT;
                break;

            //RLA
            case 0x17:
                Registers.A = ControlUnit.RLA(Registers.A);
                Cycles     += OpTiming.SHIFT;
                break;

            case 0x10:
                throw new Exception("STOP");

            case 0x18:
            case 0x20:
            case 0x28:
            case 0x30:
            case 0x38:
                ControlUnit.Jr(op, (sbyte)NextByte());

                break;

            case 0x01:
            case 0x11:
            case 0x21:
            case 0x31:
                Registers.LoadWordRegisterPair1((op >> 4), NextWord());
                Cycles += OpTiming.LD_WORD;
                break;

            case 0x09:
            case 0x19:
            case 0x29:
            case 0x39:
                ControlUnit.Add16(Registers.ReadWordRegisterPair1(op >> 4));
                Cycles += OpTiming.ARITHMETIC_LOAD;
                break;

            //LD (BC), A
            case 0x02:
            case 0x12:
            case 0x22:
            case 0x32:
                WriteByte(Registers.ReadWordRegisterPair3(op >> 4), Registers.A);
                Cycles += OpTiming.STORE_BYTE;
                break;

            case 0xa:
            case 0x1a:
            case 0x2a:
            case 0x3a:
                Registers.A = Registers.RegisterPair2Indirect(op >> 4);
                Cycles     += OpTiming.STORE_BYTE;
                break;

            case 0x03:
                Registers.BC++;
                Cycles += OpTiming.INC_WORD_REG;
                break;

            case 0x13:
                Registers.DE++;
                Cycles += OpTiming.INC_WORD_REG;
                break;

            case 0x23:
                Registers.HL++;
                Cycles += OpTiming.INC_WORD_REG;
                break;

            case 0x33:
                Registers.SP++;
                Cycles += OpTiming.INC_WORD_REG;
                break;

            case 0x0b:
                Registers.BC--;
                Cycles += OpTiming.INC_WORD_REG;
                break;

            case 0x1b:
                Registers.DE--;
                Cycles += OpTiming.INC_WORD_REG;
                break;

            case 0x2b:
                Registers.HL--;
                Cycles += OpTiming.INC_WORD_REG;
                break;

            case 0x3b:
                Registers.SP--;
                Cycles += OpTiming.INC_WORD_REG;
                break;

            case 0xe0:
                //LDH (a8), A which is LD (0xff00+a8), a
                WriteByte(0xff00 + NextByte(), Registers.A);
                Cycles += OpTiming.LDH;
                break;

            case 0xf0:
                Registers.A = ReadByte(0xff00 + NextByte());
                Cycles     += OpTiming.LDH;
                break;

            //case var o when (o & 0xa8) == 0xa8:
            //    ControlUnit.XOR(Registers.GetRegById(o & 0x7));
            //    break;
            case 0x0e:
            case 0x1e:
            case 0x2e:
            case 0x3e:
                Registers.SetRegById(op >> 3, NextByte());
                Cycles += OpTiming.STORE_BYTE;
                break;

            case 0xe2:
                WriteByte(0xff00 + Registers.C, Registers.A);
                Cycles += OpTiming.STORE_BYTE;
                break;

            case 0xf2:
                Registers.A = ReadByte(0xff00 + Registers.C);
                Cycles     += OpTiming.STORE_BYTE;
                break;

            case 0x0c:
            case 0x1c:
            case 0x2c:
            case 0x3c:
                ControlUnit.IncReg(op >> 3);
                Cycles += OpTiming.ARITHMETIC;
                break;

            case 0x0d:
            case 0x2d:
            case 0x3d:
            case 0x1d:
                ControlUnit.DecReg(op >> 3);
                Cycles += OpTiming.ARITHMETIC;
                break;

            case 0x70:
            case 0x71:
            case 0x72:
            case 0x73:
            case 0x74:
            case 0x75:
            case 0x77:
                WriteByte(Registers.HL, Registers.GetRegById(0xf & op));
                Cycles += OpTiming.STORE_BYTE;
                break;

            case 0xcd:
                ControlUnit.Call(NextWord());
                Cycles += OpTiming.CALL;
                break;

            case 0xc9:
                ControlUnit.RET();
                Cycles += OpTiming.RET;
                break;

            case 0x48:
            case 0x49:
            case 0x4a:
            case 0x4b:
            case 0x4c:
            case 0x4d:
            case 0x4f:
                Registers.C = Registers.GetRegById(0x7 & op);
                Cycles     += OpTiming.LD;
                break;

            case 0x4e:
                Registers.C = Registers.GetRegById(0x7 & op);
                Cycles     += OpTiming.STORE_BYTE;
                break;

            case var o when(o >= 0x58 && o <= 0x5d) || o == 0x5f:
                Registers.E = Registers.GetRegById(0x7 & op);

                Cycles += OpTiming.LD;
                break;

            case 0x5e:
                Registers.E = Registers.GetRegById(0x7 & op);
                Cycles     += OpTiming.STORE_BYTE;
                break;

            case var o when(o >= 0x68 && o <= 0x6d) || o == 0x6f:
                Registers.L = Registers.GetRegById(0x7 & op);

                Cycles += OpTiming.LD;
                break;

            case 0x6e:
                Registers.L = Registers.GetRegById(0x7 & op);
                Cycles     += OpTiming.STORE_BYTE;
                break;

            case var o when(o >= 0x78 && o <= 0x7d) || o == 0x7f:
                Registers.A = Registers.GetRegById(0x7 & op);

                Cycles += OpTiming.LD;
                break;

            case 0x7e:
                Registers.A = Registers.GetRegById(0x7 & op);
                Cycles     += OpTiming.STORE_BYTE;
                break;

            case 0x06:
            case 0x16:
            case 0x26:
                Registers.SetRegById((op >> 4) << 1, NextByte());
                Cycles += OpTiming.STORE_BYTE;
                break;

            case 0x36:
                Registers.SetRegById((op >> 4) << 1, NextByte());
                Cycles += OpTiming.LD_WORD;
                break;

            case 0xc1:
            case 0xd1:
            case 0xe1:
            case 0xf1:
                Registers.LoadWordRegisterPair2((op >> 4) & 3, ControlUnit.POP());
                Cycles += OpTiming.POP;
                break;

            case 0xc5:
            case 0xd5:
            case 0xe5:
            case 0xf5:
                ControlUnit.Push(Registers.ReadWordRegisterPair2((op >> 4) & 3));
                Cycles += OpTiming.PUSH;
                break;

            case 0x05:
            case 0x15:
            case 0x25:
            case 0x35:
                ControlUnit.DecReg((op >> 4) << 1);
                break;

            case 0x04:
            case 0x14:
            case 0x24:
                ControlUnit.IncReg((op >> 4) << 1);
                Cycles += OpTiming.ARITHMETIC;
                break;

            case 0x34:
                ControlUnit.IncReg((op >> 4) << 1);
                Cycles += OpTiming.ARITHMETIC_LOAD;
                break;

            case 0xfe:
                ControlUnit.CP(NextByte());
                Cycles += OpTiming.ARITHMETIC_LOAD;
                break;

            case var o when o >= 0xb8 && o <= 0xbf && o != 0xbe:
                ControlUnit.CP(Registers.GetRegById(o & 0x7));
                Cycles += OpTiming.ARITHMETIC;
                break;

            case 0xbe:
                ControlUnit.CP(Registers.GetRegById(op & 0x7));
                Cycles += OpTiming.ARITHMETIC_LOAD;
                break;

            case var o when o >= 0xa8 && o <= 0xaf && o != 0xae:
                ControlUnit.XOR(Registers.GetRegById(o & 0x7));
                Cycles += OpTiming.ARITHMETIC;
                break;

            case 0xae:
                ControlUnit.XOR(Registers.GetRegById(op & 0x7));
                Cycles += OpTiming.ARITHMETIC_LOAD;
                break;

            case 0xea:
                WriteByte(NextWord(), Registers.A);
                Cycles += OpTiming.LDH;
                break;

            case 0xfa:
                Registers.A = mmu.rb(NextWord());
                Cycles     += OpTiming.LDH;
                Cycles     += OpTiming.ARITHMETIC;
                break;

            case 0x76:
                Cycles += OpTiming.ARITHMETIC;
                Halt1   = true;
                if (!IME && (mmu.IE & mmu.IF) > 0)
                {
                    Halt1 = false;
                }
                break;

            case 0xfb:
                //Set Interrupt master enable.
                pendingIME = 2;
                Cycles    += OpTiming.EI;
                break;

            case 0xf3:
                //Disable interrupt;
                IME     = false;
                Cycles += OpTiming.EI;
                break;

            case 0xf6:
                ControlUnit.ORA(NextByte());
                Cycles += OpTiming.ARITHMETIC_LOAD;
                break;

            case 0xd9:
                //RETI
                pendingIME = 1;
                ControlUnit.RET();
                Cycles += OpTiming.RET;
                break;

            case var o when o >= 0xb0 && o <= 0xb7 && o != 0xb6:
                ControlUnit.ORA(Registers.GetRegById(o & 0x7));
                Cycles += OpTiming.ARITHMETIC;
                break;

            case 0xb6:
                ControlUnit.ORA(Registers.GetRegById(op & 0x7));
                Cycles += OpTiming.ARITHMETIC_LOAD;
                break;

            //suba
            case var o when o >= 0x90 && o <= 0x97 && o != 0x96:
                ControlUnit.SUBA(0x7 & o);
                Cycles += OpTiming.ARITHMETIC;
                break;

            case 0x96:
                ControlUnit.SUBA(0x7 & op);
                Cycles += OpTiming.ARITHMETIC_LOAD;
                break;

            case var o when o >= 0x98 && o <= 0x9f && o != 0x9e:
                ControlUnit.SUBC(0x7 & o);
                Cycles += OpTiming.ARITHMETIC;
                break;

            case 0x9e:
                ControlUnit.SUBC(0x7 & op);
                Cycles += OpTiming.ARITHMETIC_LOAD;
                break;

            case var o when o >= 0x40 && o <= 0x7f && (o & 0x7) != 0x6 && (o & 0xf0) != 0x70:
                //Catch all cases where load takes 4 cycles.
                LoadByte(o);
                Cycles += OpTiming.LD;
                break;

            case var o when o >= 0x40 && o <= 0x7f:
                //catch the rest of the cases which it takes 8.
                LoadByte(o);
                Cycles += OpTiming.STORE_BYTE;
                break;

            case var o when o >= 0x80 && o <= 0x87 && o != 0x86:
                ControlUnit.ADDA(Registers.GetRegById(o & 0x7));
                Cycles += OpTiming.ARITHMETIC;
                break;

            case 0x86:
                ControlUnit.ADDA(Registers.GetRegById(op & 0x7));
                Cycles += OpTiming.ARITHMETIC_LOAD;
                break;

            case 0xc6:
                ControlUnit.ADDA(NextByte());
                Cycles += OpTiming.ARITHMETIC_LOAD;
                break;

            case 0xc3:
                ControlUnit.JP(NextWord());
                Cycles += OpTiming.JP;
                break;



            case var o when(o >= 0xa0 && o <= 0xa5) || o == 0xa7:
                ControlUnit.AND(Registers.GetRegById(o & 7));

                Cycles += OpTiming.ARITHMETIC;
                break;

            case 0xa6:
                Cycles += OpTiming.ARITHMETIC_LOAD;
                ControlUnit.AND(Registers.GetRegById(op & 7));
                break;

            case 0x2f:
                ControlUnit.CPL();
                break;

            case 0xe6:
                ControlUnit.AND(NextByte());
                Cycles += OpTiming.ARITHMETIC_LOAD;
                break;

            case 0xcf:
                ControlUnit.RST(0x8);
                break;

            case 0xdf:
                ControlUnit.RST(0x18);
                break;

            case 0xef:
                ControlUnit.RST(0x28);
                break;

            case 0xff:
                ControlUnit.RST(0x38);
                break;

            case 0xc7:
                ControlUnit.RST(0);
                break;

            case 0xd7:
                ControlUnit.RST(0x10);
                break;

            case 0xe7:
                ControlUnit.RST(0x20);
                break;

            case 0xf7:
                ControlUnit.RST(0x30);
                break;

            case 0xe9:
                ControlUnit.JP(Registers.HL);
                Cycles += OpTiming.ARITHMETIC;
                break;

            case 0x37:
                Registers.Carry     = true;
                Registers.Negative  = false;
                Registers.HalfCarry = false;
                Cycles += OpTiming.ARITHMETIC;
                break;

            case 0x3f:
                Registers.Carry     = !Registers.Carry;
                Registers.Negative  = false;
                Registers.HalfCarry = false;
                Cycles += OpTiming.ARITHMETIC;
                break;

            case 0xd8:
            case 0xc8:
            case 0xc0:
            case 0xd0:
                ControlUnit.RETC(op);
                break;

            case 0xc4:
            case 0xd4:
            case 0xcc:
            case 0xdc:
                ControlUnit.CALLCC(op, NextWord());
                break;

            case 0x1f:
                ControlUnit.RRA();
                break;

            case 0xee:
                ControlUnit.XOR(NextByte());
                Cycles += OpTiming.ARITHMETIC_LOAD;
                break;

            case 0xd6:
                ControlUnit.SUB(NextByte());
                break;

            case 0xce:
                ControlUnit.ADDC(NextByte());
                Cycles += OpTiming.ARITHMETIC_LOAD;
                break;

            case 0xde:
                ControlUnit.SUBCv(NextByte());
                break;

            case var o when(o >= 0x88 && o <= 0x8d) || o == 0x8f:
                ControlUnit.ADDC(Registers.GetRegById(o & 0x7));

                Cycles += OpTiming.ARITHMETIC;
                break;

            case 0x8e:
                ControlUnit.ADDC(Registers.GetRegById(op & 0x7));
                Cycles += OpTiming.ARITHMETIC_LOAD;
                break;

            case 0x27:
                ControlUnit.DAA();
                break;

            case 0xf8:
                ControlUnit.LDSPe8((sbyte)NextByte());
                break;

            case 0xca:
            case 0xda:
            case 0xd2:
            case 0xc2:
                ControlUnit.JPCC(op, NextWord());
                break;

            case 0xf9:
                Registers.SP = Registers.HL;
                Cycles       = OpTiming.ARITHMETIC_LOAD;
                break;

            case 0xe8:
                ControlUnit.ADDSP((sbyte)NextByte());
                break;

            case 0x0f:
                Registers.A    = ControlUnit.RRC(Registers.A);
                Registers.Zero = false;
                Cycles        += OpTiming.SHIFT;
                break;

            default:
                throw new NotImplementedException($"The op code {op:X2} has not been implemented yet.");
            }
        }