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Get the MC6809 processor compiling. Still untested.

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Signed-off-by: Adrian Conlon <adrian.conlon@gmail.com>
This commit is contained in:
Adrian Conlon 2019-04-10 23:15:26 +01:00
parent 6b33d2b5a5
commit 294c71c228
1 changed files with 53 additions and 48 deletions
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101
MC6809/MC6809.cs
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@ -1339,7 +1339,6 @@
var specifier2 = Chip.LowNibble(data); var specifier2 = Chip.LowNibble(data);
var type8 = (specifier1 & (int)Bits.Bit3) == 0; // 8 bit exchange? var type8 = (specifier1 & (int)Bits.Bit3) == 0; // 8 bit exchange?
if (type8) if (type8)
{ {
ref var register1 = ref this.ReferenceTransfer8(specifier1); ref var register1 = ref this.ReferenceTransfer8(specifier1);
@ -1356,11 +1355,11 @@
private byte INC(byte operand) private byte INC(byte operand)
{ {
const register16_t addition = operand + 1; var addition = new Register16(operand + 1);
const auto result = addition.low; var result = addition.Low;
adjustNZ(result); this.AdjustNZ(result);
adjustOverflow(operand, 1, addition); this.AdjustOverflow(operand, 1, addition);
adjustHalfCarry(operand, 1, result); this.AdjustHalfCarry(operand, 1, result);
return result; return result;
} }
@ -1370,26 +1369,26 @@
private byte LSR(byte operand) private byte LSR(byte operand)
{ {
setFlag(CC(), CF, operand & Bit0); SetFlag(this.CC, StatusBits.CF, operand & (byte)Bits.Bit0);
adjustNZ(operand >>= 1); this.AdjustNZ(operand >>= 1);
return operand; return operand;
} }
private Register16 MUL(byte first, byte second) private Register16 MUL(byte first, byte second)
{ {
const register16_t result = first * second; var result = new Register16(first * second);
adjustZero(result); this.AdjustZero(result);
setFlag(CC(), CF, result.low & Bit7); SetFlag(this.CC, StatusBits.CF, result.Low & (byte)Bits.Bit7);
return result; return result;
} }
private byte NEG(byte operand) private byte NEG(byte operand)
{ {
setFlag(CC(), VF, operand == Bit7); SetFlag(this.CC, StatusBits.VF, operand == (byte)Bits.Bit7);
const register16_t result = 0 - operand; var result = new Register16(0 - operand);
operand = result.low; operand = result.Low;
adjustNZ(operand); this.AdjustNZ(operand);
adjustCarry(result); this.AdjustCarry(result);
return operand; return operand;
} }
@ -1501,20 +1500,20 @@
private byte ROL(byte operand) private byte ROL(byte operand)
{ {
const auto carryIn = carry(); var carryIn = this.Carry;
setFlag(CC(), CF, operand & Bit7); SetFlag(this.CC, StatusBits.CF, operand & (byte)Bits.Bit7);
setFlag(CC(), VF, ((operand & Bit7) >> 7) ^ ((operand & Bit6) >> 6)); SetFlag(this.CC, StatusBits.VF, ((operand & (byte)Bits.Bit7) >> 7) ^ ((operand & (byte)Bits.Bit6) >> 6));
const uint8_t result = (operand << 1) | carryIn; var result = (byte)((operand << 1) | carryIn);
adjustNZ(result); this.AdjustNZ(result);
return result; return result;
} }
private byte ROR(byte operand) private byte ROR(byte operand)
{ {
const auto carryIn = carry(); var carryIn = this.Carry;
setFlag(CC(), CF, operand & Bit0); SetFlag(this.CC, StatusBits.CF, operand & (byte)Bits.Bit0);
const uint8_t result = (operand >> 1) | (carryIn << 7); var result = (byte)((operand >> 1) | (carryIn << 7));
adjustNZ(result); this.AdjustNZ(result);
return result; return result;
} }
@ -1526,56 +1525,62 @@
private byte SUB(byte operand, byte data, byte carry = 0) private byte SUB(byte operand, byte data, byte carry = 0)
{ {
const register16_t subtraction = operand - data - carry; var subtraction = new Register16(operand - data - carry);
adjustSubtraction(operand, data, subtraction); this.AdjustSubtraction(operand, data, subtraction);
return subtraction.low; return subtraction.Low;
} }
private Register16 SUB(Register16 operand, Register16 data) private Register16 SUB(Register16 operand, Register16 data)
{ {
const uint32_t subtraction = operand.word - data.word; var subtraction = (uint)(operand.Word - data.Word);
adjustSubtraction(operand, data, subtraction); this.AdjustSubtraction(operand, data, subtraction);
return subtraction & Mask16; return new Register16(subtraction & (uint)Mask.Mask16);
} }
private byte SEX(byte from) private byte SEX(byte from)
{ {
adjustNZ(from); this.AdjustNZ(from);
return from & Bit7 ? Mask8 : 0; return (from & (byte)Bits.Bit7) != 0 ? (byte)Mask.Mask8 : (byte)0;
} }
private void SWI() private void SWI()
{ {
saveEntireRegisterState(); this.SaveEntireRegisterState();
setFlag(CC(), IF); // Disable IRQ SetFlag(this.CC, StatusBits.IF); // Disable IRQ
setFlag(CC(), FF); // Disable FIRQ SetFlag(this.CC, StatusBits.FF); // Disable FIRQ
jump(getWordPaged(0xff, SWIvector)); this.Jump(this.GetWordPaged(0xff, SWIvector));
} }
private void SWI2() private void SWI2()
{ {
saveEntireRegisterState(); this.SaveEntireRegisterState();
jump(getWordPaged(0xff, SWI2vector)); this.Jump(this.GetWordPaged(0xff, SWI2vector));
} }
private void SWI3() private void SWI3()
{ {
saveEntireRegisterState(); this.SaveEntireRegisterState();
jump(getWordPaged(0xff, SWI3vector)); this.Jump(this.GetWordPaged(0xff, SWI3vector));
} }
private void TFR(byte data) private void TFR(byte data)
{ {
const auto reg1 = highNibble(data); var specifier1 = Chip.HighNibble(data);
const auto reg2 = lowNibble(data); var specifier2 = Chip.LowNibble(data);
const bool type8 = !!(reg1 & Bit3); // 8 bit transfer?
ASSUME(type8 == !!(reg2 & Bit3)); // Regardless, the register transfer must be equivalent
var type8 = (specifier1 & (int)Bits.Bit3) == 0; // 8 bit transfer?
if (type8) if (type8)
referenceTransfer8(reg2) = referenceTransfer8(reg1); {
ref var register1 = ref this.ReferenceTransfer8(specifier1);
ref var register2 = ref this.ReferenceTransfer8(specifier2);
register2 = register1;
}
else else
referenceTransfer16(reg2) = referenceTransfer16(reg1); {
var register1 = this.ReferenceTransfer16(specifier1);
var register2 = this.ReferenceTransfer16(specifier2);
register2 = register1;
}
} }
private void TST(byte data) => this.CMP(data, 0); private void TST(byte data) => this.CMP(data, 0);