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Tidy up the 10 addressing mode write set to make it clearer when memory writes occur.

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Signed-off-by: Adrian.Conlon <adrian.conlon@gmail.com>
This commit is contained in:
Adrian.Conlon 2017-08-07 21:25:21 +01:00
parent aa720c4c12
commit 99c2e2a719
1 changed files with 13 additions and 21 deletions
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34
M6502/inc/mos6502.h
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@ -175,7 +175,7 @@ namespace EightBit {
m_memory.ADDRESS() = MEMPTR();
if (m_memory.ADDRESS().low == Mask8)
++cycles;
return m_memory.read();
return getByte();
}
uint8_t AM_AbsoluteY() {
@ -183,7 +183,7 @@ namespace EightBit {
m_memory.ADDRESS() = MEMPTR();
if (m_memory.ADDRESS().low == Mask8)
++cycles;
return m_memory.read();
return getByte();
}
uint8_t AM_ZeroPageX() {
@ -206,7 +206,7 @@ namespace EightBit {
m_memory.ADDRESS() = MEMPTR();
if (m_memory.ADDRESS().low == Mask8)
++cycles;
return m_memory.read();
return getByte();
}
#pragma endregion Addressing modes, read
@ -385,26 +385,18 @@ namespace EightBit {
return 0xff;
}
void AM_10(int bbb, uint8_t value, bool fetched = false) {
void AM_10(int bbb, uint8_t value) {
switch (bbb) {
case 0b000:
assert(false);
break;
case 0b001:
fetched ? m_memory.write(MEMPTR(), value) : AM_ZeroPage(value);
break;
case 0b010:
AM_A(value);
break;
case 0b001:
case 0b011:
fetched ? m_memory.write(MEMPTR(), value) : AM_Absolute(value);
break;
case 0b101:
fetched ? m_memory.write(MEMPTR(), value) : AM_ZeroPageX(value);
break;
case 0b111:
fetched ? m_memory.write(MEMPTR(), value) : AM_AbsoluteX(value);
m_memory.write(MEMPTR(), value);
break;
case 0b000:
case 0b100:
case 0b110:
throw std::domain_error("Illegal addressing mode");
@ -470,37 +462,37 @@ namespace EightBit {
void ASL(int bbb) {
auto operand = AM_10(bbb);
ASL(operand);
AM_10(bbb, operand, true);
AM_10(bbb, operand);
}
void ROL(int bbb) {
auto operand = AM_10(bbb);
ROL(operand);
AM_10(bbb, operand, true);
AM_10(bbb, operand);
}
void LSR(int bbb) {
auto operand = AM_10(bbb);
LSR(operand);
AM_10(bbb, operand, true);
AM_10(bbb, operand);
}
void ROR(int bbb) {
auto operand = AM_10(bbb);
ROR(operand);
AM_10(bbb, operand, true);
AM_10(bbb, operand);
}
void DEC(int bbb) {
auto operand = AM_10(bbb);
adjustNZ(--operand);
AM_10(bbb, operand, true);
AM_10(bbb, operand);
}
void INC(int bbb) {
auto operand = AM_10(bbb);
adjustNZ(++operand);
AM_10(bbb, operand, true);
AM_10(bbb, operand);
}
void ROR(uint8_t& output);