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Merge branch 'master' of https://github.com/MoleskiCoder/EightBit

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This commit is contained in:
Adrian.Conlon 2017-08-29 17:28:24 +01:00
commit 9da58a5af7
2 changed files with 23 additions and 16 deletions
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31
LR35902/src/LR35902.cpp
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@ -13,7 +13,7 @@ EightBit::LR35902::LR35902(Bus& memory)
void EightBit::LR35902::reset() { void EightBit::LR35902::reset() {
IntelProcessor::reset(); IntelProcessor::reset();
SP().word = 0xfffe; SP().word = Mask16 - 1;
di(); di();
} }
@ -21,11 +21,10 @@ void EightBit::LR35902::initialise() {
IntelProcessor::initialise(); IntelProcessor::initialise();
AF().word = 0xffff; AF().word = Mask16;
BC().word = Mask16;
BC().word = 0xffff; DE().word = Mask16;
DE().word = 0xffff; HL().word = Mask16;
HL().word = 0xffff;
m_prefixCB = false; m_prefixCB = false;
} }
@ -687,13 +686,13 @@ void EightBit::LR35902::executeOther(int x, int y, int z, int p, int q) {
break; break;
case 5: { // GB: ADD SP,dd case 5: { // GB: ADD SP,dd
auto before = SP().word; auto before = SP().word;
auto value = fetchByte(); int8_t value = fetchByte();
auto result = before + (int8_t)value; auto result = before + value;
SP().word = result; SP().word = result;
auto carried = before ^ value ^ result; auto carried = before ^ value ^ (result & Mask16);
clearFlag(f, ZF | NF); clearFlag(f, ZF | NF);
setFlag(f, CF, carried & 0x100); setFlag(f, CF, carried & Bit8);
setFlag(f, HC, carried & 0x10); setFlag(f, HC, carried & Bit4);
} }
cycles += 4; cycles += 4;
break; break;
@ -703,13 +702,13 @@ void EightBit::LR35902::executeOther(int x, int y, int z, int p, int q) {
break; break;
case 7: { // GB: LD HL,SP + dd case 7: { // GB: LD HL,SP + dd
auto before = SP().word; auto before = SP().word;
auto value = fetchByte(); int8_t value = fetchByte();
auto result = before + (int8_t)value; auto result = before + value;
HL().word = result; HL().word = result;
auto carried = before ^ value ^ result; auto carried = before ^ value ^ (result & Mask16);
clearFlag(f, ZF | NF); clearFlag(f, ZF | NF);
setFlag(f, CF, carried & 0x100); setFlag(f, CF, carried & Bit8);
setFlag(f, HC, carried & 0x10); setFlag(f, HC, carried & Bit4);
} }
cycles += 3; cycles += 3;
break; break;

8
inc/Processor.h
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@ -36,6 +36,14 @@ namespace EightBit {
Mask6 = Bit6 - 1, Mask6 = Bit6 - 1,
Mask7 = Bit7 - 1, Mask7 = Bit7 - 1,
Mask8 = Bit8 - 1, Mask8 = Bit8 - 1,
Mask9 = Bit9 - 1,
Mask10 = Bit10 - 1,
Mask11 = Bit11 - 1,
Mask12 = Bit12 - 1,
Mask13 = Bit13 - 1,
Mask14 = Bit14 - 1,
Mask15 = Bit15 - 1,
Mask16 = Bit16 - 1,
}; };
static int highNibble(int value) { return value >> 4; } static int highNibble(int value) { return value >> 4; }