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Correct a few small LR35902 issues.

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Signed-off-by: Adrian.Conlon <adrian.conlon@gmail.com>
This commit is contained in:
Adrian.Conlon 2017-06-11 22:07:48 +01:00
parent 0291970427
commit eb8a93726d
1 changed files with 7 additions and 11 deletions
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18
LR35902/src/LR35902.cpp
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@ -108,13 +108,10 @@ bool EightBit::LR35902::returnConditionalFlag(int flag) {
return returnConditional(!(F() & ZF));
case 1: // Z
return returnConditional(F() & ZF);
break;
case 2: // NC
return returnConditional(!(F() & CF));
break;
case 3: // C
return returnConditional(F() & CF);
break;
}
throw std::logic_error("Unhandled RET conditional");
}
@ -512,7 +509,7 @@ void EightBit::LR35902::executeOther(int x, int y, int z, int p, int q) {
break;
default: { // JR cc,d
auto condition = y - 4;
if (y < 4) {
if (condition < 4) {
if (jrConditionalFlag(condition))
cycles++;
cycles += 2;
@ -524,8 +521,7 @@ void EightBit::LR35902::executeOther(int x, int y, int z, int p, int q) {
case 1: // 16-bit load immediate/add
switch (q) {
case 0: // LD rp,nn
fetchWord();
RP(p) = MEMPTR();
Processor::fetchWord(RP(p));
cycles += 3;
break;
case 1: // ADD HL,rp
@ -778,7 +774,7 @@ void EightBit::LR35902::executeOther(int x, int y, int z, int p, int q) {
switch (y) {
case 0: // JP nn
fetchWord();
pc = MEMPTR();
jump();
cycles += 4;
break;
case 1: // CB prefix
@ -796,8 +792,8 @@ void EightBit::LR35902::executeOther(int x, int y, int z, int p, int q) {
}
break;
case 4: // Conditional call: CALL cc[y], nn
fetchWord();
callConditionalFlag(y);
if (callConditionalFlag(y))
cycles += 3;
cycles += 3;
break;
case 5: // PUSH & various ops
@ -810,8 +806,8 @@ void EightBit::LR35902::executeOther(int x, int y, int z, int p, int q) {
switch (p) {
case 0: // CALL nn
fetchWord();
callConditional(true);
cycles += 3;
call();
cycles += 6;
break;
}
}