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Add 6522 support for stz abs16 and stz abs16,x

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tomcw 2021-02-05 22:30:05 +00:00
parent fcafa18340
commit f302e88f55
1 changed files with 13 additions and 1 deletions
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14
source/Mockingboard.cpp
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@ -383,6 +383,18 @@ static UINT GetOpcodeCycles(BYTE reg)
opcodeCycles = 5;
opcode = opcodeMinus2;
}
else if (opcodeMinus3 == 0x9C && GetMainCpu() == CPU_65C02) // stz abs16 : 65C02-only
{
opcodeCycles = 4;
opcode = opcodeMinus3;
abs16 = true;
}
else if (opcodeMinus3 == 0x9E && GetMainCpu() == CPU_65C02) // stz abs16,x : 65C02-only
{
opcodeCycles = 5;
opcode = opcodeMinus3;
abs16 = true;
}
else
{
_ASSERT(0);
@ -405,7 +417,7 @@ static UINT GetOpcodeCycles(BYTE reg)
{
addr16 = mem[(regs.pc-2)&0xffff] | (mem[(regs.pc-1)&0xffff]<<8);
if (opcode == 0x99) addr16 += regs.y;
if (opcode == 0x9D) addr16 += regs.x;
if (opcode == 0x9D || opcode == 0x9E) addr16 += regs.x;
}
// Check we've reverse looked-up the 6502 opcode correctly