private static bool imm(uint wInstr, Mos65816Disassembler dasm)
{
if (!dasm.rdr.TryReadByte(out byte imm))
{
return(false);
}
dasm.ops.Add(ImmediateOperand.Byte(imm));
return(true);
}
// abs = $0000
private static bool abs(uint wInstr, Mos65816Disassembler dasm)
{
if (!dasm.rdr.TryReadLeUInt16(out ushort imm))
{
return(false);
}
dasm.ops.Add(new Operand(PrimitiveType.Byte)
{
Mode = AddressMode.Absolute,
Offset = Constant.Word16(imm),
});
return(true);
}
// idp = ($00)
private static bool idp(uint wInstr, Mos65816Disassembler dasm)
{
if (!dasm.rdr.TryReadByte(out byte imm))
{
return(false);
}
dasm.ops.Add(new Operand(PrimitiveType.Byte)
{
Mode = AddressMode.DirectPageIndirect,
Offset = Constant.Byte(imm),
});
return(true);
}
private static bool sr(uint wInstr, Mos65816Disassembler dasm)
{
if (!dasm.rdr.TryReadByte(out byte imm))
{
return(false);
}
dasm.ops.Add(new Operand(PrimitiveType.Byte)
{
Mode = AddressMode.StackRelative,
Offset = Constant.Byte(imm),
Register = Registers.s,
});
return(true);
}
// rell = $0000 (16 bits PC-relative)
private static bool rell(uint wInstr, Mos65816Disassembler dasm)
{
if (!dasm.rdr.TryReadLeInt16(out short rel))
{
return(false);
}
dasm.ops.Add(new Operand(PrimitiveType.Byte)
{
Mode = AddressMode.Immediate,
Offset = Constant.Word16((ushort)((int)dasm.rdr.Address.Offset + rel)),
});
return(true);
}
// isy = ($00,S),Y
private static bool isy(uint wInstr, Mos65816Disassembler dasm)
{
if (!dasm.rdr.TryReadByte(out byte imm))
{
return(false);
}
dasm.ops.Add(new Operand(PrimitiveType.Byte)
{
Mode = AddressMode.StackRelativeIndirectIndexedY,
Offset = Constant.Byte(imm),
Register = Mos65816Architecture.Y
});
return(true);
}
// bm = $00,$00
private static bool bm(uint wInstr, Mos65816Disassembler dasm)
{
if (!dasm.rdr.TryReadByte(out byte bankDst) ||
!dasm.rdr.TryReadByte(out byte bankSrc))
{
return(false);
}
dasm.ops.Add(new Operand(PrimitiveType.Byte)
{
Mode = AddressMode.Immediate,
Offset = Constant.Byte(bankDst)
});
dasm.ops.Add(new Operand(PrimitiveType.Byte)
{
Mode = AddressMode.Immediate,
Offset = Constant.Byte(bankSrc)
});
return(true);
}
// alx = $000000,X
private static bool alx(uint wInstr, Mos65816Disassembler dasm)
{
if (!dasm.rdr.TryReadLeUInt16(out ushort immLo))
{
return(false);
}
if (!dasm.rdr.TryReadByte(out byte immHi))
{
return(false);
}
var abs = ((uint)immHi << 16) | immLo;
dasm.ops.Add(new Operand(PrimitiveType.Byte)
{
Mode = AddressMode.AbsoluteLongX,
Offset = Constant.Create(Mos65816Architecture.Word24, abs),
});
return(true);
}