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Remove duplicated code between addressing modes in ADC. Closes #4.

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This commit is contained in:
Mike Naberezny 2009-08-07 13:13:40 -07:00
parent e4f101b878
commit ccf950019f
1 changed files with 6 additions and 34 deletions
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40
src/py65/devices/mpu6502.py
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@ -248,7 +248,11 @@ class MPU:
self.FlagsNZ(self.a) self.FlagsNZ(self.a)
def opADC(self, x): def opADC(self, x):
data=self.ByteAt(x()) if callable(x):
data = self.ByteAt(x())
else:
data = x
if self.flags & self.DECIMAL: if self.flags & self.DECIMAL:
if self.flags & self.CARRY: if self.flags & self.CARRY:
tmp = 1 tmp = 1
@ -737,39 +741,7 @@ class MPU:
@instruction(name="ADC", mode="imm", cycles=2) @instruction(name="ADC", mode="imm", cycles=2)
def inst_0x69(self): def inst_0x69(self):
data = self.ImmediateByte() self.opADC(self.ImmediateByte())
if self.flags & self.CARRY:
tmp = 1
else:
tmp = 0
if self.flags & self.DECIMAL:
data = convert_to_bin(data) + convert_to_bin(self.a) + tmp
self.flags &= ~(self.CARRY+self.OVERFLOW+self.NEGATIVE+self.ZERO)
if data > 99:
self.flags |= self.CARRY+self.OVERFLOW
data -= 100
if data == 0:
self.flags |= self.ZERO
else:
self.flags |= self.data & 128
self.a = convert_to_bcd(data)
else:
if self.flags & self.CARRY:
tmp = 1
else:
tmp = 0
data += self.a + tmp
self.flags &= ~(self.CARRY+self.OVERFLOW+self.NEGATIVE+self.ZERO)
if data > 255:
self.flags |= self.OVERFLOW + self.CARRY
data &= 255
if data == 0:
self.flags |= self.ZERO
else:
self.flags |= data & 128
self.a=data
self.pc += 1 self.pc += 1
@instruction(name="ROR", mode="acc", cycles=2) @instruction(name="ROR", mode="acc", cycles=2)