ch2-flags

# ch2-flags - 8086 flags condition and control EE 3750...

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8086 flags: condition and control EE 3750 2 Condition flags CF (carry flag) — addition sets flag if carry out of MSB generate; subtraction sets flag if borrow needed. PF (parity flag) — set to 1 if low-order 8 bits (low order byte) contain even number of 1’s (that is, gives odd parity) AF (auxiliary carry flag) — set if carry out of bit 3 during addition or borrow by bit 3 during subtraction. Used exclusively for BCD arithmetic. ZF (zero flag) — set to 1 if result is 0; to 0 if result is nonzero SF (sign flag) — equal to MSB of result OF (overflow flag) — set if overflow occurs (that is, if carry in to MSB is not equal to carry out from MSB)

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3 Example CF (carry flag) — carry out of MSB PF (parity flag) — set to 1 if low- order 8 bits (low order byte) contain even number of 1’s AF (auxiliary carry flag) —carry out of bit 3 ZF (zero flag) — set to 1 if result is 0; to 0 if result is nonzero SF (sign flag) —MSB of result
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## This note was uploaded on 01/25/2012 for the course EE 3750 taught by Professor Desouza during the Fall '08 term at LSU.

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ch2-flags - 8086 flags condition and control EE 3750...

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