– shows the status of the microprocessor before/after an operation
– S (sign flag), Z (zero flag), AC (auxillary carry flag), P (parity flag) & CY (carry flag)
 |
| Flag Register In Microprocessor |
Sign Flag:
• Used for indicating the sign of the data in the accumulator
• The sign flag is set if negative (1 – negative)
• The sign flag is reset if positive (0 –positive)
Zero Flag:
– Is set if result obtained after an operation is 0
– Is set following an increment or decrement operation of that register
 |
| Zero Flag |
Carry Flag:
– Is set if there is a carry or borrow from arithmetic operation
 |
| Carry Flag: |
Auxiliary Carry Flag: – Is set if there is a carry out of bit 3
Parity Flag:
– Is set if parity is even
– Is cleared if parity is odd
