The Most Common Flags
This is a list of the most common CPU status register flags, implemented in almost all modern processors.
| Flag | Name | Description |
|---|---|---|
| Z | Zero flag | Indicates that the result of an arithmetic or logical operation (or, sometimes, a load) was zero. |
| C | Carry flag | Enables numbers larger than a single word to be added/subtracted by carrying a binary digit from a less significant word to the least significant bit of a more significant word as needed. It is also used to extend bit shifts and rotates in a similar manner on many processors (sometimes done via a dedicated X flag). |
| S / N | Sign flag / Negative flag | Indicates that the result of a mathematical operation is negative. In some processors, the N and S flags are distinct with different meanings and usage: One indicates whether the last result was negative whereas the other indicates whether a subtraction or addition has taken place. |
| V / O / W | Overflow flag | Indicates that the signed result of an operation is too large to fit in the register width using twos complement representation. |
| P | Parity flag | Indicates whether the number of set bits of the last result is odd or even. |
Read more about this topic: Status Register
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