上QQ阅读APP看书，第一时间看更新
Bit #2 - parity flag
The parity flag (PF) is set to 1 in case the number of 1s in the least significant byte is even; otherwise, the flag is set to zero.
The parity flag (PF) is set to 1 in case the number of 1s in the least significant byte is even; otherwise, the flag is set to zero.