1, parity
To verify the original binary data of odd and even number 1:
- Odd parity, an even number of the original 1, followed by one of an odd number of 1 composition. Original has an odd number 1, followed by an odd number of add 1 or 0;
- Even parity, an even number of the original 1, followed by one of an even number of 0's. Original has an odd number 1, followed by an even number or add a 1;
Essentially, it is to allow the output of a fixed odd or even number of 1s.
2, the accumulation and verification
The number of the original data 1 is performed counting statistics, the statistical results directly behind the loading raw data verification.
In order to standardize Later, this count the number of modulo 255, locked between the range of 0 to 255.
3, CRC redundancy check
I will not start to explain this, the following links will this checksum said very clearly. Here you will initiate direct external redirect response
There is a very interesting explanation: https://blog.csdn.net/BeautifulPebbles/article/details/86751411
Before they get to know the CRC, and forgotten over time, the brother read this blog, get plainly, very easy to understand!