How to calculate a CRC16 checksum Stack Overflow?
How to calculate a CRC16 checksum Stack Overflow?
Following is the code generated by crcany for that CRC definition. This code assumes a little-endian architecture for the word-wise calculation, e.g. Intel x86 and x86-64, and it assumes that uintmax_t is 64 bits. crcany can be used to generate alternative code for big-endian and other word sizes.
How is the CRC algorithm implemented in C + +?
The CRC algorithm should then be iterated over all of the data bytes, as well as the bits within those bytes. The result of making these two changes is the code shown in Listing 2. This implementation of the CRC calculation is still just as inefficient as the previous one.
How to calculate the CRC of a byte?
// The _bit, _byte, and _word routines return the CRC of the len bytes at mem, // applied to the previous CRC value, crc. If mem is NULL, then the other // arguments are ignored, and the initial CRC, i.e. the CRC of zero bytes, is // returned. Those routines will all return the same result, differing only in // speed and code complexity.
Which is a good CRC for 16 bit?
One of the good 16-bit performers in Koopman’s tables that is also in the catalog of CRCs used in practice is CRC-16/DNP. It has very good performance detecting up to 6-bit errors in a packet. Following is the code generated by crcany for that CRC definition.
What’s the fastest way to update the CRC?
The routine can be called successively with chunks of the data to update the CRC. You can unroll the inner loop for speed, though your compiler might do that for you anyway. Obviously the biggest lookup table will bring the best performance, but you can use any (smaller) table for 16,8 or 4bit lookups.
Is there a fast and Slim CRC algorithm?
CRC32 algorithm is exactly what I’m looking for but I can’t use it because the table it requires is way too huge (it is for an embedded systems where ressources are VERY rare). So: any suggestions for a fast and slim CRC algorithm? It does not matter when collissions are a bit more probable than with the original CRC32.