HASH: CRC-16

[Thaddy]

Marco, I can add it, but are you sure that is OK? It only uses 15 bits.. that's wrong.. (Basically all other CRC16's are actually 17 bits, yup, within a word , through the shift-out shift-in ) But if it is a common one and you can test it, I will include it.
See https://en.wikipedia.org/wiki/Cyclic_redundancy_check

Sure it is not a CRC15? Can you identify it for me in that wiki table? Appreciated.

[marcov]

No, leave it out. It was a long time ago.

As it happens that customer recently got live again, so maybe I'll pick it up in the near future.

[Thaddy]

Posts crossed: can you identify it? I am curious and will test $BEEF
'123456789'

[Thaddy]

I delved in my sources, and it seems that microchip uses a different algo, I added a CCIT implementation in the same vein for reference.

I have the references for your implementation now and will include it.
It is called a CLASSB_CRC16 (without reflection) a.k.a. RF69 as used in e.g. radio communications and sensors. See ATMEL, Microchip, ISO/IEC CD 14443-3.3  appendix B.
It is NOT CCITT compliant, although it uses the same start value of zero, $1021 it uses a different polynomial using only 15 bit, but a very common implementation in hardware, so it should be in.