(Thanks to Greys for the nice Graph)
SAMD21 Cortex M0+ @ 48MHz:
1KB
Maxim (iButton) FastCRC: Value:0x78, Time: 353 us (23.21 mbs)
Maxim (iButton) builtin: Value:0x78, Time: 2213 us (3.70 mbs)
MODBUS FastCRC: Value:0x2487, Time: 336 us (24.38 mbs)
MODBUS builtin: Value:0x2487, Time: 2337 us (3.51 mbs)
XMODEM FastCRC: Value:0x190E, Time: 339 us (24.17 mbs)