Perhaps a bit late.
but is does work.. from fx3n on there is a function called CRC but this is het crc calculation according to modbus standard. The plc has also Modbus functions, and when you use these the crc is automatically calculated and added. So mo me this CRC function will nog B3 used very often outside an Modbus command.
ik had a similar need for CRC calculation but for modem protocol, this uses another polygon number. These calculations are everywhere on the net in C languages.
I reversed engineered it and wrote this an common ladder, piece of cake and… it works.
