Does anyone know how the crc-16 algorithm used by SYS(2007, string) works?

I need to code an identical function in another language (Installscript!) that must return exactly the same values as the VFP function does.

(I have seen previous threads on this subject pointing to knowledgebase article Q101289 and a Dr Dobs magazine article of 1986 but both are no longer obtainable on the Web)

Many Thanks

Richard