The Universal Serial Interface for the Amstrad CPC (USIFAC), currently in version 2 (Styled USIFAC II), is a modern serial interface based around a PIC microcontroller designed and built by [[ikonsgr]] from the CPCWIKI Forums.
Project's Main Thread:- https://www.cpcwiki.eu/forum/amstrad-cpc-hardware/usifac-iimake-your-pc-or-usb-stick-an-hdd-for-amstrad-access-dsk-and-many-more!/There is also a special thread for technical problems & support: https://www.cpcwiki.eu/forum/hardware-related/usifac-ii-technical-problems-support/
The only chip on the board is the 18F47Q10 PIC. The PIC software is written in Great Cow Basic and has been released by [[ikonsgr]].