The '''U'''niversal '''S'''erial '''I'''nterface '''f'''or '''A'''mstrad '''C'''PC (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.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]].
[[File:Https://www.cpcwiki.eu/forum/amstrad-cpc-hardware/usifac-iimake-your-pc-or-usb-stick-an-hdd-for-amstrad-access-dsk-and-many-more!/?action=dlattach;attach=34008;image|thumbnail|USIfAC II]]
The board allows for TTL serial output and connection to a USB Stick as well as a ESP8266 WIFI module. The board has been used for many purposes including running games from Usb Stick, MIDI, RS232 and accessing online BBS.