The Morley User/MIDI/Analogue interface for Acorn Archimedes provides a User port, MIDI IN/THRU/OUT and a 4 channel A to D converter.
The User port uses one half of a 6522 VIA chip clocked at 2MHz. The User Port on a BBC Micro also used a 6522 VIA chip but it was clocked at 1MHz.
The card shipped in two versions, one like this had the full User Port, MIDI interface and Analogue port enabled. The other only had the User Port and Analogue interface enabled and was not supplied with the U1, U2 or U3 integrated circuits or the MIDI port connections on the flying lead. The EPROM on the User Port/Analogue only version was labeled as Morley Electronics