Scanmatrix 8x8 interface adapter for Fatar DF lower contacts
adapts Fatar DF key contact system to 8x8 scanmatrix MIDI encoder input headers
utilizes the LOWER contacts of Fatar keys (since Fatar manuals are velocity-sensitive, they have two contacts per key, the upper being actuated at 10% of key travel and lower being actuated at 80% of key travel, while non-velocity MIDI encoders need only one contact per key)