This keyboard display has an RGB LED for each key that is addressable through the common stage lighting protocol, DMX. The project video, seen after the break, does a good job of walking us through the concept. By using a MIDI to DMX converter box [John] can show MIDI signals coming from a keyboard on the appropriate key of the display. By further monkeying with the firmware in the converter box he shows a plasma effect on the whole keyboard, making the corresponding light for each pressed key pop out in bright white. Jump to about 3:45 to hear and see “Sweet Child o’ Mine”.
This isn’t the first time [John's] been caught with a slew of blinking lights. He helped create the giant LED Christmas tree that brightened up our holiday.