Awesome custom MIDI controller beast

Young Monkey designed back in 1988 this monster MIDI controller for the Commodore 64. The Hammond d'Eggs controller was designed specifically for use in live performance. It was easily disassembled for transporting and storage. The keyboard was removed from the Hammond Sounder and wired such that it was easily moved back and forth between the two units in a few minutes. The drum triggers were made from film cans, stuffed with pieces of blanket to deaden the sound.

61 trigger switches (37 keys, 24 drums) were connected via this custom Commodore 64 parallel port interface. The port's 8 data lines were configured as 4 outs and 4 ins (8 bits). The 4 outs selected one of 4 '1 of 16 multiplexers', each capable of scanning up to 16 triggers (a maximum of 64). The 4 ins (4 bits = 16 triggers) returned data from these multiplexers. The board is shown here without the multiplexer chips.

Custom designed software on the C64 performed MIDI routing to as many as 16 different MIDI devices (percussion and synth). Each switch was scanned in succession by a looping machine code routine. Because of the design, no two switches could be triggered at exactly the same time, but the system ran fast enough that this was rarely a problem. At any time, triggers could be re-routed to a different MIDI device and/or sound. Routing patches could be created and saved on the computer. Loading of patches could be initiated from any of the Hammon d'Eggs triggers. The unit supported up to four sticks simultaneously.

He also built other custom Commodore 64 projects, like his custom MIDI interface, a weird looking analog percussion synthesizer and a speech sinthesizer. Not bad huh?

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