The Yamaha C1 was released in 1987 and is basically a 80286 processor
based PC with 8 built in MIDI ports for use in applications where there
are many MIDI instruments to address.
By 1987 some machines which were capable of responding on multiple MIDI channels were appearing, and some earlier machines could only function in "omni" mode which meant that they needed a whole 16 channel port to themselves or they would play every time a note intended for another instrument was sent.
Since MIDI information is fairly 'slow' in respect to what even a about 10Mhz computer can handle 8 output ports with buffers wasn't a difficult thing to pull off for even an old 286 apparently.
Various DOS applications were included, among them the Voyetra Sequencer which was set up to run all 8 ports.
Contributors : Bob Weigel (picture, info), Gareth Qually (info, specs)
Javier Z. reports:
Yamaha C1 Music Computer was used by Kraftwerk in "Electric Cafe".
We need more info about this computer ! If you designed, used, or have more info about this system,
please send us pictures or anything you might find useful.
BUILT IN LANGUAGE
88 keys with numeric keypad and arrow keys
switchable clock 10/8 MHz
640 Kbytes main, 512 Kbytes extension
40 or 80 columns x 25 lines
CGA, 640 x 400
Monochrome blueish LCD display
SIZE / WEIGHT
394(W) x 382(D) x 82(H) mm / 8.2 kg (18 lb 2 oz)
Time Code In, Time Code Out (both via RCA ports), 2 x serial ports, Expansion Card Slot, 8 x MIDI OUT ports, 2 x MIDI IN ports, 1 x MIDI THRU port, Digital RGB out port, CGA or Monochrome (Hercules compatible) mode
BUILT IN MEDIA
3.5'' Floppy disc drive (1.44 MB) + 20 MB hard disk