[Coco] Speech Systems Symphony 12 & Piano attachment

[Andrew Ayers]

If I had to guess, the cartridge with the ribbon cable probably did 
attach to the piano keyboard...but the cartridge that had the DIN was 
likely a MIDI input cartridge; I'm not a musician or anything like that, 
and only briefly played with real MIDI stuff in high school (circa 
1990-91) - but I seem to recall that everything MIDI back then (and 
probably still today) used DIN plug cables.

So the cart with the ribbon cable was just a basic kind of keyboard 
interface, but the keyboard wasn't MIDI; but I bet at some point (again, 
pure guessing) that Speech Systems either did away with the the "raw 
keyboard" design, and found a keyboard that output MIDI, or they put 
circuitry inside the raw keyboard to turn it into a MIDI output 
keyboard, or they just stopped selling the keyboard with the cart, 
making it optional (if they didn't drop it completely).

The latter seems really possible, as it would be more likely that anyone 
who wanted a MIDI cartridge for the CoCo likely already had a keyboard 
with MIDI output, or full MIDI (IE, both input and output/pass-thru 
ports; IIRC, MIDI is a daisy-chain I/O bus?).

Andrew L. Ayers
Glendale, Arizona
phoenixgarage.org
github.com/andrew-ayers