[sdiy] How to add MIDI IN to an old Casiotone 101

[Tom Wiltshire]

Yep, that'd do it. Some of the Korg Poly6 MIDI boards work this way. Using the processor to turn on analog switches (4066) in parallel with the keyboard allows you to have both MIDI and local control at once, if that's important. Otherwise, like you said, you could manage without.

http://www.acc.umu.se/~amber/Poly6/stuff/mpx61.GIF

On 29 Dec 2013, at 11:23, Jack Jackson <jackdamery at hotmail.co.uk> wrote:

> I have this old board, it's provides quite basic digital sounds from an NEC D990G chip. As far as I can tell, this chip also performs the matrix scanning of the keybed.
> 
> So if one were to add MIDI to it, this is how I envisage it:
> 
> 1. MIDI note-on message received 
> 2. Microcontroller interprets note and uses a look-up table to tell it which position of the matrix this note fits.
> 3. Microcontroller waits until the switch for the notes row goes high
> 4. Microcontroller sends the correct pin high for that note.
> 5. Pin stays high until note-off is received.
> 
> So the micro would have to sync (or at least follow) the onboard chips scanning and just output the 5v for that note at the correct time. 		 	   		  
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