The Digital Keyboard Scanner....

[Hallgeir Helland]

I wrote:

> blah blah blah.... <snip>
> Praps someone will care to send me the replys
> over again (pleeease....), maybe privately?

Thank you Edu Silva & J. Harry Hendry for filling
me in. :-)

Here's a follow-up:

Paul Schreiber mentioned using 74HC151's and a clock.
This is <g> exactly what I did on my first 13-note basspedal
thingy that I now use together with the ASM-1 as a bass-
pedal-synth. Works fine except it got bugs: when key (pedal)
was released sometimes one bit of the binary code feeding the
R/2R ladder D/A would change, so I got a different note on
the Release. Annoying. Not bothering to debug, I wanted to
make one *without* any clock and counter. So I found the
4532 8-input priority encoder, and now I've designed a nice
circuit with this chip. Haven't built it yet, but I belive it'll be OK.

But, being an adventurus chap, I now hoped to be able to make
a polyphonic one...... I'm not shure anymore. The idea was to
use an analog MUX and make a sort of arpeggiator by cycling
thru the different CV outputs..... and maybe later make a complete
polysynth (maybe with CEM chips) ... but still I haven't settled on
anything yet.     I have two 44-note keyboards from an old Solina
organ, so maybe I'll start off with the mono keyboard, and prehaps
try and stuff together a ploly keyboard later.

But are the schems for, say, the P5 or the eight-voice keyboards
available anywhere? (Just *had* to end with a question, right :-) )

Thanx,
Hallgeir

BTW: I'll be checking out the Elektor Polysynth on Sponton's page.