1 octave keyboard wiring problem

[choklitlove]

i'm altering a yamaha and a set of organ foot pedals to let these pedals control the lowest octave.

i wired it and everything, and i was very optimistic.

here's the problem:
each key has an individual "lead" or connection. then, c# through f# has 1 connection that connects to the individual note's lead to make that notes sound.

what would make all c# through f# sound when any one of them is played (connected)?


hope this makes sense...

[choklitlove]

here's the board i'm working with:


the little black pads are where the keys (on the keyboard) connect the two to make that note's sound. i don't know if this picture helps anyone, but i'm at a wall.

anyone?

[toppobrillo]

im alittle confused as to waht your question is exactly.. you are trying to convert your yamaha kb to become a 1v/oct controller.. i just did that see the thread 'keyboard controllers' by me.. it was a yamaha also, actually..

i assume you are looking to use this in conjunction with a scanning digital key encoder circuit yes? if you dont know what i mean, then i guess i understand why you are confused- see the one on Music From Outer Space, for instance, this is a very standard circuit, but ray wilsons circuit description may help you understand it's operation better, there is no point in me doing that here... also, you can look at PAIA's 8700 series keyboard controller.

oh, as for your foot-pedals, see ken stone's controller circuit [4x4] based around an IC [74c922 i think] intended for this.

ok, so the keyboard i used was originally wired as a 6x6 matrix, meaning, 6 notes x 6 half octaves. to follow this type of design architecture: scanning the keyboard sequentially and operating the D/A in step from the counter, it was necessary to re-wire the keys and busses to something exponent of 2. 32 keys = 8x4 = 5 bits, does this make sense?

so, it is left up to you to re-wire your keyboard to be compatible with this type of system, or, come up with logic to use a 6x6 or build one a different way with alot more [or conceivably, alot less..PIC or other MCU] parts.

anyways, hope this helped maybe at least clear things up...
if you are going to rewire it, the only advice i have is to think it through before you start, mine had alot of little extra holes here and there that were handy. good luck!

anymore questions i wil try and help.

josh

[choklitlove]

[choklitlove]

couple more pics

[toppobrillo]

ooooooooh sorry bout that! i just assumed that you were making a controller for music synthesizers. maybe someone else wil get somethi8ng out of that.

well for what you are talking about, just look at how the keys on the keyboard are wired, and do that to your pedalboard. it will involve one diode per pedal and some wire.

[choklitlove]

thanks for the reply.

i already hooked the keyboard to the pedals, and the diodes were on the board. it's almost working...

[choklitlove]

this might help me explain a little better.


when any of the keys connected to "Common Lead" 2 are pressed, all of the notes connected to "CL" 2 play. this shouldn't happen. does my problem make a little more sense now?

[choklitlove]

this also might help:

[toppobrillo]

wait so buss 3 keys work properly?

[choklitlove]

nope. but i figure if i get 2 to work, i can get 3 to work as well.

just for simplicity's sake. this shit is hard enough to explain.

[choklitlove]

anyone have any suggestions?

[toppobrillo]

all i can tell you is that your switches should make a connect between the cathode of each note they represent and their respective bus[ses]. look at the switches in your pedal keyboard more closely.. perhaps they are DPDT connected to a common bus themselves? that would explain it. good luck with it..

josh

[choklitlove]

thanks for all of your help. i finally got it to work. of course, it turned out to be something pretty stupid, but not that stupid.

anyway, i'll post pictures as soon as i make it look nicer.


thanks, again!