Okey, I originally posted this on http://www.edaboard.com
because it has nothing to do with Arduino, but as I couldn't solve it there and I think that Arduino forum has a lot more activity than the other one, and also there is a lot of people here that knows this stuff very well and helped me in the past. So I tried posting it here.
Thank you very much for taking the time to read this and help me!
I designed this circuit which I think is a pulse generator, made with a 555 IC, counter and an inverter to generate a ryhtm for the drum machine
Out of the picture (down) is a hi-hat circuit.
(those two things drew on the right by hand are buttons)
First of all this part is working fine, it generates a desired pulse and is having no problems by itself, also the hi-hat works fine in rhythm.
I also made two PCBs for this circuit:
which generate the snare and bass sounds and connected each one (bass and snare triggers) to the designed pins on the right of the first image. That also works fine by itself with the rhythm.
As I also want the drum and snare to be triggered by a button when the snare and bass rhyhtm is disabled (by disconnecting the switch on the right of the first image, next to the snare and bass rhythm output pins, labeled "X2_RITMO(OPC)") so I also connected a button to +9v and the other pin of the button to each trigger and THATS WHERE THE PROBLEM IS.
When I press the bass button it first triggers a bass drum sound, but when I realease it it makes a snare drum sound, also it seems that the snare button doesn't trigger the snare at all.
On the other forum a user kindly suggested I should put a diode in the bass wire, so that none of its switch action gets back to node 3.
So I made this modification:
but now it behaves in a weird fashion, when I press the bass button it makes the snare sound like a machine gun firing it very rapidly.
Any ideas what I could try? Thanks a lot!!!