Hey all,So I have this awesome toy keyboard I found and I opened it up to find a fairly straight forward situation. All the keys find their way into the circuit board in an orderly fashion and I found that you simply need to supply a positive voltage of 3.3v to the key connections to make a note play. Obviously I'm thinking of making Arduino play the keyboard, which seems simple enough (analogWrite(pin, 168) ??)
but since there are 24 keys I'd like to have a driver do the work seeing as how I have so many lying around. It's my understanding though that the driver ( TLC5940 ) brings each output pin to ground, rather than spitting out voltage like an Arduino pin. How might I go about making this work?
is that just because I'm sending too much voltage from the pin? I'll make a divider next time ;p...
I always kill these things........
As for the voltage divider between the Arduino and the shift register, are you saying that I should use the normal resistor method or use a regulator?
If I use resistors (did this maybe once about a year ago) the equation is Vout = (Z2 / Z1 + Z2) * Vin which leads me to believe that I could use a 500ohm for Z1 and a 1000ohm for Z2, how does that sound?
With voltage dividers, does it matter what values you choose in the sense that, as for the equation, I could use a 2ohm for Z2 and a 1 ohm for Z1? Is it better to use higher values?
Man I need to learn about amps. They elude me.Thanks!