Memblers wrote:
I found a schematic someone made of the NES Advantage controller.
http://forums.benheck.com/viewtopic.php?f=2&t=42458
I don't think that schematic is right. One of the inverters appears to be drawn backwards.
This is the typical connection for this style of oscillator:
http://www.aaroncake.net/forum/uploaded ... llator.PNG
Also, that 120uf capacitor seems awfully high to me. I'm guessing 1uf might be more correct, or possibly 10uf at the outside.
If you don't want to have a turbo on/off switch, and would like a "normal" and "turbo" button (like on that controller) this is possible too by using an NPN transistor across the regular "A" (or B) button, with emitter grounded, and the base connected thru a 10K resistor to the oscillator via the turbo button.
As an aside, that chip in that microgenius controller is an ASIC and is not a standard part. It probably has an oscillator of some form built in, or else it just has a 2 bit or so binary counter on the load line so that it can toggle the button state every 2 or 4 or even 8 frames. That'd negate the need for an oscillator all together.