Will this work?

**Ryann** · 03-09-2010, 04:32 AM

Gday evryone, just a quick sort of overview of what im planning on doing. im going ahead with this, but would like a few experianced eyes just seeing over this sketch to see what i can maybe do better.. or if this will even work.

Basically want to control 12v relays with a old nes controller im going to hack. i was basicly thinking i could run 5v through the controller to trigger relays as ive shown below... problem is im not sure how i can get the 12v down to 5v to run through the controller.

Anyways im sure everyone hates on me for not knowing what im talking about, i know a little logically but dont know the nitty gritty that all you guys have the knowledge off. anyways have a look if you like.. thanks Ryann

**coreyspeed** · 03-09-2010, 04:38 AM

helps if we can see the image

**Ryann** · 03-09-2010, 04:53 AM

damn, loads up on my screen here. my connection im on at the moment is a temp. 3g connection off my nexus one, doesnt work the greatest.. ill do my best to get it online somewere else

**justchat_1** · 03-09-2010, 05:24 AM

Originally Posted by Ryann

problem is im not sure how i can get the 12v down to 5v to run through the controller.

You're looking for a 7805 regulator...should be able to find them at any local electronics store or even ebay for about $1.

**Rob Withey** · 03-09-2010, 05:38 AM

Originally Posted by coreyspeed

helps if we can see the image

Cut and paste the link into a browser: http://onsills.com/onsills08/phpBB3/...2633&mode=view

**Civic Modz** · 03-09-2010, 05:40 AM

Why don't you connect one end of all the control pad buttons to +12v and the other end of the switches to the inputs of a 2803 darlington driver chip. This chip has 8 inputs and outputs. The inputs are low impedance so you can connect the switches directly to the inputs. You can then connect the relays directly to the outputs.

This way you wont even need to have a 5v regulator

**Ryann** · 03-12-2010, 02:16 AM

Can u expand a little on that above, im pretty novice at this..

i wasnt sure i could run 12v thru the nes controller without ruining it? why couldnt i just run 12v straight thru it to my airbag solenoids? or would that fry things? the 8core im using it rather small..

whats the advantages to what your suggesting above?

sorry for being so novice here guys. im learning more evryday

**Ryann** · 03-12-2010, 04:26 PM

bump

**justchat_1** · 03-12-2010, 05:22 PM

you need the relays....taking those out of the equation is a good way to start a fire.

Civic Modz was saying that you don't need 5v to drive the relays you can use 12v. Same diagram (using the relays) just no need to step down to 5v.

**Civic Modz** · 03-13-2010, 02:14 AM

The only problem I can see is that you will have an issue powering the relays directly though the buttons. The on resistance of these button can be quite high and is unlikely that they will power the relays directly. In this case you will need a seperate relay driver such as a transistor or the ever so popular ULN2003. You might also need to debounce your buttons, but that really depends on the device you are trying to control with the relays.

About running 12v through the nes controller, are you just simply applying power to the buttons, and not the internal circuit (if there is one).