DPDT ON/ON Switch Functionality Inquiry

Hey guys,

So I'm planning to do the overclock mod on my Sega Genesis Model 1, and I have a DPDT switch prepared to switch between stock clock speed and overclock clock speed for the Genesis.

But I also wanna be able to do this mod in such a way that I can use a bi-color LED to designate that RED means stock clock, and GREEN means overclock.

Here's an image to start:



In this diagram, I would connect the leg of the bi-color LED for RED light to pin 1 of the switch, pin 5 would receive the opposite leg for GREEN light, and pin 3 would receive the voltage necessary to power the LED.

For pins 2, 4 and 6...4 would be connected straight to the lifted pin 15 of the 68K CPU, and pin 2 would be connected to stock clock speed, and pin 5 to overclock clock speed.

However I then see this diagram:



This diagram indicates that pins D and C are connected, pins A and F are connected, while pins B and E are not.

I'm not sure what to believe here. I have decent soldering skill/experience but when it comes to electrical engineering I'm still very new to the game.

I'm hoping to know whether or not I should use a DPDT switch for this goal, because I'm afraid of potentially applying voltage to the clock speed pin of the CPU, or providing clock speeds to an LED.

Thanks for reading this guys.

- BlashyrkhMR101

 

that diagram for the motor direction doesn't show C and D connected, and A and F, it shows that you have to connect them to make that circuit.

 

Then I should go by the first diagram?

 

...the first picture is a pinout of the switch, the second pic is a schematic for using the switch to reverse the direction of a motor.

 

The way you described how you plan to wire the LEDs and CPU clocks is correct based off the Switch schematic and don't forget resistors for those LEDs.

 

Use a common anode (positive) led, and switch the ground (negative) connection using the switch.
Switching the positive through the same switch as the high frequency is being switched may cause issues.

I ended up not even directly switching the crystal frequencies using the switch, as it's really not the correct way to do it, and can cause issues.

If you're switching the negative using the switch, you can simply get the positive side for the led from the original led wiring, which already has an OK resistor in series, on the circuit board.

 

Thank you very much Helder.

AmmoJammo, thanks for the information, I would ensure the console is off before switching frequencies, but if that's not the right way to do it, what would be a better way to switch between clock frequencies?

 

Its not about whether or not the console is turned on, its about the interference that may be induced into the wires by using the same switch to switch the positive wire to the led, instead of the negative.