How to make a BiColor LED change colors?

[sjaltenb]

On a Bi-Color LED, how do you make the color change? How are they hooked up?

I ask becuase I want the following:

Two effects will have a total bypass and a selector switch to select between the two. I want there to be two total LEDS.

I would like, when the whole thing is bypassed, for the effect that is "up to bat(selected to come on)" to be Green, and then when i turn the effect on with the total bypass switch,  I want it to turn RED.

Can this be done?? Thanks!!!

[iaresee]

Depends. How many leads on the package? If it's three leads it's either a common cathode (I've only ever seen these) or common anode (they exist, I've never encountered them) configuration. Assuming common cathode you connect the common lead to GND and use a switch to send one of the anode leads to +'ve and disconnect the other one. If it only has two leads it's bi-polar (also popular, I've never seen them used without logic gates): one colour when current flows one way, the other when you reverse the direction of current flow. See: http://www.play-hookey.com/digital/experiments/bicolor_led.html -- for an example of wiring up a bi-polar, bi-colour LED.

[sevenisthenumber]

just use any type of "triple pole" arrangement.

On the far right poles were this shows an led arrangement just ignore what it says and do this:
the right leg of led goes to the top post of the switch, left leg goes to bottom post of switch. send your power (9v) to the middle post of switch (you better put at least a 2.2k resistor on it or it will fry the led). send the middle leg of led to ground.
Good luck!
!

[amz-fx]

Look in my blog for a way to wire up a 2-pin bicolor LED.

regards, Jack

[sjaltenb]

ahhh thank you..

but now how could i implement that design into what i'm doing with the master bypass and A/B Selector??

I really did sit down and think about this for a long time, I just cant figure it out!!

Please help, it would be a really cool/useful addition to my board.


I want whichever effect (a or b) to have a green light when "ready" and then turn to red when the total bypass is engaged...

Thank you!!