Replace RGB plate push buttons with LED push buttons

EL Wire/Tape/Panels, LEDs, pixels and strips, LCDs and TFTs, etc products from Adafruit

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plopez
 
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Joined: Thu Jan 23, 2014 12:49 pm

Replace RGB plate push buttons with LED push buttons

Post by plopez »

Hi all.

I'm very new to the raspberry pi + adafruit toys world, so please excuse my question if it is awfully dumb.

I followed the tutorial for the RGB plate, and everything is up and running (yeah ;)
I was wondering if it was possible to replace the "classic" push button sold with the RGB plate with shiny LED buttons.
ImageImage
If the answer is yes, how can I wire them ? I have 4 pins to solder, numbered 1 to 4. Which one go to led power, which ones go to push mechanism ?

Next, can you provide sample python code to
- control led enlight
- detect push on the button

I'm asking before testing on my own and frying led, RGB or even Pi ;) Thanks for the help you could provide.

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adafruit_support_rick
 
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Re: Replace RGB plate push buttons with LED push buttons

Post by adafruit_support_rick »

There's no power to those buttons for lighting the LED

plopez
 
Posts: 5
Joined: Thu Jan 23, 2014 12:49 pm

Re: Replace RGB plate push buttons with LED push buttons

Post by plopez »

Hi.

Thanks for the quick reply. From what I understand, I have to use the RGB and the button on I2C - 5V, and wire the leds on GPIO 3.3 V.
Do I need to have a level shifter (BSS138 or TXB0108 ?) to protect the devices, or having different voltage on GPIO and I2C does simply the trick, wihtout any risk of backfiring ?

Thanks again ?

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adafruit_support_bill
 
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Re: Replace RGB plate push buttons with LED push buttons

Post by adafruit_support_bill »

You can run the leds off 5v or 3.3v. But you will probably need a current limiting resistor. The size of the resistor will depend on both the operating voltage and the LED forward voltage (which will depend on its color). For details on choosing the right resistor, see this guide: http://learn.adafruit.com/all-about-leds

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