5

I have a RPi project where I want to build but alas I'm a programmer, not an electrical engineer. I can solder things, but I couldn't tell you what resistor I needed to put where.

Anyway, I looked around and there's lots of led strips, but I need 25-30 separated leds that are individually addressable for my project.

I looked a lot but found nothing, I figured if anybody would know, it would be you guys.

3 Answers 3

2

You can buy a couple of MCP23017 port expanders and connect them to the Pi's I2C bus (GPIO 2/3, pins 3/5).

Each MCP23017 has 16 GPIO so that gives you 32 outputs to which you can connect LEDs. You can connect up to 8 MCP23017 to the I2C bus.

1
  • I'll give this a go. Still not sure how to wire it without burning something out but I found a tutorial that seems to do what I'm trying to do... raspberrypi-spy.co.uk/2013/07/…
    – stu
    Nov 28, 2015 at 15:54
3

In addition to @joan's answer see: Powering and controlling hundreds of LEDs with a Raspberry pi

Especially if an off-the-shelf solution is wanted, this might be worth a look: individually addressable LED strips, e.g. based on the LPD8806 (example) that seems to have a Pi library.

3

NeoPixels worked well for me: NeoPixels on Raspberry Pi

Very programmer friendly. I got everything up and running with no soldering, and the python library is very easy to use.

Separated leds, like these?

2
  • hmmm... neat stuff, though you pay what you get for. ~$1.00 an led seems kinda steep, though I don't need many of them. I ordered all the other stuff (the mcp23017) so if I can't muster the brains to make that work, I'll try this. Thanks.
    – stu
    Nov 29, 2015 at 20:11
  • you can find people selling WS2811/2812 LEDs on alibaba. for me the attraction was a ease of the API.
    – russau
    Nov 30, 2015 at 1:17

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge that you have read and understand our privacy policy and code of conduct.

Not the answer you're looking for? Browse other questions tagged or ask your own question.