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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.
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.
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.
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?
