ESP8266 Community Forum

- Tue Dec 22, 2015 7:59 am #36956

With an ESP-01 you only option is to use I2C I/O expanders such as the MCP23017 or PCF8575 (or PCA9685 if you need PWM dimming).

With ESP modules that have more GPIOs, there are more options like:
- charlieplexing basically comes for free, you can drive 20 LEDs using 5 GPIOs, but addressing the LEDs is a bit complicated. See https://en.wikipedia.org/wiki/Charlieplexing
- using 74HC595 shift registers. These are really cheap, easy to interface and can be driven at high speed using the SPI port.

Interesting!
Charlieplexing looks way out of my league (for now).

The other option seems interesting and more in the line that what I was looking for. I will look further for that option.

Thanks!

- Tue Dec 22, 2015 8:42 am #36957

Hi, if you can use WS2812 LEDs it's easy.
https://www.adafruit.com/category/168
https://github.com/adafruit/Adafruit_NeoPixel

Thanks,

As a matter of fact I ordered a bunch of independent Neo pixels a while ago, just to test things out. I am getting them tomorrow. But, with independent ones, would I be able to do this? Note that they are not chained one to another. For what I want to do (put leds in different places in a very big frame... maybe it's not an option no? (I am a complete newbie in electronics, so maybe I missed something).

I do not see the issue here... either you connect normal independent LEDs to the ESP (using an I/O expander or a shift register), or you connect a string of addressable LEDs connected in series.