Happy New Year everyone! Will FastLED work with the strip hooked up straight to

Archive FastLED Archive
,
1

Happy New Year everyone!

Will FastLED work with the strip hooked up straight to a Wemos D1 mini?
I have a short strip hooked up to the 5 volt pin and the ground on the Wemos, and data off pin D1. It does nothing.
Also, do you declare the pin “D1” or “d1” or just pin 1?

Thanks for the help

2

I believe u u have a logic level problem. Try lowering the voltage to 3.7v like you would get from a lithium ion battery then I think it will work. The Wemos D1 mini I am assuming is like the other eap8266 based boards which run at 3.3v. The LEDs expect 5v but will run on less, however to detect a ‘high’ value they use their input voltage as a reference, so when you D1 sends a ‘high’ value it will output 3.3v but the LEDs will be looking for around 3.4 - 3.6v so they won’t ever see any data from the D1.

You can either lower the voltage at which you are driving the LEDs or you will need a level shifter to bring up the voltage from the data pin on the D1

3

Also - pins for FastLED are just the number - no preceding D - otherwise it messes with mappings (also - not all the platforms FastLED supports use Dxx for pins, so it’s pretty much just universally unsupported - weird things will happen, or maybe not ¯<i>(ツ)/¯ )

4

My first code did not work with just 3. Since that i am always using D3. But i’ll try again without D

5

Yeah, it’s probably a level issue. Wemos runs at 3v3, including all GPIO. I haven’t tested, but the 5V line will likely actually output 5V when powered via USB. The 2812 strips won’t work if it has 5V power, and 3v3 Din. Either get a 3v3 power source to the strip or you need to get a level shifter like Ben said to convert the GPIO to 5V.

6

It just works without level shifter with my wemos boards and my strips when i use USB power. It fails with a 5v powersupply.

7

I’ve found that the LEDs seem to work best on pins D5, D6, D7 and D8. They normally work without a level shifter. I declare the pins as D5, D6, D7 and D8. This seems you work with both USB and external power…

8

Thank you all for the answers. I’m trying to make a set of wifi controlled candles and trying to keep the controllers as small as possible.