Arduino Forum

Using Arduino => LEDs and Multiplexing => Topic started by: sblantipodi on Dec 05, 2018, 01:49 am

Title: Ws2812b on wemos d1 mini lite
Post by: sblantipodi on Dec 05, 2018, 01:49 am
Hi, when I try to use fastled library to control a ws2812b Led strip
I got this error while loading the sketch on my wemos d1 Mini lite.

note: #pragma message: No hardware SPI pins defined.  All SPI access will default to bitbanged output

 #      pragma message "No hardware SPI pins defined.  All SPI access will default to bitbanged output"

What does it means.
Than the led strip does not work

Can you help me please?
Title: Re: Ws2812b on wemos d1 mini lite
Post by: GypsumFantastic on Dec 05, 2018, 09:13 am
It's just a warning. The developer knows it's often spuriously triggered. There's some discussion about it here on the FastLED Github (https://github.com/FastLED/FastLED/issues/438).

You can safely ignore it.
Title: Re: Ws2812b on wemos d1 mini lite
Post by: sblantipodi on Dec 05, 2018, 12:05 pm
the problem is that all the leds remains off except the first one that stucks in green.
this sketch should drive the led strips using MQTT (I'm using Home Assistant)

https://drive.google.com/file/d/1uhjC8T1-1f9JVmvwdfI1F5Z9UXeOR8NG/view?usp=sharing

is there something I'm doing wrong?
Title: Re: Ws2812b on wemos d1 mini lite
Post by: GypsumFantastic on Dec 05, 2018, 12:16 pm
People will be reluctant to follow your link.

Post your code here inside [code] [/code] tags.

Show us how your project is wired - take a clear photo or draw a diagram.
Title: Re: Ws2812b on wemos d1 mini lite
Post by: sblantipodi on Dec 05, 2018, 08:02 pm
People will be reluctant to follow your link.

Post your code here inside [code] [/code] tags.

Show us how your project is wired - take a clear photo or draw a diagram.
thanks for the answer.
code is too long and it doesn't let me paste the code in the code quotes.
it's a google link, you can trust me :)

(https://i.postimg.cc/MGBv5Ss1/pc.jpg)

in the image is shown an arduino nano but I'm using a wemos d1 mini lite using the same pin.
Title: Re: Ws2812b on wemos d1 mini lite
Post by: PaulRB on Dec 05, 2018, 11:44 pm
Have you tried uploading one of the standard FastLED example sketches to test the strip?
Title: Re: Ws2812b on wemos d1 mini lite
Post by: sblantipodi on Dec 07, 2018, 10:27 am
After hours of trouble shooting I realized that removing the resistance from the circuit solved the problem

Everyone suggest a 470ohm resistance for the data pin but if I put that resistance in my circuit no data arrives to the led strip.

All solved now.
Title: Re: Ws2812b on wemos d1 mini lite
Post by: Paul__B on Dec 07, 2018, 12:36 pm
You do realise of course, that the resistor must be where the data wire connects to the strip, not at the Arduino end?

Of course, many people manage without the resistor, especially if the Arduino and WS2812 are adjacent but it is having the LEDs at the end of a long cable where it is important.