Need help with Neopixel (WS2811, Wemos D1 mini)

Just won’t create a new post, so grabbed this one :slight_smile:

Hey guys,

I have a problem with setting up the Neopixels :frowning:
I have a Wemos D1 Mini with WS2811 (12 Volt) connected to it.
My 12V power supply is connected to voltage adjustment board 12v to 3.3v.
The 3.3V are connected my D1 mini. So it is powered up. I can see it in blynk and did a small test with a button and the builtin LED. That worked great.

Then I tryed this one:

#include <Adafruit_NeoPixel.h>
#include <SPI.h>
#include <BlynkSimpleEsp8266.h>
#include <ESP8266WiFi.h>

char auth = “59e6fxxxxxxxxxxxx”;
char ssid = “xxxxxxxx”;
char pass = “yyyyyyyy”;

#define PIN D2
#define NUMPIXELS 30
#define BLYNK_PRINT Serial
Adafruit_NeoPixel pixels = Adafruit_NeoPixel(NUMPIXELS, PIN, NEO_GRB + NEO_KHZ800);

void setup()
Blynk.begin(auth, ssid, pass, “my blynk server DNS”, 8080);

int R = param[0].asInt();
int G = param[1].asInt();
int B = param[2].asInt();
for (int i = 0; i < NUMPIXELS; i++) {

pixels.setPixelColor(i, pixels.Color(R, G, B));;


void loop()

I can do what ever I want with my Zebra in blynk that is connected to V2 (Merge)… nothing happen on the LED. The data Input of the LED (green wire) is connected to D2 on the Wemos. I also tryed #define PIN 4 (nothing changed :().

What am I doing wrong? 12V are present on those 12V junctions on the LED strip.

I’ve moved this to it’s own topic. Feel free to edit the title if you wish.


I managed the problem by myself. Just the first element of the WS2811 was broken.
But now I’ve got a new problem :confused:

If I extend the wire between my pixels and the wemos d1, the led starts to flicker. Is there a possibility to extend the wire to 2.5meters without the flickering?

power supply >>>>>>> 1m cable >>>>>> Wemos D1 Mini >>>>>> 2.5m wire >>>>>>>>> WS2811