Hi everyone,
I’m trying to get a WS2815 LED strip working with an Arduino Nano ESP32, but I can’t get it to light up.
The strange thing is that with an Arduino UNO, using the exact same circuit and sketch, everything works perfectly.
Here’s my setup:
- The WS2815 LED strip is powered by 12 V.
- I’m using a DC-DC converter to step down to 5 V, which powers both the Arduino Nano ESP32 and a SN74AHCT125N buffer.
- The data signal goes from pin 2 of the Arduino through the buffer (to shift from 3.3 V to 5 V) and then to the D pin of the WS2815 strip.
- All GNDs (Arduino, DC-DC converter, LED strip, and buffer) are connected together.
- I’m using the FastLED library.
- I tested the buffer: when I apply a fixed 3.3 V input, I get 5 V output, so the level shifting seems to be working correctly.
The problem is that when I upload the sketch to the Nano ESP32, the LEDs stay completely off.
With the Arduino UNO, the exact same code and wiring work perfectly.
I also noticed that during the compilation and upload process in the Arduino IDE, it shows “Done uploading”, but I suspect the code might not be running correctly on the ESP32, or the compilation may not be fully compatible.
I’ll attach:
- the full sketch,
- a screenshot of the Arduino IDE right after uploading,
- and a photo of the circuit.
Has anyone experienced something similar with the WS2815 and Nano ESP32?
Could it be a timing issue, a FastLED configuration problem, or maybe an incompatible data pin on the ESP32?
My Code
#include <FastLED.h>
#define NUM_LEDS 79
#define DATA_PIN 2
CRGB leds[NUM_LEDS];
void setup() {
FastLED.addLeds<WS2815, DATA_PIN, GRB>(leds, NUM_LEDS);
FastLED.setBrightness(180);
}
void loop() {
fill_solid(leds, NUM_LEDS, CRGB::Red);
FastLED.show();
delay(1000);
fill_solid(leds, NUM_LEDS, CRGB::Blue);
FastLED.show();
delay(1000);
fill_solid(leds, NUM_LEDS, CRGB::Green);
FastLED.show();
delay(1000);
}
IDE Screenshot
Arduino Nano ESP32 Circuit
Arduino UNO Circuit
