Max LED number is 255

[neo77777]

Hello
I have an issue that when I set the number of LED's above 255 in "#define NUM_LEDS 240" the LED's will not light anymore
It is working fine with 255 and under
but if I go to 256
I still get the RGB flash at the start but no light after that
I'm using Prismatik (unofficial) 64bit and WS2812B LED's
I have also tried to use "FastLED.h" V 3.1.3 and V3.3.3

[philibertc]

Hello @neo77777,
Yes, this is a limitation of Adalight, I will try to find an article on the web explaining this.

[gabekerchner]

@philibertc Any updates for that? I need use with 374 Leds

[philibertc]

Hello,
according to this forum, this program should work fine up to 500 leds. There are some explanations.
Best Regards,

[Ekristoffe]

in the code there is:
for (uint8_t i = 0; i < NUM_LEDS; i++) {

The loop can only goes up to 8bit encoded (255), change the line for
for (uint16_t i = 0; i < NUM_LEDS; i++) {
to enable more than 255 led.

[sebaschan001]

This! Thank you!
It finally it works. Almost bought a new Arduino just to rule out a bad board.
Why is this not documented anywhere? Is it that rare to use more than 255 leds?

[Ekristoffe]

This! Thank you! It finally it works. Almost bought a new Arduino just to rule out a bad board. Why is this not documented anywhere? Is it that rare to use more than 255 leds?

I think when the system was made the screen where small and 255 led was ok. Nowadays having but screen is normal … especially if you are using it for a wide screen and a lot of small led.