Hi, how exactly can I set a variable for preset colors?  I'm trying to

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1

Hi, how exactly can I set a variable for preset colors? I’m trying to do something like this.

Variable = CRGB( 255, 90, 0)

But when I reference the variable in the program, it doesn’t seem to work, It doesn’t light up the led at all.

2

What method are you using to turn your LED(s) on in the color you defined?

Try plugging your preset color into the fill_solid function:

fill_solid(leds, NUM_LEDS, Variable);

…where “Variable” is the CRGB color you referenced in your post. This should set the value of each LED to your desired color and ‘show’ that color with a single call.

3

Forgive me, I’m pretty new at this and mostly learning from samples.

Originally I was using this in a for loop

leds[i] = CRGB( 255, 90, 0);

I could probably use the fill_solid with the number of leds instead of using a loop.

But how exactly should I define the variable?

I tried this

int color = CRGB( 255, 90, 0);

But it doesn’t seem to work.

I just tried that with

fill_solid(leds, 1, color);

and it didn’t seem to work. What might I be doing wrong?

4

Assuming your hardware is properly configured (with the necessary corresponding definitions/declarations in your code), then try this and see if your LEDS light up:

fill_solid(leds, NUM_LEDS, CRGB(255, 90, 0));
FastLED.show();

5

Using that works, but if I try to use the variable, it doesn’t seem to work.

6

Instead of

int color = CRGB( 255, 90, 0);

try this:

CRGB color = CRGB( 255, 90, 0);

Your variable isn’t an int. Its a CRGB color. This should help.

7

I don’t know why I didn’t think of that! Thank you, that works.

I guess I was just thinking that because you could also use hex that int might work. Told you I’m new to this. Lol

8

Well, you could also use an integer, but you need a wider one to hold all the bits of a color. On AVR-based Arduinos:
“int” is fifteen bits plus a sign
“unsigned int” is sixteen bits
CRGB needs 24 bits (8 each for R G and B)
“unsigned long int” is 32 bits
“uint32_t” is a shorter way to type the same thing

So you could use uint32_t, but at 32 bits, that’s actually bigger (and slower) than the 24 bits that it needs to be. “CRGB” is actually smaller and faster than an integer in this case!