For folks using the FastLED (formerly FastSPI_LED/FastSPI_LED 2) libraries. * PLEASE READ BEFORE POSTING *
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Daniel Garcia

Releases and Announcements  - 
A handful of administrivia things:

* Because of a recent death in our family, +Mark Kriegsman and myself are going to be stepping back from FastLED for a little bit. One of the things we love about this community is how helpful all of you are with each other, and we're extra thankful for that right now. There's more in Mark's post here:

* In light of the above, +Jason Coon offered to help out with moderation here, so I've bumped him up to moderator to help out with when g+ decides to auto-moderate posts.

* Also - I believe I have discovered what it is that's causing g+ to auto-moderate posts - it appears to do so when folks use pastebin for posting code. In that case, please use, not pastebin for posting code - I've updated the faq at to reflect this.

I'm going to pin this post, and will update it as we figure out more things (we haven't decided yet whether or not to add another admin to the FastLED github yet, for example).

Thank you again, everyone, for your support, for being a fantastic community, and for all the light.
John Benoit's profile photoChristophe Lallement's profile photo
Take care. I join my thoughs to all your family. 
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Hi all. Is there an easy way to change the order of leds in a CRGB array?

Basically I have 8 led strips daisy changed together, arranged in spokes. I'd like to to change to order the spokes are arranged, but in software, and I only need to do it once.

[ 0-9 , 29-20 , 10-19 , 39-30 ....]

I feel like I'm missing something simple
Tod Kurt's profile photoAndré Geldenhuis's profile photo
+Tod Kurt that's great, it's nice and simple and lets you use the built in functions without having to modify them. Thanks!
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Please tell me how to do it.
How to divide the tape into multiple arrays and calls in code to specific arrays?
#define NUM_LEDS 100
NUM_LEDS_1 (0 to 30 pixel)
NUM_LEDS_2 (31 to 60 pixel)
NUM_LEDS_3 (61 to 100 pixel)
That is, I need one more virtual tape.
Thank you.
Ken White's profile photo
+Александр Бородач - What you are looking for is CRGBSet. Use the “Search Community” box on the left of this webpage to search for "CRGBSet Ken White" or "CRGBSet Daniel Garcia" to find information on what you want to do.
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Knos koloz

Support  - 
Hello all,
I used fast Led a few times already for cosplay and it works like magic :D
Now I'm trying to get fastled to run on an arduino firecricket
it's supposed to be similiar to an arduino zero but it uses a slightly different cpu called Atmel ATSAMD21E17A ARM Cortex M0+. I assume I have to add a pinlayout in fastled for this cpu but actually have no idea were to look. Is there a howto how I can add a pinlayout for a new cpu. Maybe even a copy/paste from the Arduino Zero would work.
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Marius Rauktys

Show off your work!  - 
Hi all

Just want to thank you all. Creators - for superb FastLED library, members of this group - for inspiration, ideas and support.

Below you can find my floor lamp. It was so much fun to create it. To play with blinking lights and to discover new things.
Once again - thank you all!
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I'm using FastLED to power 130 APA102 LEDs. I found an example confetti demo and modified it a bit for my needs.

I have everything hooked up like so:
-9V 1.5A power supply going into buck converter
-buck converter outputting regulated 5V
-output from buck converter going to breadboard
-two separate power outputs from breadboard: one to the arduino and another to the LEDs
-ground connections for arduino/LEDs
-data and clock pins from arduino to LEDs

There still wouldn't be enough power to drive 130 LEDs at full brightness, so I tried to control the power with FastLED. setMaxPowerInVoltsAndMilliamps. However, when I do that the buck converter starts making a humming sound. The animation seems to work fine though. It's even pretty bright, which I don't understand. I thought it would be pretty dim because of lower power.

The really weird part is when I remove that line of code everything works exactly the same.

So my questions are:

1. Why is the buck converter humming?
2. Am I using FastLED. setMaxPowerInVoltsAndMilliamps correctly?
3. If I'm not using it correctly how do I fix it?
4. If I am using it correctly, why is there no change when I remove the line?

Thanks for the help!
Andrew Tuline's profile photoJoe Meissler's profile photo
+Stuart Taylor I didn't know that, so that's reassuring. I just checked (should have done that before posting), and it's drawing no more than 1A so that's good.

Since I'm going from 9v/1.5A to 5V, would I theoretically be able to use 2.7A? Of course a little less due to the Arduino pulling a little bit.
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Vijay Kumar

Support  - 
Good morning all. i want few suggestion regarding dmx. whether fastled library supports dmx. As of now, i know how to set pin for data line for led strip. coming to dmx, how to connect to it. I searched through google and got the information that,

arduino uno -> max485(for transmitting dmx signals) ->whetever distance below 1200 metres through twisted cable (2 wire) ------> max485 (for receiving side)--> arduino uno(slave) --> ws2811 led strip.

By, using the above we can connect the n number of slaves for controlling thousands of leds in identical manner with out compromising the distance to be covered.

I need ur help to figure out, which is correct way for wiring and the library for dmx. if possible show me a sample program for it. I really need to drive thousands of leds.

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Mark Ortiz

Support  - 
Hi. I've upgraded my trusty old LPD8806 strips to APA102s. The patterns look a bit weird, and the documentation said they may be running fast and to set up as follows:

FastLED.addLeds<APA102, RGB, DATA_RATE_MHZ(12)>(leds, NUM_LEDS);

However, when compiling it fails as 'call of overloaded 'addLeds(CRGB [289], int)' is ambiguous'

What am I doing wrong? Thanks
Daniel Garcia's profile photoMark Ortiz's profile photo
Thanks Daniel.
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with advance thanks to +Mark Kriegsman and +Marc Miller for the help they've already provided with Mark's original twinkle Fox lights and Marc's mod for me for my Faux prop servers....

I've been moving along with my 'big' controller, but am looking to make a smaller, user-controllerable one...basically I need to put a handle on brightness, speed & density...MAYBE color too...

I dug thru the archives & found Mark's suggestion about adding the lines: FastLED.setBrightness(analogRead(A2)/4);
to the look to allow handles for those values, and it works like a charm...

but now I'm stuck on how to adjust DENSITY on the I guess that 'Density' isn't the actual code....or call or proper term....

so basically, I have 2 pots happily adjusting SETBRIGHTNESS and DELAY, now how do I get a line in there to adjust DENSITY?

I attempted the " int densityValue = map(analogRead(densityInPin), 0, 1023, 0, 255);" but methinks I boinked the terminology...I'm guessing there's no such thing as 'density value'?

(BTW, look out for the faux servers on BULL and THE BLACKLIST and QUANTICO this year....)

and as always, thanks for the help!

Marc Miller's profile photoMichael Sime's profile photo
+Marc Miller CORRECT...I swiped that line from another post where Mark suggested adding handles to his twinkle sketch....

I'll do whatever is easiest & most effective....basically I want my end user to have a simple way to adjust brightness, speed, density and switch pallets....

I'm away from my workbench until Sunday night though....
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Hi all!!!

I'm working on a project with Fire2012. I have 2 pots, 1 controls the brightness, which works fine. The other 1 I would like to use to control the NUM_LEDS, to make it shorter or taller.
The problem I'm running in to is is in the first part of the Fire2012() function:
static byte heat[NUM _ LEDS];

In my case it's:
static byte heat[siveVal];

"sizeVal" being the value being read from the pot.

The compiler complaint is:
"storage size 'heat' isn't constant"

I've tried several different ways to make it work, with no joy. Is there another way to declare the "heat" variable, or what should I do???

Thank you for your help!!!

Arduino Nano with WS2812B's

Tod Kurt's profile photoJames Edwards's profile photo
+Tod Kurt Agreed, NUM_LEDs is the size of the Array. And you want to manipulate the the "maximum index" into the array.
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Tommy Sciano

Discussion  - 
I am looking for some MSGEQ7 projects with fastled patters, Non matrix for single strand LED strips. If anyone has any code out there for fastled patterns with the MSGEQ7 I'd appreciate anything you post and I can browse through!

Myles de Bastion's profile photoJuergen Bruegl's profile photo
I made a simple VU-meter - FastLED_VU-Meter

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Show off your work!  - 
Fire! Wee look at 2D fire and "sun" (or fireball) effects I've improved a bit lately. Who else has done 2D fire effects? These are both done with lots of use of the noise functions but i'm sure there are lots of ways to make decent looking fire. 
Freddie Olivas's profile photoRobert Atkins's profile photo
Would love to see some 2d fire code also :-)
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About this community

Getting this off the ground - a community for people who are users of the FastLED library. This will be a place to discuss what you're doing, get help, get information about updates, etc... If you are asking for help, please include the following: * What version of the library you are using * What version of arduino you are building with (and what additions have you installed to arduino, e.g. teensy, etc...) * What OS you are building from (linux, mac, windows, something else) * Uploading code to either pastebin or gist will also help quite a bit.

Charity Stolarz

Quasi-related random  - 
FastLED found at the Women's March on Washington! I know he posted it on here before but there's barely any service in DC right now. So tag for me plz! Also sorry for vertical video... so tired...
Marc Miller's profile photoDustin Van Tate Testa (Tate)'s profile photo
Lit, wish I was there
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Knos koloz

Show off your work!  - 
A gunfire effect for a cosplay prop works good so far.
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Vijay Kumar

Discussion  - 
PaulStoffregen's profile photoTommy Sciano's profile photo
you could use Jinx or Glediator.
Here is one for the ESP8266 - rstephan/ArtnetWifi

And here is one for Arduino boards that arent wifi from Glediator

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Harald Dahl

Support  - 
I've just recently run into a strange problem that I'm not able to solve :/

In my basement I have 7x 5m Neopixel strips from Adafruit in my ceiling.
They are controlled with a Teensy 3.2 with an Octows adapter, and receives messages from an ESP8266.

Suddenly, about a week ago, I noticed something was wrong. The program/cycle that was running had stopped. The LEDs had not turned off, they just didnt update any more.
I pulled the power and put it back, and now the LEDs didn't turn on at all.

So I took the teensy+esp down from the ceiling to do some debugging. I've inserted a Serial.println("Hello world") all over my code, and everything seems fine. The teensy seemingly runs through the code exactly like it should.
It also reacts to the WIFI-messages I send, but it's not updating the LEDs.

I've also measured the voltage in several places, and I'm reading 5.1V-5.2V everywhere.

What the hell could be wrong? Any tips would be greatly appreciated.
Daniel Garcia's profile photoKeith Evans's profile photo
It might help if you said what sort of test equipment you have available. If you plan on doing a lot of embedded development in the future then an oscilloscope would be really handy to have. You can use it for troubleshooting this sort of problem, but it can be really handy to have for software development too. e.g. to measure how long a routine is take, or to monitor the execution flow of your code. (e.g. wiggle a few GPIOs.) I've seen them used very effectively by embedded software engineers working on real-time code.

Assuming that you don't have a scope or access to one, you might have a multimeter. If not you can find really inexpensive models now and I would recommend buying one. You can use it to verify connectivity by measuring resistance, but also if you wiggle GPIOs really slowly you can watch the signal lines toggle.

Also I don't see them in use much anymore, but logic probes can also be used for this. There used to be models that would capture pulses and indicate if a line was tristated as well. The only issue would be if the probe didn't support all of the logic thresholds that you're using.
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Hi guys, Ive now had the installation at up for some weeks now, and it is stable. I'm now looking into defining a XY-matrix to make better use of it.

Since it are leds running around the windows, its getting quite large for a table at 48x768px (and i might also want to take into account the space between the windows)

Are there anybody here, thats good in the math required, who can give me a hint in the right direction how to solve this.



Gustavo K's profile photoRasmus Hildonen's profile photo
The mapping for all 16 windows will be huge, its a matrix 48x768 = 36.864 entries -- where only 3008 are actual leds, the rest are just there for the mapping.
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Ryan Black

Support  - 
Just started using fast led library and the arduino a couple days ago and noticed the capacitor and resistor hook up for some led straps but I'm using apa102 and would like to know if I should add anything to it also.
Andrew Tuline's profile photo
For my small strips (both WS2812 and APA102), I just go commando, as in no resistors or capacitors. If I were to implement something with more than a foot between the Arduino and the strip, I'd reconsider that. Just make sure your grounds are tied together.
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Jason Coon

Discussion  - 
I'll see if I can get the FastLED master branch working on the Photon. :)

"Improved Arduino library compatibility: Most Arduino libraries can now be copy/pasted into our library manager without modification"
Jason Coon's profile photoKeith Evans's profile photo
I think that using the remote web server would be most appropriate for me. It's definitely a good idea to consider security carefully. If it can be made to work, then it would be nice to have a method that would work even if the particle cloud ceases to exist.
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Lumir Karas

Discussion  - 

I'm relatively new to FastLED but I absolutely love how easy it is to work with. So I started my project on a smaller 5m 50pixel 150 LED WS2812B strip with success. Now when everything is tested and working I'm ready to go bigger. So I ordered three 5m 300pixel 300 LED strips using same 5V WS2812B but am experiencing problems. Even using single strip I cannot go higher than brightness 60 when weird flickering from the other end of the strip occurs. It is very visible in pure white but it is noticeable in other colors as well. With increasing brightness the end of the strip start loosing green and blue leaving red only. I would normally think it is caused by weak power supply but I use 300W 5V 60A switching power supply outputting verified steady 5V. I try testing this eliminating all me known variables ending with single FastLED.Show() with brightness above 60 to see same result. No loops, no variable pots, just single push to lid up 300 white LEDs. I'm baffled at this point with no more ideas. I found this great live forum with hope finishing my DIY project with the new LED strips. Thank you! 
JP Roy's profile photoLumir Karas's profile photo
Thanks for the info Roy. I think I'll do it using the 12V version. I tested one and even with 3V drop on the other end all LEDs still work fine with much smaller power supply in full brightness. 
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