charliesixpack:
Why assume that the led data comes from ram? Why not generate the data from an algorithm?
Well, I could be wrong, and am admitedly not as familiar with FastLED as I am with NeoPixel, but I think both libraries update your strip as a single action from an array in ram. There's no option to feed in the values one at a time using these libraries as fas as i know.
Controlling these strips without using a library is possible, as mcnobby discovered recently, but this is not a great option for a newby.
In this case its an academic question, the OP's string will be around 300 leds, so Uno will have enough ram.
Cheers for everything on here.
Its good to see an awesome amount of knowledge!
Does anyone know where I can get WS2812's that are pre-soldered? I need leads that are about 600mm long coming from them. otherwise its going to be alot of soldering 300 odd of these LEDs!
Adafruit sell some like that but I suspect the leads are nowhere near 600mm. Also not the cheapest available, and the viewing angle may be narrow because of the 5mm packaging.
From the perspective of speed the WS28xx really suck. With 256 leds connected to one data line you get arround 120 fps. With a shorter chain allowing you to push less data the update rate is limited to arround 400 fps before flickering starts.
So it depends on the animations you are going to run, if that is enough for you. If not, consider getting the new APA-102 controlled leds instead, they are really fast.
Daniel Garcia: "APA102 first speed run reports. With a strip length of ~100 leds, I can run them at 20Mhz. More than that, I have to go back down to 12Mhz. I can run 360 leds at 12Mhz quite happily though.
What does that translate to in real numbers? How about Cylon, with all delays removed, 360 leds, running at 930 fps. (~90 would be the best you could get w/WS2811)"