Addressable LEDs

[botcrusher]

As i understand it, the most common addressable LEDs use those lovely ws2182 chips. Slight problem: since at the end of the day, each led effectively contains 3*8bit registers, and the clock/data lines are one and the same, won't i run into an issue where I can't pump out all the lights at the same time? I need one microcontroler (preferrably an atmega328?) to control at minimum 10m of led strip (300 lamps, 3 bytes per lamp, 900 bytes per update,  30 updates per second... 27000 bytes per second)
10m happens to be the length of our stage rigging bars for no good reason...
If using these self clocking three pin lights are out of the question, can anyone point me in the direction of how to drive these fast enough or help me with some of the veritable unicorn 4 wire (5v,dat,clk,gnd) strips i hear whispers of every now and then.

[matseng]

If you're more into using and creating the lightning patterns rather than tinkering with electronics and low level coding you might want to have a look at https://github.com/scanlime/fadecandy controller board for an excellent piece of hard- and firmware that will make life easer and prettier...

[viperidae]

About 5 seconds of google found FastLED
https://github.com/FastLED/FastLED/wiki/Parallel-Output
Supports 8 strips of WS2812 in parallel, so you're not driving 300 LED's serially, you're driving 37, 8 at a time.

Edit: regardless, it only takes 10ms to write to a string of 300 WS2812's

[tszaboo]

The way I understand it, those WS2818 chips are PITA to use, because of the timing. It is not an issue if the goal of the micro to drive those, otherwise you need interrupts. There is another type, APA102, which has clock input, so any* frequency bit banging is ok.
Just my 0.02 EUR .

[botcrusher]

Fast led looks nice, but eh, slight issue. I can't for the life of me find how many i can bloody well drive at once XD

[Dinsdale]

It should take roughly 270mS out of every second to refresh your serial LEDs.
(There is some "wiggle-room" in the timing, and it depends on the driver code what the exact timing will be).
If this is too much time or not depends upon what else your code is doing (your time budget).
Just be sure to use the right addresses.

[botcrusher]

Well, while the apa102c is very nice, It's incredibly costly compared to the ws chips. It would actually be significantly cheaper for me to buy an arduino pro mini clone for each 60leds (the amount used in the first fastLED tutorial) than to drive 30 apa102c LEDs...