Fun with RGB LED Strips

I've had an interest in solid-state light sources - and all the fun things one could conceivably do with them - for some time now. Recently, I've actually had enough of a break in my absurdly insane work and home schedule to permit me to dip a pinky toe in the waters.

I've had my eye on the WS2811 from World Semi for a little while, and more recently the SMD5050 RGB SMD LED which incorporates a WS2811 in-package.

So I finally broke down and bought an RGB LED strip to give them a go (just a meter to start).

I had also recently acquired a Discovery Kit from ST Microelectronics and, since I work with the STM32 family quite a bit where I work, I decided I would use that as the driver platform (it features an STM32F407 microcontroller). I also wanted to write my own code for it - it's more fun that way. :-)

So far, I've had just enough time to get the basics of the driver working.

Yes, I know - the 'scope's a dinosaur. I haven't bothered to buy anything newer because I have access to excellent equipment at work. Besides which, when I do drag it into work with me (much of my equipment finds its way there at various points in time), I can be assured that it won't walk off. No one wants to use a 60 MHz 'scope. :-) Unfortunately, it's barely sufficient for this application, and while I'm getting the timings tweaked I'll probably have to bring things in to work with me for a bit.

Since driving a WS2811 isn't a straightforward process, I figured I would share my observations and perhaps my code as well, as I'm working on this project.

Now if I can only find another two or three hours of uninterrupted free time...