Content originally posted in LPCWare by brik2k on Tue Dec 25 22:13:10 MST 2012
Hi,
I'm attempting to use an LPC11C24 to control a type of RGB led that has a simple controller (ws2811) built in to the led. Instead of using a clock signal the chip uses precise bit timing to recognize each incoming bit (24bits total to make 3 bytes). It varies depending on the datasheet you find but the basic idea is that a zero is sent as 250ns high followed by 1000ns low and a one is sent as 1000ns high followed by 250ns low. Essentially, the mcu needs to translate the 3 bytes in to the proper timing and then update a data pin every 250ns.
My question is, what sort of recommendations do you guys have for implementing this on an LPC11xx? Is it even realistically possible with just C code? I've already tried a timer interrupt but that appears to be too slow. I'm also working on using SPI, which works on other controllers, but seems to be a problem on the LPC because framing. Next on the list would be a tight loop that checks the timer. Ideas?
Thanks!
