These are chat archives for Makuna/NeoPixelBus

Jan 2016
Jan 14 2016 17:49
ah, very cool!
unfortunately i won't be able to test it for a few months, as I'm away from home, and don't have unit where gpi03 is broken out. its a shame the pin cannot be used with ESP01....
What are your thoughts on this method? better, can drive the pixels fast, send longer strips... any advantages over UART method? just curious.
Michael Miller
Jan 14 2016 20:06
I2S method (DmaDriven branch) takes more memory, as it has to have a buffer the DMA is working off and you need a buffer your code is animating too. I will be looking at how this might be streamlined some in the future. This method also is constantly updating the bus (sending) even if you don't call show as fast as it can go (the hardware is setup to do this). Its timing isn't as accurate as the Uart for some reason I don't understand yet. Its consistent but the length of the bit is close to the minimum per spec so it might be sensitive if the crystal on your device is running a little fast; but shouldn't be a big concern as it is within the allowable error per spec. If you have a large collections of pixels or do a lot of animations, make sure to use the NEO_SYNC flag; this will wait until the current Dma send is done before updating the DMA buffer from the working buffer. Sort of like VSYNC with computer monitor graphics.
Jan 14 2016 20:28
Cools beans! Thanks.
I'll give it a go when I can connect gpio3 won't be till march though. Also won't get my esp31b till then either!!