FastLED may be able to do another parallel output, simultaneously while OctoWS2811 is sending. Maybe. I have not used this, but I’ve been told it’s possible. But that sort of thing is done with busy looping code, which costs you CPU time you’d need to get the next frame rendered. I’m not a fan of quoting large numbers that have terrible caveats for any real project… even in a context like this of a hypothetical project that the author has said he don’t expect to actually build.
The 1365 per pin limit comes from the DMA engine. The way it’s used can only schedule a transfer with at most 32768 operations. Each bit is 1 DMA operation, and each LED requires 24 bits for RGB color. So 24 * 1356 = 32760, which is the largest that fits within the 32K DMA hardware limit.
@PaulStoffregen Thanks for the detailed answer. I built an 8x8x8 cube using the Teensy3.2 and the OCTOWS2811 and with only 64 leds per pin on the OCTO, I can update the whole cube about 500 times a second though it is a bit silly considering the +/- 400 hz PWM brightness control limitation. I was considering going for a 16X16X16 cube next and hoping that I could get more parallel pins out of the Teensy 3.6. Any chances of getting to an hexaWS2811 at some point ??
@JP_Roy I’ve been using PORTB (x8) and PORTDC (x16) plus another 17 pins for a total of 1220 leds on 41 pins on the 3.6. show() time is 18.3ms (54fps). It’s not exactly parallel output x24, but x8 + x16 is very performant. Plenty of processing power left for complex overlaid animations and FFT sound processing. Very impressive board.
@Franck_Marcotte 1220 LEDs without any parallel output gives about 36.6 ms update time. You should do significantly better just using 8 pins and the OCTOWS2811 library !
@Franck_Marcotte 41 is getting closer. But mega is still winning.
@Franck_Marcotte on second read that’s a pretty decent compromise to half your show time with half your leds doing parallel out. Are you using the teensy audio library and having no problems with this combination? I know all of my attempts to get a significant amount of leds to work with the library. Created issues. If your using fastled no interrupt option do you get audio glitches? Or if your allowing interrupts do you get led glitches?
Is it possible to use another 9 outputs for leds in your current setup?
Thanks.
For audio processing together with WS2812, you really need non-blocking output.
Hi @PaulStoffregen By “non blocking output” are you saying audio library with octows2811 library alone?
Will audio library with fastled/octows2811 controller also work.
Will audio library using audio adapter hardware (sg… whatever it is chip/library features) work with octows2811 library?
Thanks
@JP_Roy For that particular project I’m working with a starfish configuration so I can’t hook up all the leds on only 8 lines. I need 41 swappable lines.
As for audio, I do stop sampling while show() is running. The loss isn’t really perceptible though, for my needs.