Maximizing frame rate on a large-ish matrix

So I want to do a 32x32 matrix of bullet pixels. This started as a tangent from working on a smartmatrix build that played animated gifs on a hub75 panel, so the original goal was “make a giant one of those!”

I was bringing it up in stages and when I got to 256 pixels, it felt less buttery smooth than 128 so I’m looking at 8 inputs it seems.

Is that doable on a pixelblaze without the output expander? I have one but wanted to save that for the house Christmas lights.

Especially if your LEDs are WS2812 or similar, I’d highly recommend using the output expander. Given the WS2812 protocol’s 800Khz communications speed, the maximum frame rate you can get from 1024 driven via a single output is around 30fps.

Using 8 channels of the output expander to drive 128 LEDs each, my Pixelblaze 3 running the “New Pattern” pattern runs at (very slightly) better than 60fps.

The final speed of your display will depend tremendously on how much per-pixel calculation you do in pattern code. But for a 32x32 matrix, using the expansion board ensures that communication with the LEDs is not going to be your bottleneck.

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Ok cool. I converted the expander to 5v and it looks good. Thanks!