Code changes for Picade Max 128x32 Interstate 75 marquee

[elaurijssens]

• Interstate 75 code now uses hub75 instead of hub75_legacy library.
• added optional data compression for higher frame rates when displaying animated gifs
• small code fixes

It took a while to pull the zlib library into the project. The pngdec library contains some zlib code as well but not all, so I decided to get it from the source. Not sure if this is the way to go, but here we are.

[Gadgetoid]

Awesome stuff, thank you! Saw your animations in action in the Discord and they're ✨slick ✨

The zlib addition might also be very relevant to @criggs interests 👀

[elaurijssens]

You're welcome 😄

I built it locally against SDK 2.0 so I guess you can add that bump to version 2.0.0 as well.

[criggs]

Oh, I'm definitely going to look at this! Strangely, USB hubs can't handle fully saturated USB 1.1 speeds without some throughput degradation on each hub hop. Some might see that as a reason not to build a video wall with 16 dedicated rp2040 controllers running at slower than USB 1.1 speeds.... I was going to call it good enough and let it be a bit janky, now it can be a bit less janky!

[elaurijssens]

The code that writes the data to my single i75 controller is here:

https://github.com/elaurijssens/pixel-multiverse

in matrix.py at line 90 you can check out how sending compressed data works.

There's a demo here: https://youtu.be/TLCHtcdh-D8?si=r7995v4sXlCT2t_4

[Gadgetoid]

It might be worth vendoring https://github.com/bitbank2/zlib_turbo in lieu of Zlib, if it's faster/leaner in this use case. We could potentially get even more frames.

[elaurijssens]

I tried getting zlib_turbo to run but I'm running into issues where the i75 crashes for no apparent reason. I must be doing something quite wrong but there's so much to do and so little time so I've settled for zlib for now.