So I stumbled on this repo containing logic analyzer software that uses the Pico as hardware and provides a firmware for it.
Maybe it’s something for bp5?
It is a good one, I agree 
There is a port of the project in the forum for BP5.
The integrated logic analyzer in BP5 is also based on the PIO programs in the project. I would have copied it completely, but it is GPL licensed (we’re MIT license) and it was a good experience learning how the PIO works.