PIO code for 8-bit parallel

[troisiemetype]

Hello,

Currently rebooting a project started on the ESP32 to make profit of the PIO, I spent the major part of yesterday playing with PIO and understanding exactly what your PIO code do, and what functions are calling it at which precises steps.

That brings me to two things :

• Would it be possible to share in the library the asm code you wrote ? I believe it could make it easy to understand what's going on with the human-readable labels, and maybe your comments ?
• I'm not sure to understand exactly what the out pins, 24 lines do : I first supposed they drop unwanted values, but in both case they are used, as they are followed by a clock edge.
  So, as I understand it : bits 8-31 are output to pins (OSR is read from the left), with only bits 8-15 being effectively taken into account, bits 16-31 being out of PIO output mask.
  Then the remaining 8 bits are output.
  And the reason for that is that display controllers want MSB first data. That configuration makes it difficult to use the autopull and pull threshold that are built into the PIO. 16 bits would imply shifting the OSR to the right, but then the data would be sent LSB first.
  Is that it, or am I missing something ?