Led matrix 64x64 1/32s HUB75 with only A, B and NC lines
See https://github.com/hzeller/rpi-rgb-led-matrix/issues/120

Apparently there is concern that github might fall off the face of the earth, so hopefully this intro can pass muster...  There is a lot more detail in that linked thread than I can summarize adequately, but I think these are the important bits:


  do you think that the pannel may be driven this way :
  
  Display bottom line (32th) send 1 line of data (RGB+Clock) x64, strobe
  A, up B, strobe A x31, down B strobe latch Display previous line up B,
  strobe A, down B send 1 line of data (RGB+Clock) x64, strobe A, up B,
  strobe A x30, down B ... and scan all 32 lines ?


and


  I think the roles of pins : A : strobing pushes display one row down.
  B : down, pushed row (by A strobe) is lit, down pushed row is black.
  Clocking data set it on all rows. So for each scan, I clock the data,
  and push only one lit row (with A and B). So I push down first row as
  lit, and the remainings as black, so the "lit" row moves down.


There are code samples in there for driving a panel with an RPi.  Timing is apparently also important but it's possible that I'm misreading exactly how, and I have not had time to really study it.  I'm working on an FPGA panel driver but back-burnering implementing this feature for now.