PDT-11/xxx The PDT series are essentialy the same, a 8085 to handle serial IO plus a biderectional 8bit parallel port to either nothing (/110), a parallel IO varient of the TU58 (/130) or a board with another 8085 and 1771 FDC to run two 8" RX01 compatable floppies (/150). The chipset is KD11 (same as LSI-11 and 11/2) sans KEV11 FIS. Runs RT11 and maybe other stuff. Programming the IO is a bit more sane that PRO and some ports emulate DL interface and lines but, it's still not standard unibus or Qbus 11. Allison