If you look in the vax kernel subtree on 4.4BSD-Lite you should find most of
the drivers there (but I don't have any detailed info on the 5400 w.r.t what
devices it has).

uda.c - mscp disk interface (UDA50, RQDX2/3, KDA50 and clones) with
	unibus/qbus port interface
tmscp.c - tape mscp interface (TK50 etc.)
if_qe.c - DEQNA ethernet

I don't think the dhu.c (DHV11) driver made it, since it still has vestiges
of old 32V dz.c code in it. There were also drivers for the qvss and qdss
display interfaces.
(The *real story* on the MicroVAX II port was that I did it for 4.2 and then
 offered it to BSD. Mt. Xinu (mostly Dave Slatengren (sp?)) offered to help
 Berkeley inegrate it in return for early access to the code. Mt Xinu also
 donated the instruction emulation code that they did. After this was done,
 DEC agreed to donate the Ultrix drivers for tape mscp and DEQNA, since they
 actually functioned correctly do to the fact that the DEQNA didn't conform
 to its own programming spec. To give you a clue how long ago this was,
 Mt. Xinu actually grabbed the code off of a machine here via. 1200bps modem
 using kermit:-)

Anyhow, if you can get the tech info on the 5400, it shouldn't be too much
work to get going.
Have fun, rick

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