no chars on uVAX console - test-drb@ccmp.vtda.org

8 Apr 2000

->I've removed all boards save the memory boards (2*M7609)
...
 and the CPU (M7606-AA)

Now I get characters (XON/OFF = on) and the bootprocess continues
until char 3 

Xon/Xoff is DECs standard flow control, VTxxxS know how to do that.

...
 I've tried to put some of the boards back but I am
not sure if I have a
missing
board.

Het boards were arranged as follows
  slot 1     AB/CD  >slot 1 ----------------M 7606------------------
 slot 2     AB/CD  >slot 2 ----------------M 7609------------------
 slot 3     AB/CD >slot 3 ----------------M 7609------------------
 slot 4/5  AB/AB  >slot 4 -----M7516--------            (empty)
 slot 7/6  AB/AB  >slot 5 -----M7555--------   ------M7546------
 slot 8/9  AB/AB  >slot 6         (empty)              ---Dilog sq703a---

This was the smaller BA23?   if so then the slot next to the m7516 is the
bus grant break
and the slot 6 empty is a bus grant break.  Notice my margin comments.  the
odd ordering of
slots 4-9 indicate direction of bus grant for Interrupts and DMA.

...
 The uVAX used to contain a Serial concentrator or
something 

That was likely a DHV11 or DZV11, worth having.

...
 I've gathered that the first 4 slots are different
from the rest of
the BA123, those beeing true Qbus 22 slots. 

Not quite.  It's the AB/CD vs AB/AB serpentine bus grant.  The BA123
has more of the AB/CD slots than BA23.  FYI: AB are address/data
Q22 and CD or special bussed for memory or cards that only need
power.

...
  Should I rearrange the boards ? If so what do you
suggest? 

Yes.

 slot 1     AB/CD  >slot 1 ----------------M 7606------------------
 slot 2     AB/CD  >slot 2 ----------------M 7609------------------
 slot 3     AB/CD >slot 3 ----------------M 7609------------------
 slot 4/5  AB/AB  >slot 4 -----M7516--------   ------m7546------
 slot 7/6  AB/AB  >slot 5 -----M7555--------   ------sq703A------
 slot 8/9  AB/AB  >slot 6         (empty)              (empty)

Allison