no chars on uVAX console

From: allisonp <allisonp_at_world.std.com>
Date: Sat Apr 8 15:05:35 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
Received on Sat Apr 08 2000 - 15:05:35 BST