"sokolov@alpha.CES.CWRU.Edu" "Michael Sokolov"

>still different in that the MicroVAX version had the video circuitry
>omitted. Well, among the stuff that Richard Parobek has given me on
>Thursday there are two MV2000s. To test my theory, I have opened them up
>and looked at the system boards. I was expecting to see signs of omitted

I no longer have my original post so I don't know whether I said or not, but the 
MicroVAX 2000 and the VAXstation 2000 are the same board. To convert from one or 
the other you move one jumper and add or remove the external converter unit that 
gives you MMJs instead of a video output.

I believe the console scribbles KA410-A or KA410-B depending on the position of 
the jumper, but I cannot verify that right now (since my MicroVAX 2000 is a tad 
sick).

>Everything works out nicely. On VS3100, on the other hand, something
>strange is going on. Ports 2 and 3 come out of the system unit already as
>MMJs, and ports 0 and 1 come out in two ways. First, they are accessible
>through the monitor DB15, but there also are funny keyboard and mouse
>connectors right on the system unit. On MV3100 all ports should be MMJs,
>but I don't see how could they do it. My question to the club is this:

They do it because the circuit boards are not the same!

>could someone with an MV3100 M10/10e/20/20e (but not M30+) please look at
>its back panel and tell me what connectors does it (left to right or right
>to left, doesn't matter)? I remember someone saying that he has such a box.

Viewed from behind and not to scale :

VAXstation 3100:
   AUI ThinWire KB Mouse Video MMJ* MMJ Switch

MicroVAX 3100 Model 10
   AUI ThinWire MMJ MMJ MMJ* DB-25 Switch

In each case MMJ* denotes the connection used as the alternate console.

The layout changed with the MicroVAX 3100-30 upwards.

Antonio

Antonio Carlini                            Mail: carlini@marvin.enet.dec.com
DECnet-Plus for OpenVMS Engineering
Digital Equipment Corporation              Worton Grange, Reading, England