Date   : Sat, 21 Sep 2002 11:33:32 +0200
From   : John Kortink <kortink@...>
Subject: Re: BBC B with edge-connectors instead of IDC connectors?

On Sat, 21 Sep 2002 09:43:16 +0100, Tim Fardell wrote:

>[...]
>
>Anyway, I have just found (at the local rubbish tip) a BBC model B: 
>
>[...]
>
>I have a couple of questions about it, and I wondered if anyone could
>shed any light? 
>
>a) The User Port, 1MHz Bus and Tube connectors appear to be card-edge
>connectors instead of the usual IDC connectors - is this common? 

They aren't. They're just not fitted. Must be an upgraded
model B where they 'forgot' to fit the three connectors.

>There also appears to be no Analogue port on the back

One more sign of having been a model A.

>b) There is a ROM labelled "DNFS" (can be seen in the pic above). What's
>this? 

DFS + NFS + Tube I/O code. Usually only fitted to machines
that (have) run a 6502 second processor.

>Any info would be appreciated. 
>
>Oh, one other thing - can I safely swap the ADFS ROM out of my Master
>into the B? I assume I will need this if I want to use the disk drive on
>the B? 

Probably not possible. The Master is largely backwards compatible
with the beeb but it looks like you have a 8271 controller, not
the 1770 that the Master uses. I don't think ADFS on a Master
supports the 8271.


John Kortink