Date   : Tue, 27 Nov 2001 13:47:52 -0500 (EST)
From   : Victor Rozanov <vic792r@...>
Subject: Help needed.

Hi,

Sorry for asking that stupid question again.
But I spent last weekend in trying to make the B+/128
to work as B and had no luck at all:(
I need this because there are a lot of games around which refuse
to work on B+. The last one I tried was Dunjunz.
It works fine with the emulator (BeebEM)in B mode and the
Master mode with the various OSROMs BASICs and DFSes but
unfortunately it  does not work on  my real B+/128.
I used my oscilloscope to look at the IC36 (PAL) signals
especially VDUSEL and CPUSEL and found out that there is
some activity when you start the games which crash the Beeb.
( I tryed OS 2.0 and 1.20 roms with the same results ) that was
basicaly what pointed me to that IC36. It controls all paged
and shadow memory and all ROM banks. I even tryed to cut
and ground VDUSEL/CPUSEL still with no luck.
I am trying to find the way to make a switch
BBC B / B+.  I found the schematic for that kind of switch for
the Master but there is nothing like this for B+
Can anybody point me to the right direction?

Thank you in advance.
Best regards.

Victor.