Date   : Tue, 29 Jan 2013 00:26:04 +0000
From   : pete@... (Pete Turnbull)
Subject: Fried Ferranties; was Commodore 64 BBC BASIC

On 29/01/2013 00:02, Daniel Beardsmore wrote:
> On 28/01/2013 08:34, Rob wrote:
>> On 28 January 2013 01:57, Daniel Beardsmore <public@...>
>> wrote:
>>> Talking about crap displays -- if you use a VTI video chip on a
>>> board that had a fried Ferranti video chip (i.e. most of them ;-)
>>> and connect the machine to a TV, you get a really messed up mode
>>> 7, or at least I did. But not on a monitor. But maybe that was
>>> just a specific issue with that computer. But that's getting way
>>> off topic now :)
>> 
>> That's a known issue, due to a difference between the chips.
>> There's a mod-wire that needs adding or removing, depending on
>> which way you are going.  Don't forget the heatsink, too :-)

Not exactly, that's only an issue with the first issue of the VTi video
processor (type 2023): remove Link 26, which is the normal/inverse link;
fit a wire under the PCB from IC6 pin 27 (or S26 centre pin) to IC10 pin
1.  The more common later ones (type 2069) use the link like the ULA and
shouldn't have the wire.

-- 
Pete                                           Peter Turnbull
                                               Network Manager
                                               University of York