Date   : Thu, 28 Oct 2010 16:10:21 +0200
From   : kortink@... (John Kortink)
Subject: Reversing the Tube ULA (destructively)

On Thu, 28 Oct 2010 15:00:00 +0100, Ed Spittles
<percy.p.person@...> wrote:

>On 28 October 2010 13:34, J.G.Harston <jgh@...> wrote:
>
>> Theo Markettos wrote:
>> > There are imaging and etching techiques to strip off the layers one by
>> one,
>> > but they require a lot of trial and error... and there aren't plenty of
>> > samples to test on.
>>
>> Chris Smith has successfully done this with the Spectrum ULA:
>> http://www.zxdesign.info/book - It's a fascinating read. He
>> used up three or four ICs to get the full image.
>
>
>I hope we'll only need one Tube ULA, but this is the reason I'd like to use
>a broken one - they are in short enough supply as it is.

Not a good idea. The reason why a ULA 'broke' may well
be something that smoked the die to a crisp as well
(or at least part of it).

>I did find some good ULA info in that book (is there perhaps a sample
>chapter online? I know I haven't bought it)

Just a few pages.

The actual book contains a 30+ page story about Ferranti
ULAs, which makes it interesting for Acorn aficionados
as well (well, I've yet to read it, but it looks that
way).


John Kortink

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