Date : Wed, 17 May 2006 12:21:02 +0100
From : "David Harper" <dl.harper@...>
Subject: Re: Any ideas?
M J Forbes wrote:
Found this in a box of Beeb bits the other day ...
http://www.freewebs.com/mjforbes/romthing.jpg
http://www.freewebs.com/mjforbes/romthing2.jpg
Anyone got any idea what it is? The lettering on the chip on the
underside is PC74HCT - D4T if that's any help!
It's definitely a 16kb SW-RAM bank. I had one exactly like this on my
Model B, though I do not remember who supplied it. (It may have been
Acorn User.)
The flying lead clips to one of the legs of the CPU. I cannot remember
which leg, though I do remember it is not the one you would expect -
i.e. it is not the R/W line. I have a feeling it was a memory strobe.
David Harper
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<DIV><FONT face=Arial size=2>M J Forbes wrote:</FONT></DIV>
<BLOCKQUOTE dir=ltr
style="PADDING-RIGHT: 0px; PADDING-LEFT: 5px; MARGIN-LEFT: 5px;
BORDER-LEFT: #000000 2px solid; MARGIN-RIGHT: 0px">
<DIV><SPAN class=234245906-17052006><FONT face=Arial
size=2>Found this in a
box of Beeb bits the other day ...</FONT></SPAN></DIV>
<DIV><SPAN class=234245906-17052006><FONT face=Arial size=2><A
href="http://www.freeweb">http://www.freewebs.com/mjforbes/romthing.jpg">http://www.freeweb
s.com/mjforbes/romthing.jpg</A></FONT></SPAN></DIV>
<DIV><SPAN class=234245906-17052006><FONT face=Arial size=2><A
href="http://www.freewe">http://www.freewebs.com/mjforbes/romthing2.jpg">http://www.freewe
bs.com/mjforbes/romthing2.jpg</A> </FONT></SPAN></DIV>
<DIV><SPAN class=234245906-17052006><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=234245906-17052006><FONT face=Arial
size=2>Anyone got any
idea what it is? The lettering on the chip on the underside is
PC74HCT -
D4T if that's any help!</FONT></SPAN></DIV></BLOCKQUOTE>
<DIV dir=ltr><SPAN class=234245906-17052006><FONT face=Arial
size=2>It's
definitely a 16kb SW-RAM bank. I had one exactly like this on my Model
B, though
I do not remember who supplied it. (It may have been Acorn
User.)</FONT></SPAN></DIV>
<DIV dir=ltr><SPAN class=234245906-17052006><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV dir=ltr><SPAN class=234245906-17052006><FONT face=Arial
size=2>The flying
lead clips to one of the legs of the CPU. I cannot remember which leg,
though I
do remember it is not the one you would expect - i.e. it is not the R/W
line. I
have a feeling it was a memory strobe.</FONT></SPAN></DIV>
<DIV dir=ltr><SPAN class=234245906-17052006><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV dir=ltr><SPAN class=234245906-17052006><FONT face=Arial
size=2>David
Harper</FONT></SPAN></DIV></BODY></HTML>