Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!tut.cis.ohio-state.edu!ucbvax!agate!web-2b.berkeley.edu!c60a-1fy
From: c60a-1fy@web-2b.berkeley.edu (Anon)
Newsgroups: comp.sys.amiga.tech
Subject: Re: Lucas Board
Summary: Generic expansion device fix
Keywords: LUCAS CLtd
Message-ID: <19949@agate.BERKELEY.EDU>
Date: 4 Feb 89 21:12:51 GMT
References: <650@csd4.milw.wisc.edu> <166@ziggy.UUCP> <19943@agate.BERKELEY.EDU>
Sender: usenet@agate.BERKELEY.EDU
Distribution: comp.sys.amiga.tech
Lines: 29

On my last message, I swapped the two chips used as U9.  I have a 7474
connected to pins 1-6 and a 74ALS74 connected to pins 8-14.  It has now
been running 6 hours with 0 (zero!) crashes!!!

I never did like the idea of trying to find "the right" U9 to satisfy
both gates.  Sure, you might be able to do it with an empty amiga, but 
when you start stacking on them expansion devices, Lucas gets real
unhappy.  If you're lucky, you might get something that works, but it
might me flakier than if you separated the gates.

My guess is that spitting the gates in U9 and possibly terminating
the bus if you have a starboard should get any system to work, since that
is really the only "flaw" in the lucas board.

I make the piggyback assy with 3 14 pin sockets as follows.  It's pretty
neat, although it will guarantee that you'll never get that emission shield
back on (awww... gee, big loss).



              //- -\\    <- Two sockets w/ one edge in base socket
             //     \\
              =======    <- Socket plugging into U9 socket
	      |     |

Then, just add two stiff wires so both chips are connected to 7 and 14 (pwr),
and also to keep the unconnected edges of the side sockets from touching.

-Vince Lee