Return-Path: Received: from cloud9-2.dh.bytemark.co.uk (cloud9-2.dh.bytemark.co.uk [89.16.179.42]) by mxdrop103.xs4all.nl (8.13.8/8.13.8) with ESMTP id pBEN7bsu078876 for ; Thu, 15 Dec 2011 00:07:38 +0100 (CET) (envelope-from bbc-micro-bounces+eelco=huininga.nl@lists.cloud9.co.uk) Received: (qmail 14121 invoked from network); 14 Dec 2011 23:07:31 -0000 Received: from unknown (HELO cloud9-2.dh) (127.0.0.1) by cloud9-2.dh.bytemark.co.uk with SMTP; 14 Dec 2011 23:07:31 -0000 Received: from loc6.paulbunyan.net ([209.191.199.141] helo=smtp.paulbunyan.net) by cloud9-2.cloud9.co.uk with esmtp (Exim 4.72) (envelope-from ) id 1Raxv5-0003cL-Qf for bbc-micro@lists.cloud9.co.uk; Wed, 14 Dec 2011 23:07:28 +0000 Received: from [192.168.2.101] ([172.28.160.93]) by smtp.paulbunyan.net (8.14.3/8.13.6) with ESMTP id pBEN7PEQ024798 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO) for ; Wed, 14 Dec 2011 17:07:25 -0600 Message-ID: <4EE92C1F.1090504@gmail.com> Date: Wed, 14 Dec 2011 17:07:11 -0600 From: Jules Richardson User-Agent: Thunderbird 2.0.0.23 (X11/20090812) MIME-Version: 1.0 To: bbc-micro List References: <4CD29F80.1030401@gfarlie.demon.co.uk> <4CD2D139.2020707@gmail.com> <20101104155707.sozi2hx40kscskc4@webmail.mdfs.net> <20101104155852.i95wpaq7gkgsg884@webmail.mdfs.net> <4CD2DFB8.4080203@gmail.com> <4CD3597F.7060508@rs432.net><4CD3F6E3.5010801@gmail.com><000601cb7ce8$33862f80$9a928e80$@demon.co.uk> <49h9e7psgh44iecn40nrep2aukltsu82h4@4ax.com> <002301ccb849$19891780$de00a8c0@desk> <4EE6A150.7010608@gmail.com> In-Reply-To: <4EE6A150.7010608@gmail.com> Subject: Re: [BBC-Micro] 32016 + 32082 X-BeenThere: bbc-micro@lists.cloud9.co.uk X-Mailman-Version: 2.1.9 Precedence: list List-Id: BBC Micro & related machines List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: bbc-micro-bounces+eelco=huininga.nl@lists.cloud9.co.uk Errors-To: bbc-micro-bounces+eelco=huininga.nl@lists.cloud9.co.uk X-XS4ALL-DNSBL-Checked: mxdrop103.xs4all.nl checked 89.16.179.42 against DNS blacklists X-CNFS-Analysis: v=1.1 cv=0zc6fmG9YcuPB4Yp6G+9JUp7sX0X0uIJmZE+jPYAbEE= c=1 sm=0 a=dUrd-BE2TjcA:10 a=nDghuxUhq_wA:10 a=BLceEmwcHowA:10 a=kj9zAlcOel0A:10 a=bE7SG8RJruwtBMhJEyeceg==:17 a=T4_NvvuVAAAA:8 a=thFPR7iZ04IlsWmn8WYA:9 a=TqSrmoGehor_bvnLqJAA:7 a=CjuIK1q_8ugA:10 a=U4BfqbWQEiHEEz78:21 a=FAouxo3C5J9aHB9U:21 a=bE7SG8RJruwtBMhJEyeceg==:117 X-Virus-Scanned: by XS4ALL Virus Scanner X-XS4ALL-Spam-Score: 0.0 () none X-XS4ALL-Spam: NO Envelope-To: eelco@huininga.nl Jules Richardson wrote: > None of my boards have IC16 fitted (just like yours). > > However, none of my boards have a socket fitted for IC6, unlike yours - > which might suggest that yours once had something fitted there that has > gone AWOL. I don't know if that IC is related to MMU functionality, however. I manage to track down someone with a schematic for the 1MB board, so just as a FYI: IC6 is supposedly a TBP24S10 - a 256x4 PROM. It's purpose was to correct timing on the IRQ and NMI lines, and if it's fitted then LK8 and LK9 are supposed to be cut. It's marked as NF on the schematic. The schematic's owner thinks that it was only needed to correct a timing flaw in an early version of one of the copro's chips, and that a similar issue existed on the 4MB board and is mentioned in the ACW service manual. Quite why your board (which seems to use quite late parts) has a socket fitted, I don't know. IC16 is a 74LS365, and is fitted to access the unused 6 links in the LK5 block. Again, marked as NF on the schematic. cheers Jules _______________________________________________ bbc-micro mailing list bbc-micro@lists.cloud9.co.uk http://lists.cloud9.co.uk/mailman/listinfo/bbc-micro