X-Received: by 10.140.100.197 with SMTP id s63mr1059065qge.4.1457468921154; Tue, 08 Mar 2016 12:28:41 -0800 (PST) X-Received: by 10.140.43.245 with SMTP id e108mr513653qga.5.1457468921107; Tue, 08 Mar 2016 12:28:41 -0800 (PST) Path: csiph.com!usenet.blueworldhosting.com!feeder01.blueworldhosting.com!peer02.iad.highwinds-media.com!news.highwinds-media.com!feed-me.highwinds-media.com!y89no6304162qge.0!news-out.google.com!h70ni303qge.0!nntp.google.com!y89no6304158qge.0!postnews.google.com!glegroupsg2000goo.googlegroups.com!not-for-mail Newsgroups: comp.sys.3b1 Date: Tue, 8 Mar 2016 12:28:40 -0800 (PST) In-Reply-To: Complaints-To: groups-abuse@google.com Injection-Info: glegroupsg2000goo.googlegroups.com; posting-host=140.177.205.223; posting-account=LHPPOAoAAACH2HtQb3N4TyHinqnhI0BV NNTP-Posting-Host: 140.177.205.223 References: <11f11849-2c2c-433a-ad2f-555403129d14@googlegroups.com> <3d6fddd8-7124-4cd5-8c92-b0c30fefa122@googlegroups.com> User-Agent: G2/1.0 MIME-Version: 1.0 Message-ID: <063e5509-b1d1-46cd-bd3e-96b93d20964e@googlegroups.com> Subject: Re: I could use a hand locating hardware bits and pieces and/or technical documentation for repair. From: Chris Smith Injection-Date: Tue, 08 Mar 2016 20:28:41 +0000 Content-Type: text/plain; charset=ISO-8859-1 X-Received-Bytes: 4320 X-Received-Body-CRC: 1294102696 Xref: csiph.com comp.sys.3b1:443 On Sunday, March 6, 2016 at 10:25:12 PM UTC-6, DoN. Nichols wrote: > > I'll poke around a bit at it next week hopefully. This is true of the > > Unix PC keyboard. I can't plug the other one in since I don't currently > > have the computer for it. :) > O.K. I've gone to _The Reference Manual_, and found that the > serial chip for the keyboard is on sheet 14 of the system board > schematics. It gives the following pin functions: > > KBDTXD --> JK-7 > GROUND --> JK-1,2,3 > +5V --> JK-4,8 > KBDRST --> JK-5 > KBDRD <-- JK-6 > Chassis Ground to JK-shield > > with "JK" being the jack on the system board into which the keyboard > plugs. Thanks. It's good to have this from a somewhat authoritative source, and it agrees with what I've found so far. > At a guess it is something like this: > > 5 6 7 8 > : : : : > 1 2 3 4 > > Making the GROUNDs a row along one side (bottom as I show it here, but > check which three are shorts together -- perhaps examine the underside > of the keyboard PC board under the connectors) and the +5V is the two > together at the end past the GROUND pins. That would make the KBDRST > the one adjacent to the first ground pin, the KBDRD the middle of the > three, and the KBDTXD adjacent to one of the +5V pins. Not looking at it just now, but yes it's something very much like that. The grounds are a row and the +5v lines are a column on one side, leaving RST and the tx/rx pair in one corner of the connector. > > That's the plan. I believe the connector is something called sdl. > > The old pc keyboard used a six pin connector to hook the cable up to the > > keyboard. This one uses an 8 pin one. It's something like a modular > > plug with contact edges along the top, but also a shielded shell. It's > > flatter and wider than an RJ, with catches on the sides instead of on > > the bottom. I'm not absolutely sure of this but I can order a couple of > > the connectors and try it. Not yet sure how I'll get them crimped on to > > a cable, though. I don't have the original cable that went to the > > computer, but in pictures they look D-shaped on the system end. > > So -- this is a female connector on the keyboard itself, instead > of on a cable. Unfortunately so. :) > I'm thinking that the transmit bursts are short enough (high > baud rate) so the chances of a collision with the mouse signals is > minimal. Perhaps the mouse signal is sent through a gate which is > turned off when the keyboard is about to transmit a keystroke. (Likely > turned off just long enough before so a mouse signal could complete or > time out before the keyboard character or characters were sent.) > > Anyway -- you should expect the keyboard end of the 3B1 cable to > be the same as the computer end -- no crossing of pins between the ends. Previous experiments also show this to be the case. Chris