From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from 12-225-100-78.client.attbi.com (12-225-100-78.client.attbi.com [12.225.100.78]) by dsl2.external.hp.com (Postfix) with ESMTP id 1B5DA482A for ; Sat, 9 Feb 2002 10:50:05 -0700 (MST) Date: Sat, 9 Feb 2002 09:53:36 -0800 From: collver@linuxfreemail.com To: lug@peak.org Cc: Allen Brown , parisc-linux@lists.parisc-linux.org Message-ID: <20020209095335.A4426@glen.takilma.net> References: <200201150347.g0F3lh129546@tpol.peak.org> <20020204104006.A6794@glen.takilma.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <20020204104006.A6794@glen.takilma.net>; from collver@linuxfreemail.com on Mon, Feb 04, 2002 at 10:40:07AM -0800 Subject: [parisc-linux] Re: serial breakout box Sender: parisc-linux-admin@lists.parisc-linux.org Errors-To: parisc-linux-admin@lists.parisc-linux.org List-Help: List-Post: List-Subscribe: , List-Id: parisc-linux developers list List-Unsubscribe: , List-Archive: On Mon, Feb 04, 2002 at 10:40:07AM -0800, collver@linuxfreemail.com wrote: > >>This is an Apollo 400 which has been upgraded to a 715T/50 (Trailways-50). > > > > Pin 7 is GND. Pins 2 and 3 are the input and outputs, not necessarily > > in that order. Measure from 7 to 2. Measure from 7 to 3. One > > of them will be close to 0V. The other will be much higher. I think > > -10V or something like that. The pin with the higher voltage is > > the output. > > > > Do the same thing on the other system also using the 25 pin connector. > > Then make sure you are not connecting the output to the output. > > It turns out the Apollo 400 has a funky serial pinout. > I obtained a breakout box and when I find the time, I will experiment with > this strange serial port. The Apollo 400 and the mouse are both "DCE". I can measure -11.44V on the Apollo's pin 2 and on the PC's pin 3. I have verified that the mouse will speak to my PC using only txd, rxd, and rts. I can also log into the Apollo from the PC using only txd, rxd, and rts. It is obvious the I need to connect the mouse's pins 2 and 3, to the Apollo's pins 3 and 2. The rest is unsure. I have tried many combinations of wiring, and I just haven't been able to get the mouse to work. To connect two DCE devices, some suggest a "tail circuit cable". It seems overkill to me since the mouse only uses a few pins. I have noticed that the Apollo doesn't ever show voltage on the "carrier detect" pin. I have also noticed that the Apollo voltage is -11.44 volts, and the PC voltage is -12.15 volts. Can anyone give me tips for getting this mouse to work? Thanks, Ben