Subject: Re: PS/2 Mouse vs. Serial Mouse
To: None <port-i386@NetBSD.ORG>
From: Todd Vierling <tv@pobox.com>
List: port-i386
Date: 08/16/1996 10:41:16
On Thu, 15 Aug 1996, Gary D. Duzan wrote:

: =>What's the current state of the PS/2 mouse driver in current? Is
: =>it working ok these days? I take it it translates PS/2 mouse codes
: =>into Microsoft codes for the X server?
: 
:    It has been working with no problems for me for quite a while.
: And yes, the pms driver provides a bus mouse interface.

Okay, I'm confused.  How does a PS/2 mouse relate to a bus mouse?  Here's
how I've seen mice on x86 for some time. 

- M$ serial mice can attach to a serial mouse port, or a PS/2 mouse port
  if using the special mini-DIN adapter.  (Some M$ compatible mice come
  with a mini-DIN as default and a 9-pin adapter for it.)

- PS/2 mice are identical to serial M$ compatible mice excepting the
  connector.  PS/2 mice send the same codes, same bit rate, but use a
  mini-DIN (hence you can use the adapters you see in shops).  Unlike
  some M$ clone mice, PS/2 mice usually don't have a switch to send back
  Mouse Systems codes, and therefore usually only come in two, rather
  than three, button varieties.

- A PS/2 mouse port is a serial port specially designed for mouse use;
  it isn't capable of variable speed transfer, and in some cases, is
  input-only.

- Bus mice are RADICALLY different from either PS/2 or M$ mice.  They don't
  send back codes.  In fact, all they do is toggle the direct horizontal
  and vertical position and quadrature lines.  (Sounds like an Amiga, Atari
  ST, Sony NeWS, HP, or Sun mouse?  Surprise, it is--they're all identical,
  just with different connectors.)  That's why a bus card is necessary;
  there's no electronics in a bus mouse save the optoelectronics for
  detecting movement.  (So why are they so damn expensive!? :) 

=====
== Todd Vierling (Personal tv@pobox.com; Business tv@iag.net) Amiga lives! ==
== System administrator/technician, Internet Access Group, Orlando Florida ==
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