.\" $OpenBSD: adb.4,v 1.18 2007/05/31 19:19:55 jmc Exp $
.\"
.\" Copyright (c) 2001 Peter Philipp
.\" Copyright (c) 1997 Colin Wood
.\" All rights reserved.
.\"
.\" Redistribution and use in source and binary forms, with or without
.\" modification, are permitted provided that the following conditions
.\" are met:
.\" 1. Redistributions of source code must retain the above copyright
.\"    notice, this list of conditions and the following disclaimer.
.\" 2. Redistributions in binary form must reproduce the above copyright
.\"    notice, this list of conditions and the following disclaimer in the
.\"    documentation and/or other materials provided with the distribution.
.\" 3. All advertising materials mentioning features or use of this software
.\"    must display the following acknowledgement:
.\"      This product includes software developed by Colin Wood
.\"      for the NetBSD Project.
.\" 4. The name of the author may not be used to endorse or promote products
.\"    derived from this software without specific prior written permission
.\"
.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
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.\" NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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.\"
.Dd $Mdocdate: May 31 2007 $
.Dt ADB 4 macppc
.Os
.Sh NAME
.Nm adb
.Nd introduction to Apple Desktop Bus support
.Sh SYNOPSIS
.Cd "adb0 at macobio?"
.Cd "abtn* at adb?"
.Cd "akbd* at adb?"
.Cd "ams* at adb?"
.Cd "apm0 at adb?"
.Cd "piic0 at adb?"
.Sh DESCRIPTION
The Apple Desktop Bus
.Pq Tn ADB
is the single-master, multiple-slave, low-speed serial bus
interface used by Macintosh computers to connect input devices
such as keyboards, mice, trackballs, and graphics tablets
to the machine.
.Pp
Originally developed for the Mac68K port, the
.Nm
driver was heavily modified when it was ported to the PowerPC architecture.
During this port it seems that the original
.Nm
event device was split into many smaller subsystems, namely:
.Pp
.Bl -enum -compact
.It
Apple Keyboard driver
.Pq Xr akbd 4 .
.It
Apple Mouse Support driver
.Pq Xr ams 4 .
.El
.Pp
New
.Nm
devices such as the Apple Brightness / Volume Control Button
.Pq Xr abtn 4 ,
some energy control
.Pq Xr apm 4 ,
and I2C controller
.Pq Xr piic 4
were added to the PowerPC port later to complement the ADB system.
.Pp
.Ox
provides support for the following devices:
.Pp
.Bl -tag -width "abtn(4)XX" -offset 3n -compact
.It Xr abtn 4
Apple brightness/volume button control
.It Xr akbd 4
Apple Keyboard Device
.It Xr ams 4
Apple Mouse Support
.It Xr apm 4
advanced power management device interface
.It Xr piic 4
Apple via-pmu I2C controller
.El
.Sh SEE ALSO
.Xr intro 4
.Sh HISTORY
The
.Nm
interface first appeared in
.Nx 0.9 .
It has been under development ever since.
The original
.Nm adb
manpage was written by Colin Wood for
.Nx Ns / Ns Mac68K.
.Sh AUTHORS
Original ADB support was written by Bradley A. Grantham.
The direct ADB routines were written by John P. Wittkoski.