NetBSD/share/man/man4/pcppi.4

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.\" $NetBSD: pcppi.4,v 1.3 2001/01/28 01:39:41 nathanw Exp $
.Dd April 21, 1999
.Os
.Dt PCPPI 4
.Sh NAME
.Nm pcppi
.Nd PC (ISA) control and timer port driver
.Sh SYNOPSIS
.Cd pcppi* at isa?
.Cd isabeep* at pcppi?
(alpha only)
.Cd sysbeep* at pcppi?
(i386 only)
.Sh DESCRIPTION
The
.Nm
driver handles resource allocation and device attachment for the
ports related to the ISA speaker in the traditional PC/AT
.Dq design .
These are the
.Dq system control port
(which was implemented by the 8255
.Dq PPI
in the XT, hence the name of this driver)
at IO address 0x61 and the first 8253 timer at 0x40-0x43.
.Pp
The
.Nm
driver provides its child devices with the ability to output simple
tones through the PC speaker. The
.Xr speaker 4
and
.Xr midi 4
devices use this to synthesize sounds.
The
.Xr isabeep 4
and
.Xr sysbeep 4
devices are helpers which the
.Xr pckbd 4
driver uses as a substitute for a
.Dq keyboard beep ,
because the PC keyboard hardware doesn't provide this.
.Sh SEE ALSO
.Xr isa 4 ,
.Xr speaker 4 ,
.Xr midi 4 ,
.Xr pckbd 4