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Markup fixes.

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This commit is contained in:
Ruslan Ermilov 2005-01-14 09:40:13 +00:00
parent 5b90d0e8d2
commit 8de5fd36d9
1 changed files with 16 additions and 10 deletions
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26
share/man/man4/man4.i386/pbio.4
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@ -35,11 +35,17 @@
.Tn I/O
driver
.Sh SYNOPSIS
.Cd "device pbio0 at isa? port 0x360"
.Cd "device pbio"
.Pp
In
.Pa /boot/device.hints :
.Cd hint.pbio.0.at="isa"
.Cd hint.pbio.0.port="0x360"
.Pp
.In machine/pbioio.h
.Sh DESCRIPTION
The
.Xr pbio 4
.Nm
driver supports direct access to the Intel 8255A programmable
peripheral interface (PPI) chip running in mode 0 (simple
.Tn I/O ) .
@ -77,7 +83,7 @@ The device driver provides four character devices that
correspond to the peripheral's
.Tn I/O
ports.
Opening a device for read or write, automatically configures
Opening a device for read or write automatically configures
the corresponding hardware port for input or output.
At boot time all ports are set configured for input to avoid damaging
external circuitry.
@ -90,7 +96,7 @@ user/kernel context switching.
The driver can perform
.Tn I/O
in three different ways:
.Bl -tag -width Differential
.Bl -tag -width ".No Differential"
.It Basic
The read or write operation returns immediately after reading
or writing the data to the port at bus speed.
@ -108,19 +114,19 @@ The pacing interval is specified in
.Em Hz
unit increments.
Setting a pace of
.Sy n
.Ar n
seconds
will result in no more than one value being read or written every
.Sy n
.Ar n
seconds.
Single byte read/write opeations will take at least
.Sy n
.Ar n
seconds to complete.
.Pp
The following
.Xr ioctl 2
calls are supported:
.Bl -tag -width "PBIO_SETIPACE"
.Bl -tag -width ".Dv PBIO_SETIPACE"
.It Dv PBIO_SETDIFF
accepts a pointer to an integer as the third argument,
and sets the driver for differential input if the integer is non-zero.
@ -143,7 +149,7 @@ accepts a pointer to an integer as the third argument,
and sets the integer to the last set value for the output pace.
.El
.Sh FILES
.Bl -tag -width "/dev/pbioxxx"
.Bl -tag -width ".Pa /dev/pbio0ch" -compact
.It Pa /dev/pbio0a
Port A (8 bit
.Tn I/O ) .
@ -172,7 +178,7 @@ The
.Nm
device was first used under
.Fx 4.1 .
.Sh AUTHOR
.Sh AUTHORS
.An "Diomidis D. Spinellis" Aq dds@aueb.gr
.Sh BUGS
One of the