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authorRodney W. Grimes <rgrimes@FreeBSD.org>1993-08-28 12:41:23 +0000
committerRodney W. Grimes <rgrimes@FreeBSD.org>1993-08-28 12:41:23 +0000
commitb9a1ef14c0e8361c32589db2291543f30b85404b (patch)
treecbb32281c1f1ac4b01f626303f1113e206c41918 /share/man
parent8373b812380e300a370aaf2342fd66188dc3c810 (diff)
downloadsrc-b9a1ef14c0e8361c32589db2291543f30b85404b.tar.gz
src-b9a1ef14c0e8361c32589db2291543f30b85404b.zip
New manual pages from NetBSD, revised for FreeBSD slightly
Notes
Notes: svn path=/head/; revision=349
Diffstat (limited to 'share/man')
-rw-r--r--share/man/man4/man4.i386/Makefile8
-rw-r--r--share/man/man4/man4.i386/com.4102
-rw-r--r--share/man/man4/man4.i386/lpa.462
-rw-r--r--share/man/man4/man4.i386/lpt.459
-rw-r--r--share/man/man4/man4.i386/npx.477
-rw-r--r--share/man/man4/man4.i386/sio.4101
-rw-r--r--share/man/man4/sio.4101
7 files changed, 508 insertions, 2 deletions
diff --git a/share/man/man4/man4.i386/Makefile b/share/man/man4/man4.i386/Makefile
index 0bec425785ef..b95ebb7d6290 100644
--- a/share/man/man4/man4.i386/Makefile
+++ b/share/man/man4/man4.i386/Makefile
@@ -1,7 +1,11 @@
# @(#)Makefile 0.1 (RWGrimes) 3/25/93
-MAN4= mem.4 spkr.4
-MLINKS= mem.4 ../mem.4 mem.4 ../kmem.4 spkr.4 ../spkr.4
+MAN4= com.4 lpa.4 lpt.4 mem.4 npx.4 sio.4 spkr.4
+
+MLINKS= com.4 ../com.4 lpa.4 ../lpa.4 lpt.4 ../lpt.4
+MLINKS+= mem.4 ../mem.4 mem.4 ../kmem.4 npx.4 ../npx.4
+MLINKS+= sio.4 ../sio.4 spkr.4 ../spkr.4
+
MANSUBDIR=/i386
.include <bsd.prog.mk>
diff --git a/share/man/man4/man4.i386/com.4 b/share/man/man4/man4.i386/com.4
new file mode 100644
index 000000000000..4e45bab8612b
--- /dev/null
+++ b/share/man/man4/man4.i386/com.4
@@ -0,0 +1,102 @@
+.\" Copyright (c) 1990, 1991 The Regents of the University of California.
+.\" All rights reserved.
+.\"
+.\" This code is derived from software contributed to Berkeley by
+.\" the Systems Programming Group of the University of Utah Computer
+.\" Science Department.
+.\" 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 the University of
+.\" California, Berkeley and its contributors.
+.\" 4. Neither the name of the University nor the names of its contributors
+.\" may be used to endorse or promote products derived from this software
+.\" without specific prior written permission.
+.\"
+.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+.\" SUCH DAMAGE.
+.\"
+.\" from: @(#)dca.4 5.2 (Berkeley) 3/27/91
+.\" from: com.4,v 1.1 1993/08/06 11:19:07 cgd Exp
+.\" $Id$
+.\"
+.Dd August 28, 1993
+.Dt COM 4 i386
+.Os FreeBSD
+.Sh NAME
+.Nm com
+.Nd
+serial communications interface
+.Sh SYNOPSIS
+.Cd "device com0 at isa? port" \&"IO_COM1\&" tty irq 4 vector comintr
+.Cd "device com1 at isa? port" \&"IO_COM2\&" tty irq 3 vector comintr
+.Cd "device com2 at isa? port" \&"IO_COM3\&" tty irq 5 vector comintr
+.Cd "device com3 at isa? port" \&"IO_COM4\&" tty irq 9 vector comintr
+.Sh DESCRIPTION
+The
+.Nm com
+driver provides support for NS8250-, NS16450-, and NS16550-based
+.Tn EIA
+.Tn RS-232C
+.Pf ( Tn CCITT
+.Tn V.28 )
+communications interfaces. The NS8250 and NS16450 have single character
+buffers, and the NS16550 has a 16 character buffer.
+.Pp
+Input and output for each line may set to one of following baud rates;
+50, 75, 110, 134.5, 150, 300, 600, 1200, 1800, 2400, 4800, 9600,
+19200, 38400, 57600, or 115200.
+.Sh FILES
+.Bl -tag -width Pa
+.It Pa /dev/tty00
+.It Pa /dev/tty01
+.El
+.Sh DIAGNOSTICS
+.Bl -diag
+.It com%d: silo overflow.
+The single-character input
+.Dq silo
+has overflowed and incoming data has been lost.
+.\".It com%d: weird interrupt: %x.
+.\"The device has generated an unexpected interrupt
+.\"with the code listed.
+.El
+.Sh SEE ALSO
+.Xr tty 4
+.Xr sio 4
+.Sh HISTORY
+The
+.Nm
+driver is derived from the
+.Nm HP9000/300
+.Nm dca
+driver and is
+.Ud
+.Sh BUGS
+Data loss is possible on busy systems with baud rates greater than 300.
+The
+.Nm com
+driver is slow, buggy, and not properly tested.
+.Pp
+The name of this driver and the constants which define the locations
+of the various seiral ports are holdovers from
+.Nm DOS .
+.Pp
+As usual, you get what you pay for; cheap NS16550 clones
+generally don't work.
diff --git a/share/man/man4/man4.i386/lpa.4 b/share/man/man4/man4.i386/lpa.4
new file mode 100644
index 000000000000..659db5549319
--- /dev/null
+++ b/share/man/man4/man4.i386/lpa.4
@@ -0,0 +1,62 @@
+.\"
+.\" Copyright (c) 1993 Christopher G. Demetriou
+.\" 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 Christopher G. Demetriou.
+.\" 3. The name of the author may not be used to endorse or promote products
+.\" derived from this software withough specific prior written permission
+.\"
+.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+.\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+.\" OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+.\" IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+.\" INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+.\" NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+.\" DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+.\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+.\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+.\"
+.\" from: lpa.4,v 1.1 1993/08/06 10:34:11 cgd Exp
+.\" $Id$
+.\"
+.Dd August 28, 1993
+.Dt LPA 4 i386
+.Os FreeBSD
+.Sh NAME
+.Nm lpa
+.Nd
+Interruptless parallel port driver
+.Sh SYNOPSIS
+.\" XXX this is awful hackery to get it to work right... -- cgd
+.Cd "device lpa0 at isa? port" \&"IO_LPT1\&" tty
+.Cd "device lpa1 at isa? port" \&"IO_LPT2\&" tty
+.Cd "device lpa2 at isa? port" \&"IO_LPT3\&" tty
+.Sh DESCRIPTION
+This driver provides access to parallel ports. It assumes that
+the parallel port controller will not cause an interrupt, and
+therefore must poll the controller.
+.Sh FILES
+.Bl -tag -width Pa -compact
+.It Pa /dev/lpa0
+first interruptless parallel port driver
+.El
+.Sh SEE ALSO
+.Xr lpt 4
+.Sh BUGS
+This driver only exists to support broken parallel port implementations.
+Systems with properly working parallel ports should use the
+.Nm lpt
+driver instead, as it is less resource-hungry.
+.Pp
+This driver could stand a rewrite.
diff --git a/share/man/man4/man4.i386/lpt.4 b/share/man/man4/man4.i386/lpt.4
new file mode 100644
index 000000000000..070a53e0a008
--- /dev/null
+++ b/share/man/man4/man4.i386/lpt.4
@@ -0,0 +1,59 @@
+.\"
+.\" Copyright (c) 1993 Christopher G. Demetriou
+.\" 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 Christopher G. Demetriou.
+.\" 3. The name of the author may not be used to endorse or promote products
+.\" derived from this software withough specific prior written permission
+.\"
+.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+.\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+.\" OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+.\" IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+.\" INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+.\" NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+.\" DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+.\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+.\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+.\"
+.\" from: lpt.4,v 1.1 1993/08/06 10:34:12 cgd Exp
+.\"
+.Dd August 28, 1993
+.Dt LPT 4 i386
+.Os FreeBSD
+.Sh NAME
+.Nm lpt
+.Nd
+Parallel port driver
+.Sh SYNOPSIS
+.Cd "device lpt0 at isa? port" \&"IO_LPT1\&" tty irq 7 vector lptintr
+.Cd "device lpt1 at isa? port" \&"IO_LPT2\&" tty irq 7 vector lptintr
+.Cd "device lpt2 at isa? port" \&"IO_LPT3\&" tty irq 7 vector lptintr
+.Sh DESCRIPTION
+This driver provides access to parallel ports. It assumes that
+the parallel port controller interrupts the CPU properly. If
+this is not the case, the
+.Nm lpa
+driver should be used instead.
+.Sh FILES
+.Bl -tag -width Pa -compact
+.It Pa /dev/lpt0
+first parallel port driver
+.El
+.Sh SEE ALSO
+.Xr lpa 4
+.Sh BUGS
+There are lots of them, especially in cheap parallel port implementations.
+.Pp
+This driver could stand a rewrite.
diff --git a/share/man/man4/man4.i386/npx.4 b/share/man/man4/man4.i386/npx.4
new file mode 100644
index 000000000000..f904bd19fd87
--- /dev/null
+++ b/share/man/man4/man4.i386/npx.4
@@ -0,0 +1,77 @@
+.\"
+.\" Copyright (c) 1993 Christopher G. Demetriou
+.\" 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 Christopher G. Demetriou.
+.\" 3. The name of the author may not be used to endorse or promote products
+.\" derived from this software withough specific prior written permission
+.\"
+.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+.\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+.\" OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+.\" IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+.\" INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+.\" NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+.\" DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+.\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+.\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+.\"
+.\" from: npx.4,v 1.1 1993/08/06 10:58:03 cgd Exp
+.\" $Id$
+.\"
+.Dd August 28, 1993
+.Dt NPX 4 i386
+.Os FreeBSD
+.Sh NAME
+.Nm npx
+.Nd
+Numeric Processing Extension coprocessor and emulator
+.Sh SYNOPSIS
+.Cd "options MATH_EMULATE"
+.\" XXX this is awful hackery to get it to work right... -- cgd
+.Cd "device npx0 at isa? port" \&"IO_NPX0\&" tty irq 13 vector npxintr
+.Sh DESCRIPTION
+The
+.Nm npx
+driver enables the use of the system's Numeric Processing Extension
+coprocessor,
+if one is present. Numeric processing extensions are present in
+systems with
+.Nm 486DX
+CPUs and in systems with
+.Nm 387
+or
+.Nm 487SX
+coprocessors. The
+.Nm npx
+driver is required for proper system functioning regardless
+of whether or not a NPX is present.
+.Pp
+If there is no NPX present in the system, the "MATH_EMULATE"
+option must be defined in the kernel configuration file.
+It will provide support for the instructions normally executed
+by the NPX. If there is no NPX in the system and the kernel
+is not built with math emulation, the system will not boot.
+.Sh CAVEATS
+The emulator is much slower than the NPX coprocessor.
+This will result in poor floating-point math performance
+if the emulator must be used.
+.Sh BUGS
+There are lots of them, especially on cheap motherboards. In particular,
+some motherboards do not have the interrupt lines from the NPX to
+the CPU wired properly. If this is the case, the emulator must be used
+if consistent system operation is desired.
+.Pp
+Emulation of the transcendental functions instructions is incorrect.
+Emulation of other instructions is suspect.
diff --git a/share/man/man4/man4.i386/sio.4 b/share/man/man4/man4.i386/sio.4
new file mode 100644
index 000000000000..53efb1c22b46
--- /dev/null
+++ b/share/man/man4/man4.i386/sio.4
@@ -0,0 +1,101 @@
+.\" Copyright (c) 1990, 1991 The Regents of the University of California.
+.\" All rights reserved.
+.\"
+.\" This code is derived from software contributed to Berkeley by
+.\" the Systems Programming Group of the University of Utah Computer
+.\" Science Department.
+.\" 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 the University of
+.\" California, Berkeley and its contributors.
+.\" 4. Neither the name of the University nor the names of its contributors
+.\" may be used to endorse or promote products derived from this software
+.\" without specific prior written permission.
+.\"
+.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+.\" SUCH DAMAGE.
+.\"
+.\" from: @(#)dca.4 5.2 (Berkeley) 3/27/91
+.\" from: com.4,v 1.1 1993/08/06 11:19:07 cgd Exp
+.\" $Id$
+.\"
+.Dd August 28, 1993
+.Dt SIO 4 i386
+.Os FreeBSD
+.Sh NAME
+.Nm sio
+.Nd
+fast interrupt serial communications interface
+.Sh SYNOPSIS
+.Cd "device sio0 at isa? port" \&"IO_COM1\&" tty irq 4 vector siointr
+.Cd "device sio1 at isa? port" \&"IO_COM2\&" tty irq 3 vector siointr
+.Cd "device sio2 at isa? port" \&"IO_COM3\&" tty irq 5 vector siointr
+.Cd "device sio3 at isa? port" \&"IO_COM4\&" tty irq 9 vector siointr
+.Sh DESCRIPTION
+The
+.Nm sio
+driver provides support for NS8250-, NS16450-, and NS16550-based
+.Tn EIA
+.Tn RS-232C
+.Pf ( Tn CCITT
+.Tn V.28 )
+communications interfaces. The NS8250 and NS16450 have single character
+buffers, and the NS16550 has a 16 character buffer.
+.Pp
+Input and output for each line may set to one of following baud rates;
+50, 75, 110, 134.5, 150, 300, 600, 1200, 1800, 2400, 4800, 9600,
+19200, 38400, 57600, or 115200.
+.Sh FILES
+.Bl -tag -width Pa
+.It Pa /dev/tty00
+.It Pa /dev/tty01
+.El
+.Sh DIAGNOSTICS
+.Bl -diag
+.It sio%d: silo overflow.
+The single-character input
+.Dq silo
+has overflowed and incoming data has been lost.
+.\".It com%d: weird interrupt: %x.
+.\"The device has generated an unexpected interrupt
+.\"with the code listed.
+.El
+.Sh SEE ALSO
+.Xr tty 4
+.Xr com 4
+.Sh HISTORY
+The
+.Nm
+driver is derived from the
+.Nm HP9000/300
+.Nm dca
+driver and is
+.Ud
+.Sh BUGS
+Data loss is not near as likely on busy systems as they are with the
+.Xr com 4
+driver but they still can occur at very high baud rates on slow systems.
+.Pp
+The constants which define the locations
+of the various seiral ports are holdovers from
+.Nm DOS .
+.Pp
+As usual, you get what you pay for; cheap NS16550 clones
+generally don't work.
diff --git a/share/man/man4/sio.4 b/share/man/man4/sio.4
new file mode 100644
index 000000000000..53efb1c22b46
--- /dev/null
+++ b/share/man/man4/sio.4
@@ -0,0 +1,101 @@
+.\" Copyright (c) 1990, 1991 The Regents of the University of California.
+.\" All rights reserved.
+.\"
+.\" This code is derived from software contributed to Berkeley by
+.\" the Systems Programming Group of the University of Utah Computer
+.\" Science Department.
+.\" 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 the University of
+.\" California, Berkeley and its contributors.
+.\" 4. Neither the name of the University nor the names of its contributors
+.\" may be used to endorse or promote products derived from this software
+.\" without specific prior written permission.
+.\"
+.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+.\" SUCH DAMAGE.
+.\"
+.\" from: @(#)dca.4 5.2 (Berkeley) 3/27/91
+.\" from: com.4,v 1.1 1993/08/06 11:19:07 cgd Exp
+.\" $Id$
+.\"
+.Dd August 28, 1993
+.Dt SIO 4 i386
+.Os FreeBSD
+.Sh NAME
+.Nm sio
+.Nd
+fast interrupt serial communications interface
+.Sh SYNOPSIS
+.Cd "device sio0 at isa? port" \&"IO_COM1\&" tty irq 4 vector siointr
+.Cd "device sio1 at isa? port" \&"IO_COM2\&" tty irq 3 vector siointr
+.Cd "device sio2 at isa? port" \&"IO_COM3\&" tty irq 5 vector siointr
+.Cd "device sio3 at isa? port" \&"IO_COM4\&" tty irq 9 vector siointr
+.Sh DESCRIPTION
+The
+.Nm sio
+driver provides support for NS8250-, NS16450-, and NS16550-based
+.Tn EIA
+.Tn RS-232C
+.Pf ( Tn CCITT
+.Tn V.28 )
+communications interfaces. The NS8250 and NS16450 have single character
+buffers, and the NS16550 has a 16 character buffer.
+.Pp
+Input and output for each line may set to one of following baud rates;
+50, 75, 110, 134.5, 150, 300, 600, 1200, 1800, 2400, 4800, 9600,
+19200, 38400, 57600, or 115200.
+.Sh FILES
+.Bl -tag -width Pa
+.It Pa /dev/tty00
+.It Pa /dev/tty01
+.El
+.Sh DIAGNOSTICS
+.Bl -diag
+.It sio%d: silo overflow.
+The single-character input
+.Dq silo
+has overflowed and incoming data has been lost.
+.\".It com%d: weird interrupt: %x.
+.\"The device has generated an unexpected interrupt
+.\"with the code listed.
+.El
+.Sh SEE ALSO
+.Xr tty 4
+.Xr com 4
+.Sh HISTORY
+The
+.Nm
+driver is derived from the
+.Nm HP9000/300
+.Nm dca
+driver and is
+.Ud
+.Sh BUGS
+Data loss is not near as likely on busy systems as they are with the
+.Xr com 4
+driver but they still can occur at very high baud rates on slow systems.
+.Pp
+The constants which define the locations
+of the various seiral ports are holdovers from
+.Nm DOS .
+.Pp
+As usual, you get what you pay for; cheap NS16550 clones
+generally don't work.