xref: /netbsd/share/man/man4/spi.4 (revision 6550d01e)
1.\"	$NetBSD: spi.4,v 1.4 2009/05/27 19:24:00 snj Exp $
2.\"
3.\" Copyright (c) 2006 Urbana-Champaign Independent Media Center.
4.\" Copyright (c) 2006 Garrett D'Amore.
5.\" All rights reserved.
6.\"
7.\" Portions of this code were written by Garrett D'Amore for the
8.\" Champaign-Urbana Community Wireless Network Project.
9.\"
10.\" Redistribution and use in source and binary forms, with or
11.\" without modification, are permitted provided that the following
12.\" conditions are met:
13.\" 1. Redistributions of source code must retain the above copyright
14.\"    notice, this list of conditions and the following disclaimer.
15.\" 2. Redistributions in binary form must reproduce the above
16.\"    copyright notice, this list of conditions and the following
17.\"    disclaimer in the documentation and/or other materials provided
18.\"    with the distribution.
19.\" 3. All advertising materials mentioning features or use of this
20.\"    software must display the following acknowledgements:
21.\"      This product includes software developed by the Urbana-Champaign
22.\"      Independent Media Center.
23.\"	This product includes software developed by Garrett D'Amore.
24.\" 4. Urbana-Champaign Independent Media Center's name and Garrett
25.\"    D'Amore's name may not be used to endorse or promote products
26.\"    derived from this software without specific prior written permission.
27.\"
28.\" THIS SOFTWARE IS PROVIDED BY THE URBANA-CHAMPAIGN INDEPENDENT
29.\" MEDIA CENTER AND GARRETT D'AMORE ``AS IS'' AND ANY EXPRESS OR
30.\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
31.\" WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
32.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE URBANA-CHAMPAIGN INDEPENDENT
33.\" MEDIA CENTER OR GARRETT D'AMORE BE LIABLE FOR ANY DIRECT, INDIRECT,
34.\" INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
35.\" NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
36.\" LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
37.\" CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
38.\" STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
39.\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
40.\" ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
41.\"
42.Dd October 9, 2006
43.Dt SPI 4
44.Os
45.Sh NAME
46.Nm spi
47.Nd introduction to machine-independent SPI bus support and drivers
48.Sh SYNOPSIS
49.Cd "spi* at mainbus?"
50.Pp
51Other attachments are machine-dependent and will depend on the bus topology
52of your system.
53See
54.Xr intro 4
55for your system for more information.
56.Sh DESCRIPTION
57.Nx
58includes a machine dependent
59.Tn SPI
60(Serial Peripheral Interface) bus subsystem, and several different
61machine-independent
62.Tn SPI
63device drivers.
64.Pp
65Your system may support additional machine-dependent SPI devices.
66Consult your system's
67.Xr intro 4
68for additional information.
69.Pp
70.Tn SPI
71is a 4-wire synchronous full-duplex serial bus.
72Some systems provide support for
73.Tn Microwire ,
74which is
75.Tn Philips'
76name for a strict subset of SPI, with more rigidly defined signaling.
77Therefore,
78.Tn Microwire
79devices are also supported by the
80.Tn SPI
81framework.
82.Pp
83Note that when referencing
84.Tn SPI
85devices in a
86.Xr config 1
87file, the
88.Sq slave
89must be provided, as
90.Tn SPI
91lacks any way to automatically probe devices.
92.Sh HARDWARE
93.Nx
94includes the following machine-independent
95.Tn SPI
96drivers
97.Bl -tag -width pcdisplay -offset indent
98.It m25p
99STMicroelectronics M25P family of NOR flash devices.
100.It tm121temp
101Texas Instruments TMP121 temperature sensor.
102.El
103.Sh SEE ALSO
104.Xr m25p 4 ,
105.Xr tm121temp 4
106.Sh HISTORY
107The machine-independent
108.Tn SPI
109framework was written by
110.An Garrett D'Amore
111for the
112Champaign-Urbana Community Wireless Network Project (CUWiN), and
113appeared in
114.Nx 4.0 .
115