1.\" $NetBSD: spi.4,v 1.7 2019/02/23 17:34:04 wiz 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 mcp23s17gpio 101Microchip MCP23S17 16-bit GPIO chip. 102.It mcp3kadc 103Microchip MCP3x0x SAR analog to digital converter. 104.It mcp48x1dac 105Microchip MCP4801/MCP4811/MCP4821 digital to analog converter. 106.It tm121temp 107Texas Instruments TMP121 temperature sensor. 108.El 109.Sh SEE ALSO 110.Xr m25p 4 , 111.Xr mcp23s17gpio 4 , 112.Xr mcp3kadc 4 , 113.Xr mcp48x1dac 4 , 114.Xr tm121temp 4 , 115.Xr spi 9 116.Sh HISTORY 117The machine-independent 118.Tn SPI 119framework was written by 120.An Garrett D'Amore 121for the 122Champaign-Urbana Community Wireless Network Project (CUWiN), and 123appeared in 124.Nx 4.0 . 125