1.\" $NetBSD: gpioow.4,v 1.2 2006/04/08 23:10:40 wiz Exp $ 2.\" $OpenBSD: gpioow.4,v 1.3 2006/03/06 10:24:46 grange Exp $ 3.\" 4.\" Copyright (c) 2006 Alexander Yurchenko <grange@openbsd.org> 5.\" 6.\" Permission to use, copy, modify, and distribute this software for any 7.\" purpose with or without fee is hereby granted, provided that the above 8.\" copyright notice and this permission notice appear in all copies. 9.\" 10.\" THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 11.\" WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 12.\" MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR 13.\" ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 14.\" WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 15.\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 16.\" OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 17.\" 18.Dd March 4, 2006 19.Dt GPIOOW 4 20.Os 21.Sh NAME 22.Nm gpioow 23.Nd 1-Wire bus bit-banging through GPIO pin 24.Sh SYNOPSIS 25.Cd "gpioow* at gpio? offset 0 mask 0x1" 26.Cd "onewire* at gpioow?" 27.Sh DESCRIPTION 28The 29.Nm 30driver allows bit-banging a 1-Wire bus as a master using one GPIO pin. 31The pin is used as a data signal. 32The GPIO pin must be able to drive an output and read an input. 33.Pp 34The pin number is specified in the kernel configuration with the 35.Ar offset 36locator. 37The 38.Ar mask 39locator should always be 0x1. 40.Sh SEE ALSO 41.Xr gpio 4 , 42.Xr intro 4 , 43.Xr onewire 4 44.Sh HISTORY 45The 46.Nm 47driver first appeared in 48.Ox 4.0 49and 50.Nx 4.0 . 51.Sh AUTHORS 52.An -nosplit 53The 54.Nm 55driver was written by 56.An Alexander Yurchenko Aq grange@openbsd.org 57and was ported to 58.Nx 59by 60.An Jeff Rizzo Aq riz@NetBSD.org . 61