1.\" 2.\" Copyright (c) 2015 M. Warner Losh 3.\" All rights reserved. 4.\" 5.\" Redistribution and use in source and binary forms, with or without 6.\" modification, are permitted provided that the following conditions 7.\" are met: 8.\" 1. Redistributions of source code must retain the above copyright 9.\" notice, this list of conditions and the following disclaimer. 10.\" 2. The name of the author may not be used to endorse or promote products 11.\" derived from this software without specific prior written permission. 12.\" 13.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 14.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 15.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 16.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 17.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 18.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 19.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 20.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 21.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 22.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 23.\" SUCH DAMAGE. 24.\" 25.\" $FreeBSD$ 26.\" 27.Dd September 22, 2016 28.Dt OWLL 9 29.Os 30.Sh NAME 31.Nm owll 32.Nm OWLL_WRITE_ONE, 33.Nm OWLL_WRITE_ZERO, 34.Nm OWLL_READ_DATA, 35.Nm OWLL_REASET_AND_PRESENCE 36.Nd Dallas Semiconductor 1-Wire Link Layer Interface 37.Sh SYNOPSIS 38.Ft int 39.Fn OWLL_WRITE_ONE "device_t lldev" "struct ow_timing *timing" 40.Ft int 41.Fn OWLL_WRITE_ZERO "device_t lldev" "struct ow_timing *timing" 42.Ft int 43.Fn OWLL_READ_DATA "device_t lldev" "struct ow_timing *timing" "int *bit" 44.Ft int 45.Fn OWLL_RESET_AND_PRESENCE "device_t lldev" "struct ow_timing *timing" "int *bit" 46.Sh DESCRIPTION 47The 48.Nm 49interface provides access to the link layer of the Dallas 50Semiconductor 1-Wire from upper layers of the protocol. 51.Pp 52.Fn OWLL_WRITE_ONE 53and 54.Fn OWLL_WRITE_ZERO 55writes a one bit or a zero bit respectively on the 1-Wire bus. 56.Pp 57.Fn OWLL_READ_DATA 58reads one bit from the 1-Wire bus. 59This is often referred to as a 60.Dq Read Time Slot 61in the 1-Wire device data sheets. 62.Pp 63The 64.Fn OWLL_RESET_AND_PRESENCE 65function starts a reset sequence and detects if any device(s) are 66present on the bus. 67This is the beginning of all 1-Wire transactions. 68.Sh NOTES 69This interface is intended to be used only by the 70.Xr ow 4 71device to talk to the low-level bus. 72By convention, the device that implements this interface is called 73.Xr owc 4 . 74Only devices that implement 75.Xr own 9 76should call these interfaces. 77.Sh SEE ALSO 78.Xr ow 4 , 79.Xr owc 4 , 80.Xr own 9 81.Sh LEGAL 82.Tn 1-Wire 83is a registered trademark of Maxim Integrated Products, Inc. 84.Sh HISTORY 85The 86.Nm 87driver first appeared in 88.Fx 11.0 . 89.Sh AUTHORS 90The 91.Nm 92device driver and this manual page were written by 93.An Warner Losh . 94