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