1.\" $NetBSD: hythygtemp.4,v 1.4 2015/09/09 17:42:35 wiz Exp $ 2.\" 3.\" Copyright (c) 2014 Frank Kardel 4.\" All rights reserved. 5.\" 6.\" Redistribution and use in source and binary forms, with or without 7.\" modification, are permitted provided that the following conditions 8.\" are met: 9.\" 1. Redistributions of source code must retain the above copyright 10.\" notice, this list of conditions and the following disclaimer. 11.\" 2. Redistributions in binary form must reproduce the above copyright 12.\" notice, this list of conditions and the following disclaimer in the 13.\" documentation and/or other materials provided with the distribution. 14.\" 15.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS 16.\" ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 17.\" TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 18.\" PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 19.\" BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 20.\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 21.\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 22.\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 23.\" CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 24.\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 25.\" POSSIBILITY OF SUCH DAMAGE. 26.\" 27.Dd September 9, 2015 28.Dt HYTHYGTEMP 4 29.Os 30.Sh NAME 31.Nm hythygtemp 32.Nd Driver for IST-AG HYT-221/271/939 sensor chip via I2C bus 33.Sh SYNOPSIS 34.Cd "hythygtemp* at iic? addr 0x28" 35.Sh DESCRIPTION 36The 37.Nm 38driver provides measurements from the HYT-221/271/939 humidity/temperature 39sensors via the 40.Xr envsys 4 41framework. 42The 43.Nm 44.Ar addr 45argument selects the address at the 46.Xr iic 4 47bus. 48The sampling interval can be changed through the 49.Xr sysctl 8 50node 51.Li hw.hythygtemp0.interval . 52.Pp 53The sensor chips can be reconfigured to respond to other addresses than the 54default value of 0x28 by external utilities, like for example the 55.Pa pkgsrc/sysutils/hytctl 56package. 57.Sh SYSCTL VARIABLES 58The following 59.Xr sysctl 3 60variables are provided: 61.Bl -tag -width indent 62.It hw.hythygtemp0.interval 63Defines the sensor's sampling interval in seconds. 64It defaults to 50 seconds. 65.El 66.Sh SEE ALSO 67.Xr envsys 4 , 68.Xr iic 4 , 69.Xr envstat 8 , 70.Xr sysctl 8 71.Sh HISTORY 72The 73.Nm 74driver first appeared in 75.Nx 7.0 . 76.Sh AUTHORS 77.An -nosplit 78The 79.Nm 80driver was written by 81.An Frank Kardel Aq Mt kardel@NetBSD.org 82and 83.An Frank Wille Aq phx@NetBSD.org . 84