xref: /netbsd-src/share/man/man4/intersil7170.4 (revision aaf4ece63a859a04e37cf3a7229b5fab0157cc06)
1.\"	$NetBSD: intersil7170.4,v 1.9 2003/06/27 18:32:02 wiz Exp $
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3.\" Copyright (c) 2000 The NetBSD Foundation, Inc.
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6.\" This code is derived from software contributed to The NetBSD Foundation
7.\" by Paul Kranenburg.
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37.Dd July 20, 2000
38.Dt INTERSIL7170 4
39.Os
40.Sh NAME
41.Nm intersil7170
42.Nd
43.Tn Intersil time-of-day clock driver
44.Sh SYNOPSIS
45.In dev/ic/intersil7170.h
46.Cd "define intersil7170"
47.Cd "file   dev/ic/intersil7170.c    intersil7170"
48.Sh DESCRIPTION
49The
50.Nm
51driver provides access to the
52.Tn Intersil 7170
53time-of-day clock chip.
54Access methods to retrieve and set date and time
55are provided through the
56.Em TODR
57interface defined in
58.Xr todr 9 .
59.Pp
60To tie an instance of this device to the system, use
61.Pp
62.Ft "todr_chip_handle_t"
63.Fn intersil7170_attach "bus_space_tag_t bus_tag" \
64"bus_space_handle_t bus_handle" "int year0"
65.Pp
66.Bl -tag -width Dv -offset indent
67.It Fa bus_tag
68.It Fa bus_handle
69Specify bus space access to the chip's non-volatile memory
70.Pq including the clock registers .
71.It Fa year0
72The actual year represented by the clock's
73.Sq year
74counter.
75This is generally dependent on the system configuration in which
76the clock device is mounted.
77For instance, on Sun Microsystems machines
78the convention is to have clock's two-digit year represent the year 1968.
79.El
80.Pp
81Note that if the resulting date retrieved with the todr_gettime() method
82is earlier that January 1, 1970, the driver will assume that the chip's
83year counter actually represents a year in the 21st century.
84This behaviour can be overridden by setting the global variable
85.Va intersil7170_auto_century_adjust
86to zero.
87.Sh SEE ALSO
88.Xr intro 4 ,
89.Xr todr 9
90.Sh HISTORY
91The
92.Nm
93driver first appeared in
94.Nx 1.5 .
95.Sh AUTHORS
96The
97.Nm
98driver was written by
99.An Paul Kranenburg
100.Aq pk@NetBSD.org .
101