xref: /freebsd/share/man/man9/owll.9 (revision 93e779a26c651610ac6e7986d67ecc9ed2cadcbf)
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27.Dd July 20, 2015
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 bitor 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