xref: /freebsd/share/man/man4/pcf.4 (revision 1670a1c2a47d10ecccd001970b859caf93cd3b6e)
1.\" Copyright (c) 1998, Nicolas Souchu
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25.\" $FreeBSD$
26.\"
27.Dd August 6, 1998
28.Dt PCF 4
29.Os
30.Sh NAME
31.Nm pcf
32.Nd Philips I2C bus controller
33.Sh SYNOPSIS
34.Cd "device pcf"
35.Pp
36In
37.Pa /boot/device.hints :
38.Cd hint.pcf.0.at="isa"
39.Cd hint.pcf.0.port="0x320"
40.Cd hint.pcf.0.irq="5"
41.Pp
42For one or more iicbus busses:
43.Cd "device iicbus"
44.Sh DESCRIPTION
45The
46.Em pcf
47driver provides support to the Philips PCF8584 I2C controller for the
48.Xr iicbus 4
49system.
50.Pp
51The PCF8584 is an integrated circuit designed in CMOS technology which serves
52as an interface between most standard parallel-bus
53microcontrollers/microprocessors and the serial I2C-bus.
54The PCF8584
55provides both master and slave functions.
56Communication with I2C-bus is
57carried out on a byte-wise basis using interrupt or polled handshake.
58It
59controls all the I2C-bus specific sequences, protocol, arbitration and timing.
60The PCF8584 allows parallel-bus systems to communicate bidirectionally with
61the I2C-bus.
62.Sh SEE ALSO
63.Xr iicbus 4
64.Sh HISTORY
65The
66.Nm
67manual page first appeared in
68.Fx 3.0 .
69.Sh AUTHORS
70This
71manual page was written by
72.An Nicolas Souchu .
73