.\" Copyright (c) 1998, Nicolas Souchu
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.\" $FreeBSD: src/share/man/man4/man4.i386/pcf.4,v 1.9.2.3 2001/08/17 13:08:46 ru Exp $
.\"
.Dd August 6, 1998
.Dt PCF 4
.Os
.Sh NAME
.Nm pcf
.Nd Philips I2C bus controller
.Sh SYNOPSIS
.Cd "device pcf0 at isa? port? irq 5"
.Pp
For one or more iicbus busses:
.Cd "device iicbus"
.Sh DESCRIPTION
The
.Em pcf
driver provides support to the Philips PCF8584 I2C controller for the
.Xr iicbus 4
system.
.Pp
The PCF8584 is an integrated circuit designed in CMOS technology which serves
as an interface between most standard parallel-bus
microcontrollers/microprocessors and the serial I2C-bus.
The PCF8584
provides both master and slave functions.
Communication with I2C-bus is
carried out on a byte-wise basis using interrupt or polled handshake.
It
controls all the I2C-bus specific sequences, protocol, arbitration and timing.
The PCF8584 allows parallel-bus systems to communicate bidirectionally with
the I2C-bus.
.Sh SEE ALSO
.Xr iicbus 4
.Sh HISTORY
The
.Nm
manual page first appeared in
.Fx 3.0 .
.Sh AUTHORS
This
manual page was written by
.An Nicolas Souchu .