---
name: "pcf"
section: "4"
platform: "linux"
package: "freebsd-manpages"
version: "6.0-5"
release: "Debian 4.0 (Etch)"
platforms: ["linux", "freebsd"]
url: "https://new.carta.tech/pcf"
---

# pcf(4)

Philips I2C bus controller

## NAME

**pcf** – Philips I2C bus controller

## SYNOPSIS

**device pcf**

In */boot/device.hints*: **hint.pcf.0.at="isa"** **hint.pcf.0.port="0x320"** **hint.pcf.0.irq="5"**

For one or more iicbus busses: **device iicbus**

## DESCRIPTION

The *pcf* driver provides support to the Philips PCF8584 I2C controller for the [iicbus(4)](/iicbus/4.md) system.

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.

## SEE ALSO

[iicbus(4)](/iicbus/4.md)

## HISTORY

The **pcf** manual page first appeared in FreeBSD 3.0.

## AUTHORS

This manual page was written by Nicolas Souchu.