Fast Infrared Interface; Overview; Signals - Intel PXA27 Series Design Manual

Fast Infrared Interface

This chapter describes guidelines for interfacing with the external LED transceivers to fast infrared
(FIR) controller of Intel
11.1

Overview

The Fast Infrared Communications Port (FICP) operates at half-duplex and provides direct
connection to commercially available Infrared Data Association (IrDA) compliant LED
transceivers. The FICP is based on the 4 Mbps IrDA standard
modulation (4 PPM) and a specialized serial packet protocol developed for IrDA transmission. To
support the standard, the FICP is equipped with:
•
A bit encoder/decoder
•
A serial-to-parallel data engine
•
A transmit First In/First Out (FIFO) 64 entries deep and 8-bits wide
•
A receive FIFO 64 entries deep and 11-bits wide
The FICP shares GPIO pins for transmit and receive data with the standard UART and the
Bluetooth UART. Only two of these three ports, which are FICP, STUART, and BTUART, are used
at any one time. To support a variety of IrDA transceivers, both the transmit and receive data pins
are individually configured to communicate using normal or active low data.
11.2

Signals

See Table 11-1
enable and speed pins. Use GPIOs or control signals from external logic to enable the transceiver
and select the speed
Table 11-1. FICP Signal Description
Signal Name Input/Output
ICP_RXD
ICP_TXD
1. Refer to Infrared Data Association Serial Infrared Physical Layer Specification Version 1.3, October 15, 1998 available from
®
Intel PXA27x Processor Family Design Guide
®
PXA27x Processor Family (PXA27x processor).
for description of the function of each signal. Most IrDA transceivers also have
Description
Input Receive pin for FICP
Output Transmit pin for FICP
Fast Infrared Interface
1
and uses four-position pulse
11
www.irda.org
II:11-1