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1 overview, 2 features – Intel PXA26X User Manual

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Intel® PXA26x Processor Family Developer’s Manual

16-1

Network/Audio Synchronous Serial
Protocol Serial Ports

16

This chapter describes the signal definitions and operation of the Intel® PXA26x Processor Family
Network and Audio Synchronous Serial Protocol (SSP) serial ports. The Network SSP (NSSP) and
Audio SSP (ASSP) are similar except for the following:

External pin connections

Memory map base location

The Network ASSP supports swapping the receive and transmit data pins. See

Section 4.1,

“General-Purpose Input/Output” on page 4-1

.

The NSSP and ASSP are configured differently than the SSPC.

16.1

Overview

The NSSP and ASSP ports are a synchronous serial interface that connect to a variety of external
analog-to-digital (A/D) converters, audio and telecommunication CODECs, and many other
devices that use serial protocols for data transfer. The SSP ports provide support for the following
protocols:

Texas Instruments (TI) Synchronous Serial Protocol*

Motorola Serial Peripheral Interface* (SPI) protocol

National Semiconductor Microwire*

Programmable Serial Protocol (PSP)

The NSSP and ASSP ports operate as full-duplex devices for the TI Synchronous Serial Protocol*,
SPI*, and PSP protocols and as half-duplex devices for the Microwire* protocol.

The FIFOs can be loaded or emptied by the CPU using programmed I/O or DMA burst transfers.

16.2

Features

Supports the TI Synchronous Serial Protocol*, the Motorola SPI* protocol, National
Semiconductor Microwire*, and a Programmable Serial Protocol (PSP)

Two independent transmit and receive FIFOs, each 16 samples deep by 32-bits wide

Sample sizes from four to 32-bits

Maximum bit rate of 13 Mbps in slave of clock mode, requires using DMA

Master-mode and slave-mode operation

Receive-without-transmit operation