User guide

Overview

CS4953x4/CS4970x4 System Designer’s Guide

Chapter 1

Operational Modes

1.1 Overview

The CS4953x4/CS4970x4 DSP has several operational modes that can be used to conform to many

system configurations. The DSP is configured to Master Boot as shown in Figure 1-1 in order to simplify

connectivity and to reduce the complexity of the microcontroller code used in the system.

Figure 1-1. Operation Mode Block Diagram

The DSP is configured to boot from external serial SPI Flash when reset is released. Once the DSP is

booted, it turns into an intelligent Slave device. The DSP will swap out decoders from external SPI Flash

when stream changes without the necessity of interacting with the host. The DSP will change any mid- or

post-processing module with a single command from the host. The DSP takes on most of the control

functionality from the microcontroller. This significantly reduces the microcontroller development effort

thereby reducing time to market of the end product.

1.1.1 Supported Serial Flash Devices

Cirrus logic recommends SPI serial flash devices with a minimum storage capacity of 8 Mbits. The Cirrus

recommended flash devices are:

• SST25VF080B (tested) - See the data sheet for this device at:

http://www.microchip.com/wwwproducts/Devices.aspx?dDocName=en549423

• EN25P32 (tested) - See the data sheet for this device at:

http://www.eonssi.com/upfile/p2008929182330.pdf

• M25P80 (tested) - See the data sheet for this device at:

http://www.icbase.com/pdf/STM/STM30070501.pdf

• SST25LFxxx

• AT45DB041D - See the data sheet for this device at:

CS4953x4/CS4970x4

(Master at Boot,

Intelligent Slave after

Boot)

Ext. Serial Flash

SCP2

System Host

Controller

(Master after

Boot)

SCP1

Control Bus

(SPI or 1

(SPI)