Cirrus Logic CDB8427 User Manual

Evaluation Board for CS8427

CDB8427

Features

Receives and transmits AES/EBU, S/PDIF

and EIAJ-340 compatible digital audio Convenient access to the Serial Audio Input

Port and Serial Audio Output Port through headers.

Runs from a single 5 Volt supply.

Crystal supplied to allow operation at 48 kHz,

sample rate. Digital patch area.

Description

The CDB8427 is designed to allow rapid evaluation of the CS8427. The board is set up for easy connection to an Audio Precision or a Rohde and Schwarz test system.

Input and output data formats may independently be set to either AES/EBU, or S/PDIF with either optical or coaxial physical format.

Separate headers are provided so the Serial Audio Input Port and Serial Audio Output Port may be interfaced to off board circuits.

Microsoft interface to make configuration easy. The software communicates through the PC’s RS232 port to a microcontroller on the evaluation board that controls the CS8427. All the possible software modes of the CS8427 may be tested.

ORDERING INFORMATION

Windows® 98 PC software provides a GUI

CDB8427 Evaluation Board

Amtel

µC

Optical In

S/PDIF In

AES 3 In

Preliminary Product Information

Cirrus Logic, Inc.

P.O. Box 17847, Austin, Texas 78760 (512) 445 7222 FAX: (512) 445 7581 http://www.cirrus.com

RS232 port to PC

Optical Out

CS8427

S/PDIF Out

AES 3 Out

This document contains information for a new product. Cirrus Logic reserves the right to modify this product without notice.

DS477DB2

AUG ‘02

TABLE OF CONTENTS

1. OVERVIEW ............................................................................................................................... 3

1.1 CS8427 .............................................................................................................................. 3

1.2 Microcontroller and Memory .............................................................................................. 3

1.3 Crystal Oscillators .............................................................................................................. 3

1.4 RS232 Port ........................................................................................................................ 3

1.5 LED Function Indicators ..................................................................................................... 3

2. CDB8427.EXE QUICK START GUIDE .................................................................................... 4

2.1 Setting up the Hardware ....................................................................................................4

2.2 Installing the Software ........................................................................................................ 4

2.3 Starting up the Software .................................................................................................... 4

2.4 Starting up the Hardware ...................................................................................................4

3. CDB8427.EXE USER'S GUIDE ................................................................................................ 6

3.1 Main Window ..................................................................................................................... 6

3.2 Board Setup ....................................................................................................................... 7

3.3 Script file syntax ................................................................................................................. 7

LIST OF FIGURES

Figure 1. CDB8427 Control Panel Main Window ............................................................................ 6

Figure 2. Board Setup Panel ........................................................................................................... 7

Figure 3. CS8427 Digital Audio Transceiver ................................................................................... 9

Figure 4. Atmel AVR RISC Microcontroller ................................................................................... 10

Figure 5. Power Supplies and Reset Circuit.................................................................................. 11

Figure 6. Silkscreen....................................................................................................................... 12

Figure 7. Top PCB......................................................................................................................... 13

Figure 8. Bottom PCB ................................................................................................................... 14

CDB8427

LIST OF TABLES

Table 1. System Connections ......................................................................................................... 5

Table 2. CDB8427 Jumper Settings................................................................................................5

Table 3. Script file syntax description.............................................................................................. 7

Contacting Cirrus Logic Support

For a complete listing of Direct Sales, Distributor, and Sales Representative contacts, visit the Cirrus Logic web site at:

http://www.cirrus.com/corporate/contacts/sales.cfm

IMPORTANT NOTICE

“Preliminary” product information describes products that are in production, but for which full characterization data is not yet available. “Advance” product information describes products that are in development and subject to development changes. Cirrus Logic, Inc. and its subsidiaries (“Cirrus ”) b elie ve that the in formation contained in this document is accurate and reliable. However, the information is subject to change without notice and is provided “AS IS” without warranty of any kind (express or implied). Customers are advised to obtain the latest version of relevant information to verify, before placing orders, that information being relied on is current and complete. All products are sold subject to the terms and conditions of sale supplied at the time of order acknowledgment, including those pertaining to warranty, patent infringement, and limitation of liability. N o res po nsibility is a ss um ed b y C irrus for the use of this inform a tion, in clu din g use o f this information as the basis for manufacture or sale of any items, or for infringement of patents or other rights of third parties. This document is the property of Cirrus and by furnishing this information, Cirrus grants no license, express or implied under any patents, mask work rights, copyrights, trademarks, trade secrets or other intellectual property rights. Cirrus owns the copyrights of the information contained herein and gives consent for copies to be made of the information only for use within your organization with respect to Cirrus integrated circuits or other parts of Cirrus. This consent does not extend to other copying such as copying for general distribution, advertising or promotional purposes, or for creating any work for resale.

An export permit needs to be obtained from the competent authorities of the Japanese Government if any of the products or technologies described in this material and controlled under the “Foreign Exchange and Foreign Trade Law” is to be exported or taken out of Japan. An export license and/or quota needs to be obtained from the competent authorities of the Chinese Government if any of the products or technologies described in this material is subject to the PRC Foreign Trade Law and is to be exported or taken out of the PRC.

CERTAIN APPLICATIONS USING SEMICONDUCTOR PRODUCTS MAY INVOLVE POTENTIAL RISKS OF DEATH, PERSONAL INJURY, OR SEVERE PROPERTY OR ENVIRONMENTAL DAMAGE (“CRITICAL APPLICATIONS”). CIRRUS PRODUCTS ARE NOT DESIGNED, AUTHORIZED, OR WARRANTED TO BE SUITABLE FOR USE IN LIFE-SUPPORT DEVICES OR SYSTEMS OR OTHER CRITICAL APPLICATIONS. INCLUSION OF CIRRUS PRODUCTS IN SUCH APPLICATIONS IS UNDERSTOOD TO BE FULLY AT THE CUSTOMER'S RISK.

Cirrus Logic, Cirrus, and the Cirrus Logic logo designs are trademarks of Cirrus Logic, Inc. All other brand and product names in this document may be trademarks or service marks of their respective owners.

1. OVERVIEW

CDB8427

The CDB8427 evaluation board contains a CS8427 and the supporting circuitry necessary for it to operate. The input and output options include AES3 and S/PDIF in optical and coaxial formats. In software mode, the control registers of the CS8427 are set by an Atmel AVR RISC microcontroller. A Microsoft Windows 98 based program communicates with the micro through an RS232 port to control the configuration.

1.1 CS8427

The features and functions of the CS8427 are described in its data sheet.

1.2 Microcontroller and Memory

The functions of the board are controlled by an Atmel AVR RISC microcontroller. The board is equipped with 512 KBytes of static RAM so that Channel Status and User bits from the AES stream may be captured and uploaded to the host PC. The microcontroller communicates with the CS8427 through its SPI port. The Atmel AVR RISC microcontroller may be bypassed in order to utilize an external microcontroller through header J10. Header J9 allows the microcontroller on the board to be programmed with the programmer that is supplied in the Atmel STK-300 development kit. Additional software development tools and applications information for the Atmel microcontroller are available at: http://www.atmel.com.

1.3 Crystal Oscillators

There are positions for two crystal oscillators on the board. Both locations are equipped with pin sockets that allow the oscillators to be removed. The oscillator labeled U10 provides the 6 MHz clock for the microcontroller and should not be changed unless you plan on reprogramming the micro.

U3 is the oscillator that provides the Output Master Clock for the CS8427. The board is shipped with a

12.288 MHz crystal oscillator that can be stuffed at U3 to set the output sampling rate to 48 kHz.

1.4 RS232 Port

The RS232 port on the upper right hand side of the board should be connected to the serial port of the PC running the CDB8427 control software. Follow the software instructions to properly configure the serial port for use with the evaluation board.

1.5 LED Function Indicators

LEDs D8 and D9 on the upper right hand corner of the board allow the user to determine when data is being transmitted over the RS232 link. The red LED D4 is the reset indicator and the red LED D1 is connected to the RERR pin of the CS8427. The two remaining LEDs on the board are not currently of use to the end user

CDB8427

2. CDB8427.EXE QUICK START GUIDE

2.1 Setting up the Hardware

Note: SeeTable 1 on page 5 and Table 2 on page 5 for

the configuration and jumper settings.

1) Connect the CDB8427 to a 5 V DC power supply.

2) Set: J11 to Optical, J16 to S/PDIF, enable J13 (S/PDIF), and disable J15 (MUTE).

3) Connect the CDB8427 to the PC COM port using RS232 cable.

4) Apply power to the board.

5) Press the RESET switch (S5).

At this point, the RERR and PROC should be lit. The hardware is now ready!

2.2 Installing the Software

1) Create a directory called CDB8427 anywhere on your system.

2) Copy CDB8427.exe into this directory.

3) If you do not already have them, copy the included DLLs msvcrt.dll and mfc42.dll into your \Windows\System directory.

4) If desired, create a shortcut to CDB8427.exe on your desktop.

At this point, you are ready to start up the software.

2.3 Starting up the Software

1) Double-click on CDB8427.exe or its shortcut.

2) If you get errors right away, the COM port needs to be set properly.

3) Click anywhere but inside one of the boxes, this brings up the Board Setup control panel.

4) Select the COM port you are using to connect to the CDB8427.

5) Shut down the application, reset the board, and then restart the application.

2.4 Starting up the Hardware

1) Click anywhere but inside one of the boxes, this brings up the Board Setup control panel.

2) Click on the Reset button. You should see the TX and RX leds light up briefly.

3) Click on the AES3 Transmitter tab, then set the Transmitter data source to AES3 Receiver.

4) Click on the Clock Sources tab, click on RMCK derived from AES3 input frame and uncheck the Stop Internal Clocks box.

5) Check the performance of the board by doing an FFT with a -1dBFS 1kHz sine wave for input at 44.1kHz and 48kHz sample rates using the optical input and optical output.

CDB8427

CONNECTOR INPUT/OUTPUT SIGNAL PRESENT

+5V Input +5 Volt power

GND Input Ground connection from power supply

OPTICAL INPUT Input Digital Audio Interface optical input

S/PDIF INPUT Input Digital Audio Interface coaxial input

AES3 INPUT Input Digital Audio Interface XLR input

RS232 Input/Output Parallel RS232 port for connection to serial port of PC

OPTICAL OUTPUT Output Digital Audio Interface optical output (always enabled)

S/PDIF OUTPUT Output Digital Audio Interface coaxial output

AES3 OUTPUT Output Digital Audio Interface XLR output

J5 Input/Output I/O for RMCLK, ISCLK,ILRCK, and SDIN J6 Input/Output I/O for OLRCK, OSCLK, OMCK, and SDOUT J9 Input 10-pin header for external programming of Atmel AVR µC

J10 Input/Output 12-pin header for CS8427 control from external µC

Table 1. System Connections

JUMPER PURPOSE POSITION FUNCTION SELECTED

J11 Selects physical format of digital

audio interface input

J12 Configures AES3 INPUT ENABLE

J13 Configures S/PDIF INPUT ENABLE

J14 Configures OPTICAL INPUT ENABLE

J16 Selects physical format of digital

audio interface output

J17 Configures S/PDFIF OUTPUT ENABLE

J15 Configures HARDWARE MODE

MUTE

Table 2. CDB8427 Jumper Settings

AES3 & S/PDIF

OPTICAL

DISABLE

AES3

S/PDIF

DISABLE

ENABLE

DISABLE

Connects input as either AES3 or S/PDIF Connects input as OPTICAL AES3 INPUT enabled AES3 INPUT disabled S/PDIF INPUT enabled S/PDIF INPUT disabled

OPTICAL INPUT enabled OPTICAL INPUT disabled Connects output as AES3 XLR Connects output as S/PDIF coaxial S/PDIF OUTPUT enabled S/PDIF OUTPUT disabled

Enables MUTE when in hardware mode 1 Disables MUTE when in hardware mode 1

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