readme.txt

BF533 与音频解码器连接回放代码

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ADSP-BF533 EZ-KIT Lite ASM Based AD1836 TALKTHRU

Analog Devices, Inc.
DSP Division
Three Technology Way
P.O. Box 9106
Norwood, MA 02062

Date Created:	04/03/03

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This directory contains an example ADSP-BF533 subroutine that demonstrates the 
initialization of the link between SPORT0 on the ADSP-BF533 and the AD1836 
stereo Codec.  This is done by initializing the link in I2S mode and implementing 
a simple talk-through routine.  

Files contained in this directory:

readme.txt					this file
main.asm					ASM file containing the main program and variable declaration
Initialize.asm				ASM file containing all initialization routines
interrupts.asm				ASM file containing the interrupt service routine for 
							SPORT0_RX
Process_data.asm			ASM file for processing incoming data
Talkthrough.h				ASM header file containing define sections
startup.asm					Generic Startup file
startup.h					header file which contains #define found in startup.asm
ASM_Talkthrough_I2S.dpj		VisualDSP++  project file
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CONTENTS

I.		FUNCTIONAL DESCRIPTION
II.		IMPLEMENTATION DESCRIPTION
III.	OPERATION DESCRIPTION


I.    FUNCTIONAL DESCRIPTION

The Talkthru demo demonstrates the initialization of SPORT0 to establish a link 
between the ADSP-BF533 and the AD1836 Codec.
 
The program simply sets up the SPI port to configure the AD1836 codec in I2S mode.
SPORT0 is then setup to receive/transmit audio samples from the AD1836.  Audio
samples received from the AD1836 are moved into the DSP's receive buffer, using 
DMA.  The samples are processed by the ADSP-BF533 and place in the transmit buffer.
In turn, the transmit buffer is used to transmit data to the AD1836.  This results
in a simple talk-through where data is moved in and out of the DSP with out 
performing any computations on the data.


II.   IMPLEMENTATION DESCRIPTION

The Initialization module initializes:

1. EBIU setup 
2. Flash setup
3. SPI setup to initialize AD1836 codec
4. SPORT0 setup
5. DMA setup
6. Interrupt configuration


III.  OPERATION DESCRIPTION

- Open the project "ASM_Talkthrough_I2S.dpj" in the VisualDSP Integrated Development
	Environment (IDDE).
- Under the "Project" menu, select "Build Project" (program is then loaded 
	automatically into DSP).
- Turn pin 5 and 6 of SW9 on the AD-BF533 EZ-KIT Lite ON, these will connect 
	RSCLK0 -> TSCLK0 and RFS0 -> TFS0.  
- Setup an input source (such as a radio) to the audio in jack and an output 
	source (such as headphones) to the audio out jack of the EZ-KIT Lite.  See the
	ADSP-BF533 EZ-KIT Lite User's Manual for more information on setting up the
	hardware.
- Select "Run" from the "Debug" menu of VisualDSP.
- Listen to the operation of the talk-through