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ADSP21161 EZ-KIT Lite Taylor Series Sine Wave Tone Generation Demo

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

Date Created:	7/26/01

This directory contains example ADSP21161 subroutines that demonstrate the 
use of the ADSP21161 to generate an audio stream transmitted to the AD1836 
codec.

Files contained in this directory:

21161_EZKIT_Lite.ldf		Linker Description File
AD1836_ADT.dpj			Visual DSP++ 2.0 Project File
AD1836_reg_init_viaSPORTs.asm	Source for initializing AD1836 codec
AD1852_SPI_init.asm		Source for initializing AD1852 codec
Clear_SPT_regs.asm		Subroutines to clear SPORT1 registers
Init_21161_EZKit.asm		Source for main routine
ISR_table.asm			Interrupt Vector Table
Music.dat				Data file
Sinetbl.dat				Data file
SDRAM_initialization.asm	Initialize External Memory
SPORT02_TDM_Initialization.asm	Initialize SPORTS 0 & 2
SPT0_ISR_1836_Processing.asm	Interrupt Routine for SPT0
Talkthru.asm			Source for passing audio signal
WavMusic.asm			Source file for subroutine
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CONTENTS

I.	FUNCTION/ALGORITHM DESCRIPTION
II.	IMPLEMENTATION DESCRIPTION
III.	OPERATION DESCRIPTION       


I. FUNCTION/ALGORITHM DESCRIPTION

The basis of this project is the 21161 talkthrough example. A processing subroutine
is inserted into the Talkthrough routine.

II.   IMPLEMENTATION DESCRIPTION

AD1836/ADSP-21161N EZLAB  Music Demo Program                          
                                                                        
This routine generates a song using tones generated from a sine         
function approximation routine.                                         
                                                                        
The sin routine is implemented using 32-bit fixed-point math with the  	
Taylor Series Function Approximation.                                   
                                                                        
The song is then passed through an ADT (Automatic Double Tracking)      
digital delay effect, and then thickened with a slight chorus effect     
                                                                        
The audio data is sent out to the AD1836 Line Output Jack              


III.  OPERATION DESCRIPTION

- Plug in a microphone to Mic In and speakers to Ch 2 (Line Out)on the 21161 Ezkit Lite
- Open the project "AD1836_talkthru.dpj" in the VisualDSP++ Integrated Development Environment (IDE).
- Under the "Project" tab, select "Build Project".
- Open a ADSP21161 EZ-KIT Lite session in the VisualDSP++ Debugger.
- Load "Wavemusic.dxe"
- Run the Project and listen to the speakers and hear the generated effect.
- Use the IRQ 1 button to change the effect settings.

IV.  RUNTIME CONTROL PARAMETERS

- Hitting FLAG1 will bypass the post processing stereo chorus and digital delay routines.
- Hitting FLAG2 will bypass the digital delay effect
- Hitting FLAG3 will bypass the stereo chorus effect