EVAL-AD73322EB Datasheet, PDF (5/12 Pages) Analog Devices – EvaluationBoardforLowCost,LowPower, CMOSGerneralPurposeDualAnalogFrontEnd

EVAL-AD73322EB
DTMF (a:\EZ_73322\single\dtmf\dtmf.exe)
This program uses the DAC section of the CODEC to output a series of Dual-Tone Multi-Frequency (DTMF) tones
which are used in telephony applications. There are two possible settings for this demo
1 Generate a dial tone (the default setting) indicated by the LED on the EZKIT board being OFF
2 Generate a series of tones corresponding to a telephone number to be dialled indicated by the LED on the EZKIT
board being ON.
Use the pushbutton (S1) on the AD73322 eval board to toggle between the two options. To close the demo please push
the INTERRUPT button on the EZKIT board to return to the monitor program. This program processes output
samples at an 8 kHz ratewhich is set by the AD73322 sample rate setting in Control Register B.
File(s) used are: \EZ_73322\single\dtmf\dtmf.dsp
Build using: \EZ_73322\single\dtmf\dtmf.bat
ADPCM (a:\EZ_73322\single\adpcm\adpcm.exe)
This program demonstrates an Adaptive Differential Pulse Code Modulation (ADPCM) algorithm providing
compression to 32 kbits/sec. The AD73322 samples at an 8 kHz rate which determines the rate at which the ADPCM
algorithm runs. The program allows the input/output channel to be configured for loop-through at 8 kHz or for the
ADPCM algorithm to be run in a loop-through mode. The ADPCM algorithm takes the 16 bit ADC output and
compresses it to an 8 bit PCM value using µ-Law coding. The 8-bit PCM value is input to the ADPCM encoder which
generates a 4-bit output update value. In the loop-through, this 4-bit value is input to the ADPCM decoder whose 8-bit
output is further expanded from µ-Law to 16-bit linear coding.
There are two possible settings for this demo:
1 Loop-through of input to output at 8 kHz with no compression indicated by the LED on the EZKIT board being
OFF
2 Loop-through of input to output at 8 kHz featuring ADPCM indicated by the LED of the EZKIT board being
ON
Use the pushbutton (S1) on the AD73322 eval board to toggle between the two options. To close the demo please push
the INTERRUPT button on the EZKIT board to return to the monitor program. This program processes input and
output samples at an 8 kHz rate.
File(s) used are: \EZ_73322\single\adpcm\adpcms.dsp \EZ_73322\single\adpcm\Am_thr.dsp
\EZ_73322\single\adpcm\U_compre.dsp \EZ_73322\single\adpcm\U_expand.dsp
Build using: \EZ_73322\single\adpcm\adpcm.bat
AD73322 DUAL CODEC DEMO PROGRAMS
Stereo Emulation (a:\EZ_73322\dual\2in2out.exe)
This program configures a dual codec cascade to emulate a stereo codec in that one codec converts the right channel
while the other codec converts the left channel. This program’s code serves as a useful introduction to configuring the
AD73322 for cascaded operation.
File(s) used are: \EZ_73322\dual\2in2out.dsp
Build using: \EZ_73322\dual\dual.bat
Mixed Mode Stereo Emulation (a:\EZ_73322\dual\mm_mute.exe)
This program configures a dual codec cascade, in mixed mode, to emulate a stereo codec in that one codec converts the
right channel while the other codec converts the left channel. The mixed mode mode function allows the codecs to be
controlled while processing ADC and DAC samples. In this demo the pushbutton switch (S1) toggles the outputs
between MUTE OFF and MUTE ON. The red LED on the EZKIT LITE board is ON when MUTE is enabled.
File(s) used are: \EZ_73322\dual\mm_mute.dsp
Build using: \EZ_73322\dual\mix_mode.bat
AD73322 MULTI CODEC DEMO PROGRAMS
Three Channels (a:\EZ_73322\multi\3in3out.exe)
This program configures a three codec cascade.
File(s) used are: \EZ_73322\multi\3in3out.dsp
Build using: \EZ_73322\multi\make.bat
REV. A
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