Microchip Technology AC164129 Ficha De Dados

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PWM Speech Loopback Demo
© 2007 Microchip Technology Inc.
DS70297A-page 21
3.1.3
Loopback Application Software
The Loopback application on the accompanying CD uses the ADC and OCPWM 
drivers to read and output speech signals with the Audio PICtail Plus board. The 
application will loopback the microphone signal to the headphone output after 
performing a G.711 encode/decode operation on the microphone signal. Figure 3-2 is 
a flow chart of the demo application.
FIGURE 3-2:
APPLICATION FLOW CHART
START
Initialize ADC Driver
Initialize OCPWM Driver
Start ADC
Start OCPWM 
Input Frame
Available
?
G.711 µ-Law Encode
G.711 µ-Law Decode
OCPWM
Driver Busy
?
Write Frame
to OCPWM Driver
Yes
Yes
No
No