MOTOROLA
DSPD56362EVM Upgrade Manual
3-1
SECTION 3
68HC11 SOURCE CODE DESCIPTION
3.1
INTRODUCTION
This section gives a brief description of how the 68HC11 microcontroller code works in case
the user needs to make modifications or additions to the user interface.
3.2
MAIN FUNCTION
The following steps are taken in the main function of the code:
1.
InitRegs( )-
Initialize 68HC11 control registers:
•
Configure Port A pins to be inputs from switches S2, S3, S4, and S5.
•
Configure Port B pins to be outputs to LCD and D/A converters control signals.
•
Configure Port C pins to be outputs to LCD data lines.
•
Configure Port D pins to be input from and outputs to DSP’s SHI port.
2.
InitVol( )-
Initialize D/A converters:
•
Configure D/A converters to operate in software mode.
•
Initialize attenuation and input data format for all four D/A converters.
3.
InitKey( )-
Initialize key input manager:
•
Configure keypad action on the EVM.
4.
InitLCD( )-
Initialize LCD manager:
•
Configure to display messages on the LCD.
5.
InitParams( )-
Initialize parameters:
•
Initialize left, right, center, surround, and subwoofer volume at 0 dB.
6.
SetMode(BOOT_MODE)
- Display initial screen on LCD.
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Freescale Semiconductor, Inc.
For More Information On This Product,
Go to: www.freescale.com
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