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ADSP-BF533 EZ-KIT Lite Internal Regulator Programming

Analog Devices, Inc.
DSP Division
Three Technology Way
Norwood, MA 02062

Date Created:	10/07/03

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This directory contains an example ADSP-BF533 project that shows how Programmable Flag pins (FIO),
Interrupts, and internal regulator can be configured in assembly. It also demonstrates the access to
the LEDs on the EZ-KIT Lite, which are connected to the on-board Flash.


Files contained in this directory:

VR_MODIFY_ASM.dpj			VisualDSP++ project file
main.asm					ASM file containing the main program 
Initialization.asm			ASM file containing all initialization routines
interrupts.asm				ASM file containing the interrupt service routines for FIO
readme.txt					this project description file
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CONTENTS

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


I.    FUNCTIONAL DESCRIPTION

This example demonstrates the initialization of the FIO pins, Interrupts, and the on-board Flash,
which allows access to the six LEDs on the EZ-KIT.  The program simply toggles one LED (LED9) based on
a "loaded core" loop.  Two switches on the EZ-KIT are used to modify the core voltage that the part
runs at based off the VR_CTL register.

SW4 will lower the core voltage and wrap to the max allowable Vcc if minimum is reached.
SW5 will raise the core voltage and wrap to the min allowable Vcc if maximum is reached.


II.   IMPLEMENTATION DESCRIPTION

The main file calls:

1. FIO setup
2. Flash setup
3. Interrupt configuration
4. Endless loaded core loop (toggling LED9) waiting for Flag interrupts (SW5)


III.  OPERATION DESCRIPTION

- Make sure that switch SW9 1-2 are turned on (connects SW4-PF8, SW5-PF9)
- Open the project "VR_MODIFY_ASM.dpj" in the VisualDSP Integrated Development Environment (IDDE).
- Under the "Project" menu, select "Build Project" (program is then loaded automatically into DSP).
- Select "Run" from the "Debug" menu.
- Observe LED9 toggling.
- Probe TP15 (just below and to the right of the hole in the center of the EZ-KIT), the voltage
  should read ~1.30V, the default Vcc.  When the SW4 button is pushed, the voltage reading goes
  down ~50mV.  For each push of SW4, the voltage drops ~50mV until the minimal voltage rating of
  ~0.75V is reached.  A subsequent push of SW4 results in a reading of ~1.30V, the max rating.
  
  Similarly, if the SW5 button is pushed, the reading will increment ~50mV until the maximum
  voltage rating of ~1.30V is reached, at which point a subsequent push of the SW5 button will
  result in a reading of ~0.75V, the min rating.  LED7 toggles with each push of either SW4 or
  SW5.  Also, when the core voltage crosses the 1V threshhold, the blinking frequency of LED9
  should visibly change (whether wrapping from high to low, low to high, or incrementing or
  decrementing across the 1V threshhold).