Overview of Lab' 1

1
Over-view of Lab. 1

• For more details see the Lab. 1 web-site
• There will be a 20 min prelab quiz (based on
  Assignment 1 and 2) at the start of the lab.
  session so that you can demonstrate your
  preparedness for Lab. 0 Dont be late

2
Print out the Lab. 1 web-pages for use as
reference during the lab. period and during the
lab quiz Access to the web is not available.

• There will be a short 15-minute in-class quiz at
  the start of the lab. period dont be late
• Quiz will be based on knowledge demonstrated
  during assignments 1 and 2
• You may make use of YOUR printed notes and YOUR
  data books. Access to the web will not be
  available

3
Lab. 1

• We want to build a audio controller
• Audio in captured using audio A/D (CODEC)
• Audio out generated using audio D/A (CODEC)
• Manipulate the sound quality
• Push buttons to control audio controller
  operations
• LED lights to display operation results and sound
  volume level (dancing lights)

4
Lab. 1 Demonstration stream

• Your group must come into the laboratory class
  prepared to be able to demonstrate all of the
  following by the end of class period
• You will make use of some of the code developed
  during the assignments (Note assignments may be
  due AFTER the laboratory)
• Capture the audio signal and replay the signal
• Manipulate the audio signal
• Initialize the LED display interface (so that it
  works)
• Write a value to the LED display
• Read, and use, a value stored in the LED display
• Initialize the push-button controller interface
• Read, and use, a value provided by the
  push-button controller.
• Demonstrate tests to show that these operations
  work as required
• Understand, but not implement, how these
  operations can be used to provide the
  functionality of an audio controller.

5
Main Code pseudo code

• main( )
• Launch the Analog Devices audio echo program
  a background interrupt-driven task that is given
  to you you will modify this code
• InitializeLEDInterfaceASM( )
• InitializePFInterfaceASM( ) // Push-button
  controller
• Wait for button1 to be pressed and released
  (ReadButtonASM() ), then play the sound at
  half-volume.
• Wait for button2 to be pressed and released, play
  the sound at normal volume
• Each time button3 is pressed and released,
  transfer a known value from an array to the LED
  display (WriteLEDASM( ) ) and check that the
  expected value is displayed (ReadLEDASM( ) )
• Wait for button4 to be pressed and released, quit
  the program (turn off the sound and stop the
  processor)

6
Lab. 1 Application stream

• Everything that the demonstration stream
  completes
• In addition do it for real in real time
• Adjust the volume control dynamically
• On command -- make your favourite artist sound
  weird
• Generate the extremely fascinating (but
  completely useless) dancing lights which change
  with the audio stream volume level
• Have the opportunity to spend even more hours
  going for bonus marks to the laboratories where
  the volume control is done using a light sensor
  or

7
Task 1 Demonstration / Application
streamsDownload audio-talk-through program

• If you have not already done so, download and
  expand ENCM415Directory2006.zip file (used in
  assignment 1) so that you have the correct
  directory. structure and test driven development
  environment needed for Laboratory 1.
• Download and expand the files in
  06CPP_Talkthrough.zip into your Lab1 directory.
• Add the CPP_Talkthrough project in your Lab. 1
   directory to the VisualDSP environment --
  compile and link.
• Download the executable (.dxe) file onto the
  BF533 processor.
• Hook up your CD or IPOD output to the CJ2 stereo
  input.
• Hook up your ear-phones to the CJ3 stereo output.
  
• Run the CPP_Talkthrough.dxe executable and check
  that the talk through program is working.

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Task 2 -- Convert ProcessDataCPP( ) to
ProcessDataASM ( ) Both streams

• In talkthrough.h. add a prototype for your
  assembly code function Process_DataASM
• In ISR.cpp change to // call function that
  contains user codeif 0      Process_DataCPP() 
  // Use the C versionelse    
  Process_DataASM() // C assembly code routines
  especially developed for Lab. 1endif 
• Right-click on ProcessDataCPP.cpp entry. Use
  "FILE OPTIONS to exclude linking
• Use PROJECT clean project
• Add your ProcessDataASM.asm file to the project,
  recompile and link. Check that your code works
• More details on the Lab. 1 web pages

9
Task 3 Initialize the Programmable flag
interface 16 I/O lines on the Blackfin

• Warning could burn out the Blackfin processor
  if done incorrectly
• You need to set (store a known value to) a number
  of Blackfin internal registers
• Most important ones
• FIO_DIR Data DIRection 0 for input
• FIO_INEN INterface ENable
• FIO_FLAG_D Programmable FLAG Data register

10
Why do you need to know how to do read (load)
and write (store) on internal registers?

• Flag Direction register (FIO_DIR)
• Used to determine if the PF bit is to be used for
  input or output -- WARNING SMOKE POSSIBLE
  ISSUE
• Need to set pins PF11 to PF8 for input, leave all
  other pins unchanged

11
Registers used to control PF pins

• Flag Input Enable Register
• Only activate the pins you want to use (saves
  power in telecommunications situation)
• Need to activate pins PF11 to PF8 for input,
  leave all other pins unchanged

12
Registers used to control PF pins

• Flag Data register (FIO_FLAG_D)
• Used to read the PF bits (1 or 0)
• Need to read pins PF11 to PF8, ignore all other
  pins values

13
Task 3 Setting up the programmable flag
interface

• Follow the instructions carefully
• FIO_DIR direction register write 0s to all
  bits
• FIO_INEN input enable register write 1s to
  bits 8, 9, 10, 11
• Other registers set to 0
• There is a test program that will enable you to
  check your code provide a screen dump of test
  result.

14
Task 4 Read the switches on the front pannel

• Final laboratory requirements
• SW1 connected to PF8 -- Mute button (This task)
• SW2 connected to PF9 -- Gargle button (Task 5)
• SW3 connected to PF10 -- Volume up (Task 7)
• SW4 connected to PF11 -- Volume down (Task 7)
• Build Initialize_ProgrammableFlagsASM ( )
• MUST HAVE 50 pin cable connected between logic
  board and Blackfin
• Logic board power supply must be turned on

15
int ReadProgrammableFlags( )
16
Other tasks depend on the stream

• Demo-stream
• WAIT for button1 to be pressed and released
  (ReadButtonASM() ), then play the sound at
  half-volume.
• Wait for button2 to be pressed and released, play
  the sound at normal volume
• Application-stream
• WHILE button 1 is pressed add a mute operation
• WHILE button 2 is pressed add a gargle
  operation
• IF both pressed then mute operation
• After release of buttons (either order) normal
  operation

17
Gargling operation application stream

• Need to add a simple counter that increments by 1
  every 1/44000 s (each time that an audio sample
  is obtained)
• Use the counter to turn the sound off and on
  every ½ s
• Gargling sound is produced.
• You need to have a signed demo sheet from a 2nd
  or 4th year student. Bonus if the student is not
  from department

18
LED interface and Dancing Lights

• LED interface setup code provided
• Demo stream
• Transfer values from a known array to the LED
• Application stream
• Writing in C code (interfaced to your
  assembly code) display the amplitude (absolute
  value) of the sound will need to store 32
  values in an array and generate (running) average

19
Tests

• There will be software tests (E-TDD) to allow you
  to demonstrate that your code works correctly
• Note there are test codes available to test out
  your equipment
• This code can be used to test the switches and
  the LED interface on your board. SwitchToLED.dxe
• This is the final version of my code for Lab. 1.
   DrSmithLab1Final.dxe