1. Introduction to Test Driven Development
Building tests and code for a “software radio”

2. Concepts of TDD, M. Smith, ECE, University of Calgary, Canada
Stages in a conventional radio
Stages in a software radio
Goals for the “long term” project
Concept of test driven development
Digital rectification
Tests for integer array rectification
Tests for float array rectification (C++ compiler)
Tests for rectification in assembly code
More details of test driven development
11/20/2018
Concepts of TDD, M. Smith, ECE, University of Calgary, Canada

3. Conventional “AM” radio
RF STAGE
Antenna
Pickup
AUDIO STAGE
Low pass Filter + amplifier
Low pass Filter
Rectifier
Mixer
Local Oscillator
IF STAGE
Audio out
11/20/2018
Concepts of TDD, M. Smith, ECE, University of Calgary, Canada

4. Software “AM” radio concept
RF STAGE
Antenna
Pickup
AUDIO STAGE
Low pass Filter + amplifier
Low pass Filter
Rectifier
Mixer
Local Oscillator
IF STAGE
Audio out
Most stages handled with high speed software
11/20/2018
Concepts of TDD, M. Smith, ECE, University of Calgary, Canada

5. Software “FM” radio concept
RF STAGE
AUDIO STAGE
Antenna
Pickup
Low pass Filter + amplifier
What ever is needed
Rectifier
Audio out
Most stages handled with high speed software
11/20/2018
Concepts of TDD, M. Smith, ECE, University of Calgary, Canada

6. Concepts of TDD, M. Smith, ECE, University of Calgary, Canada
Real “software” radio
Looking at RF stage to bring in wireless signal
Software radio is the rest of it
Update communication protocols
Change noise suppression characteristics “on the fly”
Etc.
Excellent topic for individual presentation (8 minute talk – 10 slides max – at the end of term) or possible joint presentation (16 minute talk – 20 slides max)
11/20/2018
Concepts of TDD, M. Smith, ECE, University of Calgary, Canada

7. Rectification algorithm
Choices are
C++ compiler in DEBUG mode
int *RectifyDEBUG(int initial[ ], int final, int N);
float *RectifyDEBUG (float initial[ ], float final, int N);
C++ compiler in RELEASE mode
int *RectifyRELEASE(int initial[ ], int final, int N);
float *RectifyRELEASE(float initial[ ], float final, int N);
“US” in ASSEMBLY mode
int *RectifyASM(int initial[ ], int final, int N);
float *RectifyASM(float initial[ ], float final, int N);
“US” in OPTIMIZED ASSEMBLY mode
int *RectifyOPTASM (int initial[ ], int final, int N);
float *RectifyOPTASM (float initial[ ], float final, int N);
11/20/2018
Concepts of TDD, M. Smith, ECE, University of Calgary, Canada

8. Expected relative advantages
Compiler debug mode
Compiler release (optimized) mode
“US” – assembly mode
“US” – optimized assembly mode
11/20/2018
Concepts of TDD, M. Smith, ECE, University of Calgary, Canada

9. Standard testing practice
Heavy on documentation
TLD
Test Last Development
11/20/2018
Concepts of TDD, M. Smith, ECE, University of Calgary, Canada

10. Test Driven Development
Customer Tests – personally find these hard to do
Not clear if there is yet “a real process available”
Developer Tests – have found many advantages
CUSTOMER
DEVELOPER
11/20/2018
Concepts of TDD, M. Smith, ECE, University of Calgary, Canada

11. Lets apply TDD to rectification issue
Overall technique
Decide on a particular test action
Write the test(s)
Write the simplest possible code to satisfy the test(s)
“Refactor” the code to improve “quality”
Definition of “quality” is unclear in the literature
Ease of “use” or “reuse” of code
Reliable to use – “robust”
My additional idea – meets speed requirements for the embedded situation
TDD in an embedded / ubiquitous computing environment is a major part of my current research with funding from NSERC and Analog Devices
11/20/2018
Concepts of TDD, M. Smith, ECE, University of Calgary, Canada

12. Concepts of TDD, M. Smith, ECE, University of Calgary, Canada
First unit test
Can I link to a particular test file and activate the tests within that files?
This include file provides all the macros needed for the TDD environment
Simple test to indicate the test set being run. Also indicates that a link is possible
11/20/2018
Concepts of TDD, M. Smith, ECE, University of Calgary, Canada

13. First unit test
Can I link to a particular test file and activate the tests within that files?
Test control. Certain tests always need to be run (totally automated). Others are more difficult to automate
This include file provides defines needed for the project
11/20/2018
Concepts of TDD, M. Smith, ECE, University of Calgary, Canada

14. Concepts of TDD, M. Smith, ECE, University of Calgary, Canada
First unit test
Can I link to a particular test file and activate the tests within that files?
NOTE: REQUIREMENT – CUSTOMER TEST CODE MUST BE AVAILABLE TO DEVELOPER (Does not mean customer might not have other test code
11/20/2018
Concepts of TDD, M. Smith, ECE, University of Calgary, Canada

15. Concepts of TDD, M. Smith, ECE, University of Calgary, Canada
Running the tests
Need a fast – easy to use – way of switching between running the tests, and demonstrating the working customer product
11/20/2018
Concepts of TDD, M. Smith, ECE, University of Calgary, Canada

16. Running the customer product code
11/20/2018
Concepts of TDD, M. Smith, ECE, University of Calgary, Canada

17. Test code – Report Mode Report all tests. Success and failures
Report successes only
11/20/2018
Concepts of TDD, M. Smith, ECE, University of Calgary, Canada

18. Test code – test level control
11/20/2018
Concepts of TDD, M. Smith, ECE, University of Calgary, Canada

19. Result of “link test” Disassembler window
Source or “Mixed mode” window
Project window
Editor tabs selected
Twin processors can be controlled
Results in VisualDSP CONSOLE WINDOW
11/20/2018
Concepts of TDD, M. Smith, ECE, University of Calgary, Canada

20. Obvious test – actually contained a hidden bug
11/20/2018
Concepts of TDD, M. Smith, ECE, University of Calgary, Canada

21. Integer array tests ZERO-LENGTH ARRAY
Unspecified requirement – shown as part of test functionality
Function return pointer = NULL if error condition present
11/20/2018
Concepts of TDD, M. Smith, ECE, University of Calgary, Canada

22. Concepts of TDD, M. Smith, ECE, University of Calgary, Canada
Float tests
You write the required tests for testing rectification of floating point arrays
Test for correct zero-length error response
Test for correct rectification operation
11/20/2018
Concepts of TDD, M. Smith, ECE, University of Calgary, Canada

23. Concepts of TDD, M. Smith, ECE, University of Calgary, Canada
Zero-length test
Modify the integer test case
11/20/2018
Concepts of TDD, M. Smith, ECE, University of Calgary, Canada

24. Float rectification test
11/20/2018
Concepts of TDD, M. Smith, ECE, University of Calgary, Canada

25. Take notes from the screen
11/20/2018
Concepts of TDD, M. Smith, ECE, University of Calgary, Canada

26. Speed tests – integer code versions
11/20/2018
Concepts of TDD, M. Smith, ECE, University of Calgary, Canada

27. Using the tests – practical approach
Just because all the tests are known, does not mean that you use all of them immediately
If you use all of them immediately, you get a lot of failure messages, which is very soul destroying
I bring first test in – write the code to satisfy that test
Keep track of “defects” and “errors” as QA
Bring second test in – write the code to satisfy that test
Run all available tests to make sure nothing “broke”
Bring third test in – write the code to satisfy that test
11/20/2018
Concepts of TDD, M. Smith, ECE, University of Calgary, Canada

28. Concepts of TDD, M. Smith, ECE, University of Calgary, Canada
Concepts covered
Stages in a conventional radio
Stages in a software radio
Goals for the “long term” project
Concept of test driven development
Digital rectification
Tests for integer array rectification
Tests for float array rectification (C++ compiler)
Tests for rectification in assembly code
More details of test driven development
11/20/2018
Concepts of TDD, M. Smith, ECE, University of Calgary, Canada