Lab 3 Details

Lab 3

• Develop a bio-feedback system based on a PWM (pulse width modulated) thermal sensor

• Use temperature setting to control the delays in an audio signal so that ‘stereo music’ seems to move across your head (left to right) in response to thermal changes

End of Lab. 2

Demonstration of bio-feedback operation using a ‘Mock’ temperature sensor

Build and test mock (fake) temperature device

Reminder of how to test a TTCOs task

Design the task state diagram

Develop Basic Test forFlashLED6 “working”

Write the code to satisfy the Tests

Defects• The number of syntax errors you did not see

IS A PROXY FOR

• The number of logical errors present in your code

• DO A PROPER CODE REVIEW

Don’t ignore ANY compiler warning messages

Why is a warning message such a big deal?

“crewOkay = true” is always true so ‘Customer release’ removes code

Back to Lab. 3

• If this works – then when you get your thermal sensor working (and writing into the global variable roomTemperature), then your bio-feedback device will operate

Handling key-presses and timing

Better solution?

• If there is no change in the Switch centre, then increment a counter each time the FlashRateLED5_SW3( ) is called

• More technical solution – read the clock cycle register (Assignment 1). However, does the increased accuracy (and increased coding time) actual give the customer a better solution

Displaying the temperature(Mock now, true later)

• Led5 and LED6 continue flashing when SW1 is released

Temperature sensor

• Task 1 – accurately determine the PWM values of the thermal sensor using input and place values in T1_Low and T2_High global variables

• Task 2 – Use T1_Low and T2_High global variables to calculate temperature

• Task 3 and 4 – Display temperature and do bio-feedback task

Design and test CalculateTemperature function BEFORE making TTCOS task

TMP03 Thermal sensor

Check that sensor still works

Low accuracy measurement of T1 and T2 (80% of Lab 3 complete)

Design part of Lab. 3 using General Purpose timer

Will need to read up in the Blackfin Processor Hardware Manual