Fan ControlFan Control

Nick SitarskiNick SitarskiVladi GergovVladi Gergov

ECE 473 Winter 2003ECE 473 Winter 2003Professor ShaoutProfessor Shaout

University Of Michigan-DearbornUniversity Of Michigan-Dearborn

ObjectivesObjectives

Create A RTOSCreate A RTOS Increase Fan Speed As Temperature Increase Fan Speed As Temperature

IncreasesIncreases Have Three ThreadsHave Three Threads

A/D ConversionA/D Conversion Print TemperaturePrint Temperature Check To Make Sure Temperature Is Not Check To Make Sure Temperature Is Not

To HighTo High Create Our Own SchedulerCreate Our Own Scheduler

CircuitryCircuitry

Temperature CalculationTemperature CalculationA/D Voltage VS Temperature In C

y = -40.8917Ln(x) + 81.994

10

20

30

40

50

60

70

1 2 3 4 5

A/D Voltage

Tem

per

atu

re I

n D

egre

es C

Dynamic Time SlicingDynamic Time Slicing

20,000 Cycles In One Complete Cycle20,000 Cycles In One Complete Cycle StartingStarting

10,000 Cycles For On-Time10,000 Cycles For On-Time 10,000 Cycles For Off-Time10,000 Cycles For Off-Time

As Temperature Increases On-Time Goes As Temperature Increases On-Time Goes UpUp

And Off-Time Goes DownAnd Off-Time Goes Down On-Time = (256-A/D)*30+10,000On-Time = (256-A/D)*30+10,000 Off-Time = 20,000 – On-TimeOff-Time = 20,000 – On-Time

ConclusionConclusion

All Objectives MetAll Objectives Met Scheduler Worked ProperlyScheduler Worked Properly Threads WorkedThreads Worked Temperature Within 1 Degree C Of Temperature Within 1 Degree C Of

ActualActual Questions?Questions?