HW$7\_$C$\_$PWM$\_$PRG$\_$A: PWM C Programming Assignment A

In this assignment we program the TAOCCR$1$ PWM output to control the brightness of an LED.

Hardware specification:

Connect the TA$0-$OUT$1($P$2\mathrm{.}4)$ to the Anode of an LED $($Anode is the longer leg of the LED$).$

Connect other leg of LED to a resistor $($between $330$ and $500).$

The other side of resistor must be connected to the GND$.$

Software specifications:

Use Up$-$Mode to generate PWM with:

Period $=64000$

Divider $=1$

Duty $=0000$

CLK $=$ SMCLK

PWM Mode: Toggle set

Assignment: Write a C program that turns the LED ON with variable PWM Duty Cycle. The Duty Cycle starts from $00$ and increases $12\mathrm{.}5\%$ every $0\mathrm{.}5sec.$

Report:

Archive your project files and upload it $($zip file$)$ in Canvas.

Your code must come with comments so that the purpose of each line must be explained.

Copy your source code in a word file and upload it in Canvas including the answer to the following questions:

a$.$ Find the period of output signal $($PWM$).$

b$.$ Write the equations that you use to calculate the duty cycle and explain how you change it$.$

c$.$ Find the maximum divider that the LED light is still continuous and does not blink.

$/*$ DriverLib Includes Standard Includes Define Statements Function Includes Halting the Watchdog $*/$

MAP$\_$WDT$\_$A$\_$holdTimer$()$;

MAP$\_$GPIO$\_$setAsOutputPin$($GPIO$\_$PORT$\_$P$2,$ GPIO$\_$PIN$4)$; $//$ Configures the LED

port $2\mathrm{.}4$ to be enabled

ConfigPWMTimer$($PERIOD$,$ CLOCKDIVIDER, $0)$;

MAP$\_$Timer$\_$A$\_$startCounter$($TIMER$\_$AO$\_$BASE, TIMER$\_$A$\_$UP$\_$MODE$)$ ;

enable$\_$interrupts$()$;

delay$\_$cycles$(3000000)$;

uint$16\_$t duty $=0$;

while$(1)\{$

$\_\_$delay$\_$cycles$(500000)$;

MAP$\_$GPIO$\_$setoutputHighonPin$($GPIO$\_$PORT$\_$P$2,$ GPIO$\_$PIN$4)$;

duty $+\frac{?}{b}=ar(8)000$;

if $($duty $>$ PERIOD$)$

duty $=$ PERIOD;

timerPWMConfig.dutyCycle $=$ duty; $//$ Update duty cycle

MAP$\_$Timer$\_$A$\_$generatePWM $($TIMER$\_$AO$\_$BASE, &timerPWMConfig$)$; $//$ Update

PWIM

$\}$

$\}$

$//$ TIMER PWM $!!$

void configPWMTimer$($uint$16\_$t clockPeriod, uint$16\_$t clockDivider, uint$16\_$t

duty$)\{$

const uint$32\_$t TIMER$=$TIMER$\_$AO$\_$BASE;

uint$16\_$t dutyCycle $=$ duty$*$clockPeriod$/100$;

timerPWMConfig.clockSource $=$ TIMER$\_$A$\_$CLOCKSOURCE$\_$SMCLK;

timerPWMConfig.clockSourceDivider $=$ clockDivider;

timerPWMConfig.timerPeriod $=$ clockPeriod;

timerPWMConfig.compareOutputMode $=$ TIMER$\_$A$\_$OUTPUTMODE$\_$TOGGLE$\_$SET;

timerPWMConfig.compareRegister $=$ TIMER$\_$A$\_$CAPTURECOMPARE$\_$REGISTER$\_1$;

timerPWMConfig.dutyCycle $=$ dutyCycle;

MAP Timer A generatePWM$($TIMER$,$ &timerPWMConfig$)$;

Can you please help with this problem? The code i have currently can only turn on the LED but never increment it$.$ Apologies if its not much help but i am greatly confused with how all this goes.