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#include "inc/hw_types.h"
#include "inc/hw_memmap.h"
#include "driverlib/sysctl.h"
#include "driverlib/gpio.h"
#include "driverlib/timer.h"
#include "driverlib/pin_map.h"
int main(void) {
unsigned long ulPeriod, dutyCycle;
// 40 MHz system clock
SysCtlClockSet(SYSCTL_SYSDIV_5|SYSCTL_USE_PLL|
SYSCTL_XTAL_16MHZ|SYSCTL_OSC_MAIN);
ulPeriod = 100000;
dutyCycle = 25000;
// Turn off LEDs
SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOF);
GPIOPinTypeGPIOOutput(GPIO_PORTF_BASE, GPIO_PIN_1|GPIO_PIN_2|GPIO_PIN_3);
GPIOPinWrite(GPIO_PORTF_BASE, GPIO_PIN_1|GPIO_PIN_2|GPIO_PIN_3, 0);
// Configure PB6 as T0CCP0
SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOB);
GPIOPinConfigure(GPIO_PB6_T0CCP0);
GPIOPinTypeTimer(GPIO_PORTB_BASE, GPIO_PIN_6);
// Configure timer
SysCtlPeripheralEnable(SYSCTL_PERIPH_TIMER0);
TimerConfigure(TIMER0_BASE, TIMER_CFG_SPLIT_PAIR|TIMER_CFG_A_PWM);
TimerLoadSet(TIMER0_BASE, TIMER_A, ulPeriod -1);
TimerMatchSet(TIMER0_BASE, TIMER_A, dutyCycle); // PWM
TimerEnable(TIMER0_BASE, TIMER_A);
while(1) { // The following code varies the duty cycle over time
TimerMatchSet(TIMER0_BASE, TIMER_A, dutyCycle++);
if(dutyCycle >= ulPeriod - 1)
dutyCycle = 0;
SysCtlDelay(50000);
}
}
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