pwm out

main.c

@@ -16,6 +16,12 @@
 #include "Crystalfontz128x128_ST7735.h"
 #include <stdio.h>
 #include "buttons.h"
+#include <math.h>
+#include "inc/hw_memmap.h"
+#include "driverlib/gpio.h"
+#include "driverlib/pwm.h"
+#include "driverlib/pin_map.h"
+#define PWM_FREQUENCY 20000 // PWM frequency = 20 kHz
 
 uint32_t gSystemClock; // [Hz] system clock frequency
 volatile uint32_t gTime = 0; // time in hundredths of a second
@@ -24,6 +30,25 @@ int main(void)
 {
     IntMasterDisable();
 
+    // configure M0PWM2, at GPIO PF2, BoosterPack 1 header C1 pin 2
+    SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOF);
+    GPIOPinTypePWM(GPIO_PORTF_BASE, GPIO_PIN_2);
+    GPIOPinConfigure(GPIO_PF2_M0PWM2);
+    GPIOPadConfigSet(GPIO_PORTF_BASE, GPIO_PIN_2,
+    GPIO_STRENGTH_2MA, GPIO_PIN_TYPE_STD);
+    // configure the PWM0 peripheral, gen 1, outputs 2 and 3
+    SysCtlPeripheralEnable(SYSCTL_PERIPH_PWM0);
+    // use system clock without division
+    PWMClockSet(PWM0_BASE, PWM_SYSCLK_DIV_1);
+    PWMGenConfigure(PWM0_BASE, PWM_GEN_1,
+    PWM_GEN_MODE_DOWN | PWM_GEN_MODE_NO_SYNC);
+    PWMGenPeriodSet(PWM0_BASE, PWM_GEN_1, roundf((float)gSystemClock/PWM_FREQUENCY));
+    PWMPulseWidthSet(PWM0_BASE, PWM_OUT_2,
+    roundf((float)gSystemClock/PWM_FREQUENCY*0.4f));
+    PWMOutputState(PWM0_BASE, PWM_OUT_2_BIT, true);
+    PWMGenEnable(PWM0_BASE, PWM_GEN_1);
+
+
     // Enable the Floating Point Unit, and permit ISRs to use it
     FPUEnable();
     FPULazyStackingEnable();