3200 控制 pwm

1、参考TI的PWM例程，将PWM的信号输出。

2、通过定时器更新PWM的占空比只需要在程序中更新比较值，具体代码如下：

void UpdateDutyCycle(unsigned long ulBase, unsigned long ulTimer,unsigned char ucLevel)
{
//
// Match value is updated to reflect the new dutycycle settings
//
MAP_TimerMatchSet(ulBase,ulTimer,(ucLevel*DUTYCYCLE_GRANULARITY));
}

// RYB - Update the duty cycle of the corresponding timers.
// This changes the brightness of the LEDs appropriately.
// The timers used are as per LP schematics.
// 改变占空比！
for(iLoopCnt = 0; iLoopCnt < 255; iLoopCnt++)
{
UpdateDutyCycle(TIMERA2_BASE, TIMER_B, iLoopCnt);
UpdateDutyCycle(TIMERA3_BASE, TIMER_B, iLoopCnt);
UpdateDutyCycle(TIMERA3_BASE, TIMER_A, iLoopCnt);
MAP_UtilsDelay(100000);
}