void PWMInit(void)
{  												
   SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOF);
   SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOE);
   SysCtlPeripheralEnable(SYSCTL_PERIPH_PWM);
   SysCtlPWMClockSet(SYSCTL_PWMDIV_1);                                          // PWM时钟源1分频   80MHz
   PWMGenDisable(PWM_BASE,PWM_GEN_1);
   PWMGenDisable(PWM_BASE,PWM_GEN_2);
   //PWM2 PF2    PWM3  PF3
   GPIOPinTypePWM(GPIO_PORTF_BASE, GPIO_PIN_2);                                 // 硬件功能，2MA，弱上拉
   GPIOPinTypePWM(GPIO_PORTF_BASE, GPIO_PIN_3);
   GPIOPinConfigure(GPIO_PF2_PWM2);
   GPIOPinConfigure(GPIO_PF3_PWM3);
   //PWM4 PE0   PWM5  PE1
   GPIOPinTypePWM(GPIO_PORTE_BASE, GPIO_PIN_0);                                 // 硬件功能，2MA，弱上拉
   GPIOPinTypePWM(GPIO_PORTE_BASE, GPIO_PIN_1);
   GPIOPinConfigure(GPIO_PE0_PWM4);
   GPIOPinConfigure(GPIO_PE1_PWM5);

/****************************************************************************************************
                                 PWMGen1
*****************************************************************************************************/
   /*配置PWM*/
   PWMGenConfigure(PWM_BASE,PWM_GEN_1,PWM_GEN_MODE_SYNC
                                      |PWM_GEN_MODE_DOWN
                                      |PWM_GEN_MODE_GEN_SYNC_GLOBAL
                                      |PWM_GEN_MODE_FAULT_UNLATCHED
                                      |PWM_GEN_MODE_FAULT_LEGACY
                                      |PWM_GEN_MODE_FAULT_MINPER);
   
   HWREG(PWM_BASE+PWM_O_1_GENA)=0X008C;
   HWREG(PWM_BASE+PWM_O_1_GENB)=0X08C0;

   /*开启输出  PWMGen1*/
   PWMOutputState(PWM_BASE,PWM_OUT_2_BIT,true);
   PWMOutputState(PWM_BASE,PWM_OUT_3_BIT,true);
   PWMGenEnable(PWM_BASE,PWM_GEN_1);
  
/****************************************************************************************************
                                  PWMGen2
*****************************************************************************************************/
   /*配置PWM*/
   PWMGenConfigure(PWM_BASE,PWM_GEN_2,PWM_GEN_MODE_SYNC
                                      |PWM_GEN_MODE_DOWN
                                      |PWM_GEN_MODE_GEN_SYNC_GLOBAL
                                      |PWM_GEN_MODE_FAULT_UNLATCHED
                                      |PWM_GEN_MODE_FAULT_LEGACY
                                      |PWM_GEN_MODE_FAULT_MINPER);

   HWREG(PWM_BASE+PWM_O_2_GENA)=0X08C0;
   HWREG(PWM_BASE+PWM_O_2_GENB)=0X0C02;

   /*开启输出  PWMGen2*/
   PWMOutputState(PWM_BASE,PWM_OUT_4_BIT,true);
   PWMOutputState(PWM_BASE,PWM_OUT_5_BIT,true);
   PWMGenEnable(PWM_BASE,PWM_GEN_2);

   HWREG(PWM_BASE + PWM_O_1_LOAD)=CMPA_T_hht1;
   HWREG(PWM_BASE + PWM_O_1_CMPA)=CMPA_T_hht1*3/4;
   HWREG(PWM_BASE + PWM_O_1_CMPB)=CMPA_T_hht1*2/4;
  
   HWREG(PWM_BASE + PWM_O_2_LOAD)=CMPA_T_hht1;
   HWREG(PWM_BASE + PWM_O_2_CMPA)=CMPA_T_hht1*2/4;
   HWREG(PWM_BASE + PWM_O_2_CMPB)=CMPA_T_hht1*1/4;

   PWMSyncUpdate(PWM_BASE,PWM_GEN_1_BIT|PWM_GEN_2_BIT);
   PWMSyncTimeBase(PWM_BASE,PWM_GEN_1_BIT|PWM_GEN_2_BIT);
   
}