void Counter_Config()

{

NVIC_InitTypeDef NVIC_InitStructure;

GPIO_InitTypeDef GPIO_InitStructure;

TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;

RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM4, ENABLE);

RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB, ENABLE);

GPIO_InitStructure.GPIO_Pin = GPIO_Pin_7;

GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;

GPIO_InitStructure.GPIO_Speed = GPIO_Speed_2MHz;

GPIO_Init(GPIOB, &GPIO_InitStructure);

//TIM4輸出初始化

TIM_DeInit(TIM4);

TIM_TimeBaseStructure.TIM_Period = 100; //計數(shù)值=100-1

TIM_TimeBaseStructure.TIM_Prescaler = 0; //預分頻

TIM_TimeBaseStructure.TIM_ClockDivision = TIM_CKD_DIV1; //時鐘分割

TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Down; //模式

TIM_TimeBaseInit(TIM4, &TIM_TimeBaseStructure); //基本初始化

TIM_SetCounter(TIM4, 100); //設置 TIM4 計數(shù)器寄存器值//設置 TIMx 自動重裝載寄存器值

TIM_ARRPreloadConfig(TIM4, ENABLE);

TIM_SelectInputTrigger(TIM4, TIM_TS_TI2FP2); //若為通道1 ，則為TIM_TS_TI1FP1

TIM_SelectSlaveMode(TIM4,TIM_SlaveMode_External1);

TIM_SetCompare2(TIM4, 100);

TIM_SetComper1(TIM4,100);TIM_Cmd(TIM4, ENABLE); //啟動TIM4TIM_ClearFlag(TIM4, TIM_IT_CC2);

TIM_ITConfig(TIM4, TIM_IT_CC2, ENABLE)//中斷配置

NVIC_InitStructure.NVIC_IRQChannel =TIM4_IRQChannel;

NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 3; //搶占優(yōu)先級0NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0; //響應優(yōu)先級0NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE; //允許中斷

NVIC_Init(&NVIC_InitStructure); //寫入設置

}

void TIM4_IRQHandler(void)

{

TIM_ClearFlag(TIM4, TIM_IT_CC2);

XX++;

}