STM32定时器溢出模式计时设置

主机:WIN7

开发环境:MDK4.23

MCU:STM32F103CBT6

源代码1:

说明:定时器采用TIM2,时钟源为内部8M晶振,向上溢出模式.此定时器用在延时函数,最小可以延时1us,故没有采用中断形式定时.

初始化代码:

RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM2,ENABLE);//重新将Timer设置为缺省值TIM_DeInit(TIM2);//采用内部时钟给TIM2提供时钟源TIM_InternalClockConfig(TIM2);timInitStruct.TIM_ClockDivision = TIM_CKD_DIV2;   			//定时器基准频率8MHztimInitStruct.TIM_Prescaler = 8 - 1;           				//计数频率为1us跳转1次timInitStruct.TIM_CounterMode = TIM_CounterMode_Up; 		//向上计数timInitStruct.TIM_RepetitionCounter = 0;timInitStruct.TIM_Period = 0; 								//这个值实际上就是TIMX->ARR，延时开始时重新设定即可TIM_TimeBaseInit(TIM2, &timInitStruct);TIM_ITConfig(TIM2, TIM_IT_Update, ENABLE); 					//计数溢出时触发中断TIM_Cmd(TIM2, ENABLE);				 						//开启计数器

//延时1us//最大65536usvoid _delay_us(uint16_t t){TIM_SetCounter(TIM2,0);TIM_SetAutoreload(TIM2,t - 1);//等待时间到while (TIM_GetITStatus(TIM2,TIM_FLAG_Update) == 0);//停止计数TIM_SetAutoreload(TIM2,0);//清中断标志TIM_ClearITPendingBit(TIM2,TIM_FLAG_Update);}//延迟1ms//最大65msvoid _delay_ms(uint8_t t){if (t > 65){t = 65;}_delay_us(t * 1000);}

源代码2:

说明:定时器采用TIM3,时钟源为内部8M晶振,向上溢出模式.此定时器用在长时间计时,最小计时间隔为100us,故采用中断形式定时.

初始化代码:

//中断NVIC设置：允许中断，设置优先级NVIC_PriorityGroupConfig(NVIC_PriorityGroup_1);NVIC_InitStructure.NVIC_IRQChannel = TIM3_IRQn;    			//更新事件NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;   //抢占优先级0NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;          //响应优先级1NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;             //允许中断NVIC_Init(&NVIC_InitStructure);                             //写入设置RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM3,ENABLE);//重新将Timer设置为缺省值TIM_DeInit(TIM3);//采用内部时钟给TIM3提供时钟源TIM_InternalClockConfig(TIM3);timInitStruct.TIM_ClockDivision = TIM_CKD_DIV2;   			//定时器基准频率8MHztimInitStruct.TIM_Prescaler = 800 - 1;           			//计数频率为100us跳转1次timInitStruct.TIM_CounterMode = TIM_CounterMode_Up; 		//向上计数timInitStruct.TIM_RepetitionCounter = 0;timInitStruct.TIM_Period = 0; 								//这个值实际上就是TIMX->ARR，延时开始时重新设定即可TIM_TimeBaseInit(TIM3, &timInitStruct);//清溢出中断标志TIM_ClearFlag(TIM3, TIM_FLAG_Update);//禁止ARR预装载缓冲器TIM_ARRPreloadConfig(TIM3, DISABLE);//开启中断TIM_ITConfig(TIM3, TIM_IT_Update, ENABLE); 				TIM_Cmd(TIM3, ENABLE);				 						//开启计数器

//TIM3中断void TIM3_IRQHandler(void){if(TIM_GetITStatus(TIM3, TIM_IT_Update) == SET){TIM3->ARR = 0;//清中断溢出标志TIM_ClearITPendingBit(TIM3,TIM_FLAG_Update);//发送信号Sig_Table.stop_require = 1;}}