电子定时器小项目 （基于STM32f103ZET6）中PA0的开始定时没有作用，但是PA3和PA4的按键有效
是长按吗 我弄的是长按一秒还是两秒开始计时
不知道你这个问题是否已经解决, 如果还没有解决的话:在led.c中的SR04初始化函数
void SR04_GPIO_Init(void)
{
GPIO_InitTypeDef GPIO_InitStructure;
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE);
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_Init(GPIOA, &GPIO_InitStructure);
GPIO_SetBits(GPIOA,GPIO_Pin_0);
}
led.h有关宏定义和声明
#define SR04 PAout(0) // PA0
void SR04_GPIO_Init(void);
经过初步分析，可能存在以下几种可能性：
1.硬件问题，PA0按键无法正常工作；
2.软件问题，PA0按键没有被正确初始化或中断处理有误导致无响应；
3.程序逻辑问题，PA0按键的相关代码出现了逻辑错误。
针对这些问题，可以采取以下解决方法：
1.检查PA0按键是否正常工作：使用万用表或示波器等工具测量PA0引脚的电压变化，观察按键是否能够正常接通和断开，确认PA0按键本身是否有问题。
2.检查软件代码：查看PA0引脚对应的GPIO口是否被正确初始化，确认是否已经打开了对应的中断，检查中断处理函数是否正确。如果发现有问题，需要针对问题逐步排查，修改代码。
3.检查程序逻辑：可能存在PA0按键相关的逻辑错误，例如输入的按键值判断错误，或者处理逻辑有误导致无响应。需要对PA0按键的相关代码进行仔细的分析和调试，查找逻辑错误并进行修正。
对于问题2和3，下面给出一份初步的代码示例，希望能够帮助您解决问题：
void TIM2_Configuration(void)
{
TIM_TimeBaseInitTypeDef TIM_InitStructure;
NVIC_InitTypeDef NVIC_InitStructure;
/* TIM2 clock enable */
RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM2, ENABLE);
/* Time base configuration */
TIM_InitStructure.TIM_Period = 999;
TIM_InitStructure.TIM_Prescaler = 71;
TIM_InitStructure.TIM_ClockDivision = TIM_CKD_DIV1;
TIM_InitStructure.TIM_CounterMode = TIM_CounterMode_Up;
TIM_TimeBaseInit(TIM2, &TIM_InitStructure);
/* TIM IT enable */
TIM_ITConfig(TIM2, TIM_IT_Update, ENABLE);
/* TIM2 enable counter */
TIM_Cmd(TIM2, ENABLE);
}
void GPIO_Configuration(void)
{
GPIO_InitTypeDef GPIO_InitStructure;
/* Enable GPIO clock */
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE);
/* Configure PA0, PA3 and PA4 as input floating */
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0 | GPIO_Pin_3 | GPIO_Pin_4;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;
GPIO_Init(GPIOA, &GPIO_InitStructure);
/* Configure EXTI Line */
GPIO_EXTILineConfig(GPIO_PortSourceGPIOA, GPIO_PinSource0);
GPIO_EXTILineConfig(GPIO_PortSourceGPIOA, GPIO_PinSource3);
GPIO_EXTILineConfig(GPIO_PortSourceGPIOA, GPIO_PinSource4);
/* Configure EXTI Line0, 3 and 4 */
EXTI_InitTypeDef EXTI_InitStructure;
EXTI_InitStructure.EXTI_Line = EXTI_Line0 | EXTI_Line3 | EXTI_Line4;
EXTI_InitStructure.EXTI_Mode = EXTI_Mode_Interrupt;
EXTI_InitStructure.EXTI_Trigger = EXTI_Trigger_Rising;
EXTI_InitStructure.EXTI_LineCmd = ENABLE;
EXTI_Init(&EXTI_InitStructure);
/* Enable and set EXTI Line0 Interrupt to the lowest priority */
NVIC_InitTypeDef NVIC_InitStructure;
NVIC_InitStructure.NVIC_IRQChannel = EXTI0_IRQn;
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 2;
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 2;
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
NVIC_Init(&NVIC_InitStructure);
/* Enable and set EXTI Line3 Interrupt to the lowest priority */
NVIC_InitStructure.NVIC_IRQChannel = EXTI3_IRQn;
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 2;
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 1;
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
NVIC_Init(&NVIC_InitStructure);
/* Enable and set EXTI Line4 Interrupt to the lowest priority */
NVIC_InitStructure.NVIC_IRQChannel = EXTI4_IRQn;
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 2;
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
NVIC_Init(&NVIC_InitStructure);
}
void EXTI0_IRQHandler(void)
{
if (EXTI_GetITStatus(EXTI_Line0) != RESET)
{
/* Deal with PA0 press event */
// Your code goes here
// ...
EXTI_ClearITPendingBit(EXTI_Line0);
}
}
void EXTI3_IRQHandler(void)
{
if (EXTI_GetITStatus(EXTI_Line3) != RESET)
{
/* Deal with PA3 press event */
// Your code goes here
// ...
EXTI_ClearITPendingBit(EXTI_Line3);
}
}
void EXTI4_IRQHandler(void)
{
if (EXTI_GetITStatus(EXTI_Line4) != RESET)
{
/* Deal with PA4 press event */
// Your code goes here
// ...
EXTI_ClearITPendingBit(EXTI_Line4);
}
}
int main(void)
{
/* Configure GPIO and TIM2 */
GPIO_Configuration();
TIM2_Configuration();
while (1)
{
/* Main loop */
// Your code goes here
// ...
}
}