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/*******************************************************************************
* 函 数 名 : My_EXTI_Init
* 函数功能 : 外部中断初始化
* 输 入 : 无
* 输 出 : 无
*******************************************************************************/
void My_EXTI_Init(void)
{
NVIC_InitTypeDef NVIC_InitStructure;
EXTI_InitTypeDef EXTI_InitStructure;
RCC_APB2PeriphClockCmd(RCC_APB2Periph_SYSCFG,ENABLE);
SYSCFG_EXTILineConfig(EXTI_PortSourceGPIOA,EXTI_PinSource0);
SYSCFG_EXTILineConfig(EXTI_PortSourceGPIOE,EXTI_PinSource2);
SYSCFG_EXTILineConfig(EXTI_PortSourceGPIOE,EXTI_PinSource3);
SYSCFG_EXTILineConfig(EXTI_PortSourceGPIOE,EXTI_PinSource4);
//EXTI0 NVIC 配置
NVIC_InitStructure.NVIC_IRQChannel = EXTI0_IRQn;//EXTI0中断通道
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority=2;//抢占优先级
NVIC_InitStructure.NVIC_IRQChannelSubPriority =3; //子优先级
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE; //IRQ通道使能
NVIC_Init(&NVIC_InitStructure); //根据指定的参数初始化VIC寄存器
//EXTI2 NVIC 配置
NVIC_InitStructure.NVIC_IRQChannel = EXTI2_IRQn;//EXTI2中断通道
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority=2;//抢占优先级
NVIC_InitStructure.NVIC_IRQChannelSubPriority =2; //子优先级
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE; //IRQ通道使能
NVIC_Init(&NVIC_InitStructure); //根据指定的参数初始化VIC寄存器
//EXTI3 NVIC 配置
NVIC_InitStructure.NVIC_IRQChannel = EXTI3_IRQn;//EXTI3中断通道
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority=2;//抢占优先级
NVIC_InitStructure.NVIC_IRQChannelSubPriority =1; //子优先级
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE; //IRQ通道使能
NVIC_Init(&NVIC_InitStructure); //根据指定的参数初始化VIC寄存器
//EXTI4 NVIC 配置
NVIC_InitStructure.NVIC_IRQChannel = EXTI4_IRQn;//EXTI4中断通道
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority=2;//抢占优先级
NVIC_InitStructure.NVIC_IRQChannelSubPriority =0; //子优先级
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE; //IRQ通道使能
NVIC_Init(&NVIC_InitStructure); //根据指定的参数初始化VIC寄存器
EXTI_InitStructure.EXTI_Line=EXTI_Line0;
EXTI_InitStructure.EXTI_Mode=EXTI_Mode_Interrupt;
EXTI_InitStructure.EXTI_Trigger=EXTI_Trigger_Rising;
EXTI_InitStructure.EXTI_LineCmd=ENABLE;
EXTI_Init(&EXTI_InitStructure);
EXTI_InitStructure.EXTI_Line=EXTI_Line2|EXTI_Line3|EXTI_Line4;
EXTI_InitStructure.EXTI_Mode=EXTI_Mode_Interrupt;
EXTI_InitStructure.EXTI_Trigger=EXTI_Trigger_Falling;
EXTI_InitStructure.EXTI_LineCmd=ENABLE;
EXTI_Init(&EXTI_InitStructure);
}
例程中,PA0与IRQ0是联系在一起的,但是我发现,程序中没有单独的一条语句指定了PA0和IRQ0之间的关系。
我认为之所以PA0与IRQ0是联系在一起的,完全取决于语句出现的先后顺序,
比如:
SYSCFG_EXTILineConfig(EXTI_PortSourceGPIOA,EXTI_PinSource0);是第一个出现
NVIC_InitStructure.NVIC_IRQChannel = EXTI0_IRQn;也是第一个出现
所以PA0与IRQ0是联系在一起的。
请问是这样吗?
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