3.22 ARM day7

实现三个按键的中断，现象和代码

include/key_inc.h：

#ifndef __KEY_INC_H__
#define __KEY_INC_H__
#include "stm32mp1xx_gic.h"
#include "stm32mp1xx_exti.h"
#include "stm32mp1xx_rcc.h"
#include "stm32mp1xx_gpio.h"
void key1_it_config();
void key2_it_config();
void key3_it_config();
#endif

src/key_inc.c：

 #include"key_inc.h"
 
 void key1_it_config()
 {
    //使能GPIOF外设时钟
    RCC->MP_AHB4ENSETR |= (0x1<<5);
    //将PF9设置为输入模式
    GPIOF->MODER &= (~(0x3<<18));
    //设置由PF9管脚产生EXTI9事件
    EXTI->EXTICR3 &= (~(0XFF<<8));
    EXTI->EXTICR3 |= (0X05<<8);
    //通过下降沿检测EXTI9事件是否产生
    EXTI->FTSR1 |= (0x1<<9);
    //取消EXTI9中断屏蔽
    EXTI->C1IMR1 |= (0x1<<9);
    //设置EXTI9中断全局使能
    GICD->ISENABLER[3] |= (0x1<<3);
    //设置中断优先级
    GICD->IPRIORITYR[24] &= (~(0x1f<<27));
      //设置CPU0处理当前中断
    GICD->ITARGETSR[24] |= (0x1<<24);
    //设置组0中断可以被转发到GICC层
    GICD->CTRL |=0X1;
    //设置中断优先级掩码
    GICC->PMR |= (0x1f<<3);
    //设置组0中断交给指定处理器处理
    GICC->CTRL |= 0x1;
 }
  void key2_it_config()
 {
    //使能GPIOF外设时钟
    RCC->MP_AHB4ENSETR |= (0x1<<5);
    //将PF7设置为输入模式
    GPIOF->MODER &= (~(0x3<<14));
    //设置由PF9管脚产生EXTI9事件
    //设置由PF7管脚产生EXTI7事件
    EXTI->EXTICR2 &= (~(0XFF<<24));
    EXTI->EXTICR2|= (0X05<<24);
    //通过下降沿检测EXTI7事件是否产生
    EXTI->FTSR1 |= (0x1<<7);
    //取消EXTI7中断屏蔽
    EXTI->C1IMR1 |= (0x1<<7);
    //设置EXTI7中断全局使能
    GICD->ISENABLER[3] |= (0x1<<1);
    //设置中断优先级
    GICD->IPRIORITYR[24] &= (~(0x1f<<11));
    //设置CPU0处理当前中断
    GICD->ITARGETSR[24] &=( ~(0x3<<8));
    GICD->ITARGETSR[24] |= (0x1<<8);
    //设置组0中断可以被转发到GICC层
    GICD->CTRL |=0X1;
    //设置中断优先级掩码
    //GICC->PMR |= (0x1f<<3);
    //设置组0中断交给指定处理器处理
    //GICC->CTRL |= 0x1;
 }
 
   void key3_it_config()
 {
    //使能GPIOF外设时钟
    RCC->MP_AHB4ENSETR |= (0x1<<5);
    //将PF7设置为输入模式
    GPIOF->MODER &= (~(0x3<<16));
    //设置由PF9管脚产生EXTI9事件
    //设置由PF8管脚产生EXTI8事件
    EXTI->EXTICR3 &= (~(0XFF<<0));
    EXTI->EXTICR3|= (0X05<<0);
    //通过下降沿检测EXTI8事件是否产生
    EXTI->FTSR1 |= (0x1<<8);
    //取消EXTI8中断屏蔽
    EXTI->C1IMR1 |= (0x1<<8);
    //设置EXTI8中断全局使能
    GICD->ISENABLER[3] |= (0x1<<2);
    //设置中断优先级
    GICD->IPRIORITYR[24] &= (~(0x1f<<19));
    //设置CPU0处理当前中断
    GICD->ITARGETSR[24] &=( ~(0x3<<16));
    GICD->ITARGETSR[24] |= (0x1<<16);
    //设置组0中断可以被转发到GICC层
    GICD->CTRL |=0X1;
 }

src/do_irq.c：

#include "stm32mp1xx_gic.h"
#include "stm32mp1xx_exti.h"
extern void printf(const char *fmt, ...);
unsigned int i = 0;
void do_irq(void) 
{
    //获取要处理的中断的中断号
    unsigned int irqno=GICC->IAR&0x3ff;
    switch (irqno)
    {
    case 99:
        printf("key1_intc\n");
        //清除GICD中断排队标志
        GICD->ICPENDR[3] |= (0X1<<3);
        //清除EXTI中断触发标志
        EXTI->FPR1 |= (0X1<<9);
        break;
    case 97:
        printf("key2_initc\n");
        //清除GICD中断排队标志
        GICD->ICPENDR[3] |= (0X1<<1);
        //清除EXTI中断触发标志
        EXTI->FPR1 |= (0X1<<7);
        break;
    case 98:
        printf("key3_initc\n");
        //清除GICD中断排队标志
        GICD->ICPENDR[3] |= (0X1<<2);
        //清除EXTI中断触发标志
        EXTI->FPR1 |= (0X1<<8);
        break;
    default:
        break;
    }
    //清除IAR寄存器中的中断号
    GICC->EOIR |= irqno;
}

main.c：

#include"uart.h"
#include"uart4.h"
#include"led.h"
#include"key_inc.h"
 
//封装比较函数
int strings_bijiao(const char* str1, const char* str2)
{
    while(*str1 && *str2)
    {
        if *str1 != *str2)
        {
            //字符不相等
            return 0; 
        }
        str1++;
        str2++;
    }
    if(*str1 == '\0' && *str2 == '\0')
    {
        //字符串相等
        return 1; 
    }
    else
    {
        //字符串长度不同，不相等
        return 0; 
    }
}
 
//封装延时函数
void delay(int ms)
{
    int i,j;
    for(i=0;i<ms;i++)
    {
        for(j=0;j<2000;j++);
    }
}
 
int main()
{
 
    //按键中断的初始化
    key1_it_config();
    key2_it_config();
    key3_it_config();
    while(1)
    {
        printf("in main pro\n");
        delay(1000);
    }
    return 0;
}
 

现象：