do_irq.c

判断中断号

#include "key_it.h"
extern void printf(const char *fmt, ...);
unsigned int i = 0;
void do_irq(void)
{// 获取中断号，根据中断号的不同进行不同的中断处理int irqno;irqno = GICC->IAR & 0x3ff;switch (irqno){case 99:printf("key1 int\n");// 清除exti中断标志位EXTI->FPR1 |= (0x1 << 9);// 清除GICD中断标志位  99/32=3...3GICD->ICPENDR[3] = (0x1 << 3);led1_on();break;case 97:printf("key2 int\n");// 清除exti中断标志位EXTI->FPR1 |= (0x1 << 7);// 清除GICD中断标志位GICD->ICPENDR[3] = (0x1 << 1);led1_off();break;case 98:printf("key3 int\n");// 清除exti中断标志位EXTI->FPR1 |= (0x1 << 8);// 清除GICD中断标志位GICD->ICPENDR[3] = (0x1 << 2);break;}// 清除IAR寄存器的值,也就是中断号GICC->EOIR = irqno;
}

 key_it.c

按钮操作

#include "key_it.h"void key1_it_config()
{//1.设置GPIOF时钟使能RCC->MP_AHB4ENSETR |= (0X1 << 5);// 2.将PF9管脚设置为输入GPIOF->MODER &= (~(0x3 << 18));//3.设置由PF9产生EXTI9事件EXTI->EXTICR3 &= (~(0XFF << 8));EXTI->EXTICR3 |= (0x05 << 8);// 4.设置EXTI9事件的检测方式为下降沿检测EXTI->FTSR1 |= (0x1 << 9);// 5.允许中断不屏蔽，可以被转发到GICEXTI->C1IMR1 |= (0x1 << 9);// 6.允许EXTI9（99号）中断被保存在组0中GICD->ISENABLER[3] |= (0x1 << 3);// 7.设置99号中断优先级GICD->IPRIORITYR[24] &= (~(0x1f << 27));GICD->IPRIORITYR[24] |= (0x0 << 27);// 8.设置99号中断可以被CPU0处理GICD->ITARGETSR[24] &= (~(0x3 << 24));GICD->ITARGETSR[24] |= (0x1 << 24);//9.允许99号中断被转发到CPU接口层GICD->CTRL |= 0x1;//10.设置中断优先级掩码GICC->PMR |= (0x1f << 3);//11.允许中断被转发给CPU处理GICC->CTRL |= 0x1;
}
void key2_it_config()
{//1.设置GPIOF时钟使能RCC->MP_AHB4ENSETR |= (0X1 << 5);// 2.将PF7管脚设置为输入GPIOF->MODER &= (~(0x3 << 14));//3.设置由PF7产生EXTI7事件EXTI->EXTICR2 &= (~(0XFF << 24));EXTI->EXTICR2 |= (0x05 << 24);// 4.设置EXTI7事件的检测方式为下降沿检测EXTI->FTSR1 |= (0x1 << 7);// 5.允许中断不屏蔽，可以被转发到GICEXTI->C1IMR1 |= (0x1 << 7);// 6.允许EXTI7（97号）中断被保存在组0中GICD->ISENABLER[3] |= (0x1 << 1);// 7.设置97号中断优先级GICD->IPRIORITYR[24] &= (~(0x1f << 11));GICD->IPRIORITYR[24] |= (0x0 << 11);// 8.设置97号中断可以被CPU0处理GICD->ITARGETSR[24] &= (~(0x3 << 8));GICD->ITARGETSR[24] |= (0x1 << 8);//9.允许97号中断被转发到CPU接口层GICD->CTRL |= 0x1;//10.设置中断优先级掩码GICC->PMR |= (0x1f << 3);//11.允许中断被转发给CPU处理GICC->CTRL |= 0x1;
}
void key3_it_config()
{//1.设置GPIOF时钟使能RCC->MP_AHB4ENSETR |= (0X1 << 5);// 2.将PF8管脚设置为输入GPIOF->MODER &= (~(0x3 << 16));//3.设置由PF8产生EXTI8事件EXTI->EXTICR3 &= (~(0XFF << 0));EXTI->EXTICR3 |= (0x05 << 0);// 4.设置EXTI8事件的检测方式为下降沿检测EXTI->FTSR1 |= (0x1 << 8);// 5.允许中断不屏蔽，可以被转发到GICEXTI->C1IMR1 |= (0x1 << 8);// 6.允许EXTI8（98号）中断被保存在组0中 98/32=3...2GICD->ISENABLER[3] |= (0x1 << 2);// 7.设置98号中断优先级   98/4=24...2     2*8+3=19GICD->IPRIORITYR[24] &= (~(0x1f << 19));GICD->IPRIORITYR[24] |= (0x0 << 19);// 8.设置98号中断可以被CPU0处理 98/4=24...2GICD->ITARGETSR[24] &= (~(0x3 << 16));GICD->ITARGETSR[24] |= (0x1 << 16);//9.允许97号中断被转发到CPU接口层GICD->CTRL |= 0x1;//10.设置中断优先级掩码GICC->PMR |= (0x1f << 3);//11.允许中断被转发给CPU处理GICC->CTRL |= 0x1;
}
void all_led_init()
{//1.使能外设时钟(*((unsigned int*)0X50000A28)) |= (0x3<<4);//2.设置PF9为输出输出(*((unsigned int*)0X50007000)) &= (~(0x3<<12));(*((unsigned int*)0X50007000)) |= (0x1<<12);//3.设置推挽输出(*((unsigned int*)0X50007004)) &= (~(0x1<<6));//4.设置输出速度为低速(*((unsigned int*)0X50007008)) &= (~(0x3<<12));
//5.设置无上拉下拉(*((unsigned int*)0X5000700c)) &= (~(0x3<<12));}void led1_on()
{(*((unsigned int*)0X50007014)) |= (0x1<<6);}void led1_off()
{(*((unsigned int*)0X50007014)) &= (~(0x1<<6));}

key_it.h

#ifndef __KEY_IT_H__
#define __KEY_IT_H__
#include "stm32mp1xx_gpio.h"
#include "stm32mp1xx_exti.h"
#include "stm32mp1xx_rcc.h"
#include "stm32mp1xx_gic.h"void key1_it_config();
void key2_it_config();
void key3_it_config();
void all_led_init();
void led1_on();
void led1_off();
#endif

main.c

#include "key_it.h"void delay(int ms){int i,j;for(i=0;i<ms;i++){for(j=0;j<2000;j++);}}int main(){//中断初始化key1_it_config();key2_it_config();key3_it_config();all_led_init();//现象是发送一个a串口工具打印一个bwhile(1){printf("main func\n");delay(2000);}return 0;}