ARM:作业3

按键中断代码编写

代码:

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();#endif

key_it.c

#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;
}

do_irq.c

#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 << 3);//清除GICD中断标志位GICD->ICPENDR[3] = (0x1 << 3);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);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GICC->EOIR = irqno;
}

main.c

#include "key_it.h"//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(){//中断初始化key1_it_config();key2_it_config();key3_it_config();//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;}

运行结果: