开关中断控制
main.c
#include "key_it.h"
#include "uart.h"
void delay(int ms)
{
int i,j;
for(i=0;i<ms;i++)
{
for(j=0;j<2000;j++);
}
}
int main()
{
key2_it_config();
key1_it_config();
key3_it_config();
all_led_init();
char buf[128];
gets(buf);
while (1)
{
puts(buf);
delay(1000);
}
}
// 最终现象:键盘输入a,串口工具显示b
?key_it.c
#include "key_it.h"
void key1_it_config()
{
//使能GPIOF时钟
RCC->MP_AHB4ENSETR |= (0x1<<5);
//设置PF9管脚为输入
GPIOF->MODER &= (~(0x3<<18));
//设置PF9作为EXTI9事件的输入
EXTI->EXTICR3 &= (~(0x1f<<8));
EXTI->EXTICR3 |= (0x05<<8);
//设置下降沿使能检测EXTI9事件
EXTI->FTSR1 |= (0x1<<9);
//设置EXTI9事件不屏蔽
EXTI->C1IMR1 |= (0x1<<9);
//GICD使能EXTI9(99号)中断
GICD->ISENABLER[3] |= (0x1<<3);
//GICD 设置99号中断的优先级
GICD->IPRIORITYR[24] &= (~(0x1f<<27));
//选择CPU0处理当前中断
GICD->ITARGETSR[24] |= (0x1<<24);
//全局使能组0中断被转发到GICC
GICD->CTRL |= (0X1);
//设置中断的优先级掩码
GICC->PMR |= (0x1f<<3);
//允许组0中断被CPU处理
GICC->CTRL |= (0x1);
}
void key3_it_config()
{
//使能GPIOF时钟
RCC->MP_AHB4ENSETR |= (0x1<<5);
//设置PF8管脚为输入
GPIOF->MODER &= (~(0x3<<16));
//设置PF8作为EXTI8事件的输入
EXTI->EXTICR3 &= (~(0xff<<0));
EXTI->EXTICR3 |= (0x05<<0);
//设置下降沿使能检测EXTI8事件
EXTI->FTSR1 |= (0x1<<8);
//设置EXTI8事件不屏蔽
EXTI->C1IMR1 |= (0x1<<8);
//-------------------------------------------------
//GICD使能EXTI8(98号)中断
GICD->ISENABLER[3] |= (0x1<<2);
//GICD 设置98号中断的优先级
GICD->IPRIORITYR[24] &= (~(0x1f<<19));
//选择CPU0处理当前中断
GICD->ITARGETSR[24] |= (0x1<<16);
//全局使能组0中断被转发到GICC
GICD->CTRL |= (0X1);
//设置中断的优先级掩码
GICC->PMR |= (0x1f<<3);
//允许组0中断被CPU处理
GICC->CTRL |= (0x1);
}
void key2_it_config()
{
//使能GPIOF时钟
RCC->MP_AHB4ENSETR |= (0x1<<5);
//设置PF7输入模式
GPIOF->MODER &=(~(0x3<<14));
//设置PF7作为EXTI7事件输入
EXTI->EXTICR2 &=(~(0xff<<24));
EXTI->EXTICR2 |=(0x5<<24);
//设置下降沿检测
EXTI->FTSR1 |=(0x1<<7);
//设置EXTI7事件不屏蔽
EXTI->C1IMR1 |=(0x1<<7);
//使能GICD中断
GICD->ISENABLER[3] |=(0x1<<1);
//设置GICD中断优先级
GICD->IPRIORITYR[24] &=(~(0x1f<<11));
//设置cpu0处理当前中断
GICD->ITARGETSR[24] |=(0x1<<8);
//全局使能使组0中断可以被转发到GICC
GICD->CTRL |=(0x1);
//设置优先级掩码
GICC->PMR |=(0x1f<<3);
//设置允许组0中断被cpu处理
GICC->CTRL |=(0x1);
}
do_it.c
#include "key_it.h"
#include "uart.h"
extern void printf(const char *fmt, ...);
unsigned int i = 0;
void do_irq(void)
{
int irqno = (GICC->IAR & 0x3ff);
switch (irqno)
{
case 99: // key1
puts("KEY1_INT\n");
// 清除GICD的中断排队标志
GICD->ICPENDR[3] |= (0x1<<3);
// 清除exti的事件触发标志
EXTI->FPR1 |= (0x1<<9);
break;
case 97: // KEY2
puts("KEY2_INT\n");
//清除GICD的中断排队标志
GICD->ICPENDR[3] |=(0x1<<1);
//清除EXTI的事件触发标志
EXTI->FPR1 |=(0x1<<7);
break;
case 98: // key3
led3_on();
// 清除GICD的中断排队标志
GICD->ICPENDR[3] |=(0x1<<2);
//清除EXTI的事件触发标志
EXTI->FPR1 |=(0x1<<8);
break;
}
// 清除中断号
GICC->EOIR = irqno;
}
key_it.h?
#ifndef __KEY_IT_H__
#define __KEY_IT_H__
#include"stm32mp1xx_gpio.h"
#include"stm32mp1xx_gic.h"
#include"stm32mp1xx_exti.h"
#include"stm32mp1xx_rcc.h"
void key1_it_config();
void key2_it_config();
void key3_it_config();
#endif