2022.12.29---KEY

最新推荐文章于 2023-09-03 20:31:16 发布

原创最新推荐文章于 2023-09-03 20:31:16 发布 · 150 阅读

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#单片机 #stm32 #嵌入式硬件

本文介绍了STM32微控制器中按键中断功能的实现方法，包括按键1、按键2和按键3的初始化过程及对应的中断处理函数。通过配置GPIO、EXTI等寄存器来实现外部中断，并详细展示了如何设置中断优先级、中断屏蔽等。

实现按键中断功能

//key.c
#include "key.h"

//按键1初始化
void key1_init()
{
	//使能GPIOF组控制器
	RCC->MP_AHB4ENSETR |= (0x1<<5);

	//设置GPIOF模式为输入模式
	GPIOF->MODER &= (~(0x3<<18));

	//设置中断选择寄存器
	EXTI->EXTICR3 &= (~(0xff<<8));
	EXTI->EXTICR3 |= (0x05<<8);
	//设置中断下降沿触发寄存器
	EXTI->FTSR1 |= (0x1<<9);
	//设置中断屏蔽寄存器
	EXTI->C1IMR1 |= (0x1<<9);

	//使能GICD层
	GICD->CTRL |= 0x1;
	//设置中断设置使能寄存器
	GICD->ISENABLER[3] |= (0x1<<3);
	//设置中断优先级寄存器
	GICD->IPRIORITYR[24] &= (~(0x1f<<27));
	GICD->IPRIORITYR[24] |= (0x1<<27);
	//设置中断目标分配寄存器
	GICD->ITARGETSR[24] &= (~(0x3<<24));
	GICD->ITARGETSR[24] |= (0x1<<24);

	//使能GICC层
	GICC->CTRL |= 0x1;
	//设置中断优先级屏蔽寄存器
	GICC->PMR &= (~(0x1f<<3));
	GICC->PMR |= (0x1f<<3);

}


//按键2初始化
void key2_init()
{
//	RCC->MP_AHB4ENSETR |= (0x1<<5);

	GPIOF->MODER &= (~(0x3<<14));

	EXTI->EXTICR2 &= (~(0xff<<24));
	EXTI->EXTICR2 |= (0x05<<24);
	EXTI->FTSR1 |= (0x1<<7);
	EXTI->C1IMR1 |= (0x1<<7);

	GICD->CTRL |= 0x1;
	GICD->ISENABLER[3] |= (0x1<<1);
	GICD->IPRIORITYR[24] &= (~(0x1f<<11));
	GICD->IPRIORITYR[24] |= (0x2<<11);
	GICD->ITARGETSR[24] &= (~(0x3<<8));
	GICD->ITARGETSR[24] |= (0x1<<8);

	GICC->CTRL |= 0x1;
	GICC->PMR &= (~(0x1f<<3));
	GICC->PMR |= (0x1f<<3);

}


//按键3初始化
void key3_init()
{
//	RCC->MP_AHB4ENSETR |= (0x1<<5);

	GPIOF->MODER &= (~(0x3<<16));

	EXTI->EXTICR3 &= (~(0xff));
	EXTI->EXTICR3 |= (0x05);
	EXTI->FTSR1 |= (0x1<<8);
	EXTI->C1IMR1 |= (0x1<<8);

	GICD->CTRL |= 0x1;
	GICD->ISENABLER[3] |= (0x1<<2);
	GICD->IPRIORITYR[24] &= (~(0x1f<<19));
	GICD->IPRIORITYR[24] |= (0x3<<19);
	GICD->ITARGETSR[24] &= (~(0x3<<16));
	GICD->ITARGETSR[24] |= (0x1<<16);

	GICC->CTRL |= 0x1;
	GICC->PMR &= (~(0x1f<<3));
	GICC->PMR |= (0x1f<<3);

}

//中断处理函数
#include "stm32mp1xx_gpio.h"
#include "stm32mp1xx_exti.h"
#include "stm32mp1xx_gic.h"

extern void printf(const char *fmt, ...);
unsigned int i = 0;
void do_irq(void) 
{
	int irq_num;
	//接收按下按键的中断号
	irq_num=GICC->IAR & 0x3ff;
	//判断是哪个按键按下
	switch (irq_num)
	{
	case 97:
			printf("---KEY2---\n");
			//清除中断挂起标志
			EXTI->FPR1 |= (0x1<<7);
			//清除GICD层挂起标志
			GICD->ICPENDR[3] |= (0x1<<1);
			break;
	case 98:
			printf("---KEY3---\n");
			EXTI->FPR1 |= (0x1<<8);
			GICD->ICPENDR[3] |= (0x1<<2);
			break;
	case 99:
			printf("---KEY1---\n");
			EXTI->FPR1 |= (0x1<<9);
			GICD->ICPENDR[3] |= (0x1<<3);
			break;
	default:break;
	}
	//清除中断号
	GICC->EOIR=irq_num;
}