arm day6

串口通信控制led灯

uart.c?

#include"uart.h"



void all_led_init()

{

    RCC_GPIO |= (0X3<<4);//时钟使能

    GPIOE->MODER &=(~(0X3<<20));//设置PE10输出

    GPIOE->MODER |= (0X1<<20);

    //设置PE10为推挽输出

    GPIOE->OTYPER &=(~(0x1<<10));

    //PE10为低速输出

    GPIOE->OSPEEDR &= (~(0x3<<20));

    //设置无上拉下拉

    GPIOE->PUPDR &= (~(0x3<<20));

 

    //LED2

    GPIOF->MODER &=(~(0X3<<20));//设置Pf10输出

    GPIOF->MODER |= (0X1<<20);

    //设置Pf10为推挽输出

    GPIOF->OTYPER &=(~(0x1<<10));

    //Pf10为低速输出

    GPIOF->OSPEEDR &= (~(0x3<<20));

    //设置无上拉下拉

    GPIOF->PUPDR &= (~(0x3<<20));

 

    //LED3

    GPIOE->MODER &=(~(0X3<<16));//设置PE8输出

    GPIOE->MODER |= (0X1<<16);

    //设置PE8为推挽输出

    GPIOE->OTYPER &=(~(0x1<<8));

    //PE8为低速输出

    GPIOE->OSPEEDR &= (~(0x3<16));

    //设置无上拉下拉

    GPIOE->PUPDR &= (~(0x3<<16));

}

void led1_on()

{

    GPIOE->ODR |= (0x1<<10);

}

 

void led1_off()

{

    GPIOE->ODR &= (~(0x1<<10));

}

void led2_on()

{

    GPIOF->ODR |= (0x1<<10);

}

 

void led2_off()

{

    GPIOF->ODR &= (~(0x1<<10));

}

void led3_on()

{

    GPIOE->ODR |= (0x1<<8);

}

 

void led3_off()

{

    GPIOE->ODR &= (~(0x1<<8));

    

}

void uart4_config()

{

    //1.使能GPIOB\GPIOG\UART4外设时钟

    RCC->MP_AHB4ENSETR |= (0x1<<1);//gpiob

    RCC->MP_AHB4ENSETR |= (0x1<<6);//gpiog

    RCC->MP_APB1ENSETR |= (0x1<<16);//uart4

    //2.设置PB2\PG11用于UART4的管脚复用

    //设置PG11

    GPIOG->MODER &= (~(0x3<<22));

    GPIOG->MODER |= (0x2<<22);

    GPIOG->AFRH &= (~(0xf<<12));

    GPIOG->AFRH |= (0x6<<12);

    //设置PB2

    GPIOB->MODER &= (~(0x3<<4));

    GPIOB->MODER |= (0x2<<4);

    GPIOB->AFRL &= (~(0xF<<8));

    GPIOB->AFRL |= (0x8<<8);

    //禁用串口

    USART4->CR1 &= (~0x1);

    //3.设置数据位宽为8位

    USART4->CR1 &= (~(0x1<<12));

    USART4->CR1 &= (~(0x1<<28));

    //4.设置无奇偶校验位

    USART4->CR1 &= (~(0x1<<10));

    //5.设置16倍过采样

    USART4->CR1 &= (~(0x1<<15));

    //6.设置1位停止位

    USART4->CR2 &= (~(0x3<<12));

    //7.设置不分频

    USART4->PRESC &= (~0xf);

    //8.设置波特率为115200

    USART4->BRR=0X22B;

    //9.使能发送器

    USART4->CR1 |= (0x1<<3);

    //10.使能接收器

    USART4->CR1 |= (0x1<<2);

    //11.使能串口

    USART4->CR1 |= (0x1);

}

 

//字符串比较

int strcmp(const char *s1, const char *s2)

{

    for(int i=0; s1[i]!='\0' || s2[i] !='\0'; i++)

    {

            if(s1[i]!=s2[i])

            {

                return -1;

            }

    }

    return 0;

}

 

void putchar(char a)

{

    //1.先判断发送器是否为空，不为空等待

    while(!(USART4->ISR &(0x1<<7)));

    //2.向发送寄存器写入数据

    USART4->TDR=a;

    //3.等待发送完成

    while(!(USART4->ISR &(0x1<<6)));

}

 

char getchar()

{

    char a;

    //1.判断接收器是否有准备好的数据，没有就等待

    while(!(USART4->ISR &(0x1<<5)));

    //2.读取数据

    a=USART4->RDR;

    //3.返回

    return a;

}

 

//发送一个字符串

void puts(char *s)

{

    while(*s)

    {

        putchar(*s);

        s++;

    }

    putchar('\r');

    putchar('\n');

}

 

//接收一个字符串

void gets(char *s)

{

    while(1)

    {

        *s=getchar();

        putchar(*s);//键盘输入的内容在串口上回显

        if(*s=='\r')

        {

            *s='\0';

            break;

        }

        s++;

    }

    putchar('\n');

 

}

main.c

#include"uart.h"

 



 

 

 

int main()

 

{

 

    uart4_config();

 

    all_led_init();

 

    //char a;

 

    char buf[128];

 

    while(1)

 

    {

 

        /*//接收一个字符数据

 

         a=getchar();

 

         //发送接收的字符+1

 

         putchar(a+1);  

 

         putchar('\r'); 

 

         putchar('\n'); */



        gets(buf); // 读取字符串

 

        if(strcmp(buf,"led1_on") == 0)

 

        {

 

            //LED1亮

 

            led1_on();

 

        }

 

         if(strcmp(buf,"led1_off") == 0)

 

        {

 

            //LED1灭

 

            led1_off();

 

        }

 

 

 

        if(strcmp(buf,"led2_on") == 0)

 

        {

 

            //LED2亮

 

            led2_on();

 

        }

 

         if(strcmp(buf,"led2_off") == 0)

 

        {

 

            //LED2灭

 

            led2_off();

 

        }

 

 

 

        if(strcmp(buf,"led3_on") == 0)

 

        {

 

            //LED3亮

 

            led3_on();

 

        }

 

         if(strcmp(buf,"led3_off") == 0)

 

        {

 

            //LED3灭

 

            led3_off();

 

        }

 

        //puts(buf); // 输出字符串

 

 

 

    }

 

}

uart.h

#ifndef __UART4_H__

#define __UART4_H__

#include"stm32mp1xx_rcc.h"

#include"stm32mp1xx_gpio.h"

#include"stm32mp1xx_uart.h"

 #define RCC_GPIO (*(unsigned int*)0x50000a28)

 

void all_led_init();

void led1_on();

void led1_off();

void led2_on();

void led2_off();

void led3_on();

void led3_off();

 

 int strcmp(const char *s1, const char *s2);

void uart4_config();

void putchar(char a);

char getchar();

void gets(char *s);

void puts(char *s);

#endif