smt32-f103寄存器点灯

stm32
Author

dd21

Published

December 5, 2022

STM32F103寄存器点灯

通过寄存器中的状态来设置引脚状态 LED在GPIOB的第5引脚

// RCC_ENR RCC must be first otherwise the LED can not be lighted
    *(unsigned int*)0x40021018 |= (1<<3);
    // port B   base address 0x4001 0c00

    // output type is pull and push
    *(unsigned int*)0x40010C00 |= ((1)<<(4*0));
    //*(unsigned int*)0x40010C00 |= ((1)<<(8*0));
    

    // port B odr address is base address add 0x0c  
    *(unsigned int*)0x40010C0C &= ~(1<<0);
    //*(unsigned int*)0x40010C0C &= ~(1<<2);

封装GPIO

// REG mapping 
#define PERIPH_BASE                 ((unsigned int) 0x40000000)
    
#define APB1_PERIPH_BASE         PERIPH_BASE
#define APB2_PERIPH_BASE        (PERIPH_BASE+0x10000)
#define AHB_PERIPH_BASE         (PERIPH_BASE+0x20000)

#define RCC_BASE                        (AHB_PERIPH_BASE+0x1000)
#define GPIOB_BASE                      (APB2_PERIPH_BASE +0x0C00)

#define RCC_APB2ENR                     *(unsigned int*)(RCC_BASE+0x18)
    
#define GPIOB_CRL                       *(unsigned int*)(GPIOB_BASE+0x00)
#define GPIOB_CRH                       *(unsigned int*)(GPIOB_BASE+0x04)
#define GPIOB_ODR                       *(unsigned int*)(GPIOB_BASE+0x0C)
    
#define GPIOB_BSRR                  *(unsigned int*)(GPIOB_BASE+0x10)
#define GPIOB_BRR                       *(unsigned int*)(GPIOB_BASE+0x14)
#define GPIOB_LOCK                      *(unsigned int*)(GPIOB_BASE+0x18)

typedef unsigned int        uint32_t;
typedef unsigned short  uint16_t; 

typedef struct{
    uint32_t CRL; 
    uint32_t CRH; 
    uint32_t IDL; 
    uint32_t ODR; 
    uint32_t BSRR; 
    uint32_t BRR; 
    uint32_t LCKR;  
}GPIO_Struct; 

// change the GPIO type to GPIO_Struct then can use the REG like [GPIO_Struct->RCC] 
#define GPIOB ((GPIO_Struct*)GPIOB_BASE)

    RCC_APB2ENR |= (1<<3);

    GPIOB->CRL |= ((1)<<(4*0));
    
    // open LED set 0
    //GPIOB->ODR &= ~(1<<0);
    // off LED set 1
    GPIOB->ODR |= (1<<0);

简单封装

    RCC_APB2ENR |= (1<<3);

    GPIOB_CRL |= ((1)<<(4*0));
    
    // open LED set 0
    GPIOB_ODR &= ~(1<<0);
    // off LED set 1
    //GPIOB_ODR |= (1<<0);