[嵌入式]学习和理解STM32F103系列芯片的地址映射和寄存器映射原理

以 STM32最小系统核心板(STM32F103C8T6)+面板板+3只红绿蓝LED 搭建电路，使用GPIOB、GPIOC、GPIOD这3个端口控制LED灯（最高时钟2Mhz），轮流闪烁，间隔时长1秒。

一.程序设计思路

可以想象出，GPIO与时钟相关的寄存器都是很常用的寄存器，如果每一次操作这些IO口都需要看数据手册的话，太累，所以人家做芯片的把常用的寄存器对应的地址都设置好了，并放到一个头文件内，就是<stm32f10x.h>，修改main.c的代码，包含stm32f10x.h头文件。

1.GPIO模式

本次实验采用GPIOA、GPIOB、GPIOC三个端口。该三个端口都属于APB2总线

2.配置代码

在这里插入代码片#include "stm32f10x.h"
//----------------APB2??????? ---------------------
#define RCC_APB2ENR		*((unsigned volatile int*)0x40021018)
//----------------GPIOA????? -----------------------
#define GPIOA_CRL		*((unsigned volatile int*)0x40010800)
#define	GPIOA_ODR		*((unsigned volatile int*)0x4001080C)
//----------------GPIOB????? -----------------------
#define GPIOB_CRL		*((unsigned volatile int*)0x40010C00)
#define	GPIOB_ODR		*((unsigned volatile int*)0x40010C0C)
//----------------GPIOC????? -----------------------
#define GPIOC_CRH		*((unsigned volatile int*)0x40011004)
#define	GPIOC_ODR		*((unsigned volatile int*)0x4001100C)

extern void led(void);
//????
 void Delay()
 {
   u32 i=0;
   for(;i < 5000000;i++);
 }
 int main(void)
 {	
	 led();
	RCC_APB2ENR|=1<<2|1<<3|1<<4;			//APB2-GPIOA?GPIOB?GPIOC??????	
	
	GPIOA_CRL&=0xFFF0FFFF;		//??? ??	
	GPIOA_CRL|=0x00020000;		//PB5????
	GPIOA_ODR&=~(1<<4);			//???????
	
	GPIOB_CRL&=0xFF0FFFFF;		//??? ??	
	GPIOB_CRL|=0x00200000;		//PB5????
	GPIOB_ODR&=~(1<<5);			//???????
	 
	GPIOC_CRH&=0xF0FFFFFF;		//??? ??	
	GPIOC_CRH|=0x02000000;		//PB5????
	GPIOC_ODR&=~(1<<14);			//???????		
	 

	 

	while(1){

		//A?
		GPIOA_ODR|=1<<4;		//PB5???
	 	Delay();
		GPIOA_ODR&=~(1<<4);		//PB5???,????0,??????
		Delay();

		
		//B?
		GPIOB_ODR|=1<<5;		//PB5???
	 	Delay();
		GPIOB_ODR&=~(1<<5);		//PB5???,????0,??????
		Delay();

		
		
		//C?
		GPIOC_ODR|=1<<14;		//PB5???
	 	Delay();
		GPIOC_ODR&=~(1<<14);		//PB5???,????0,??????
		Delay();

		}
}

3.汇编代码

AREA MYDATA, DATA
	
 AREA MYCODE, CODE
	ENTRY
	EXPORT led

led
	;使能A,B,C
    ldr r0, =0x40021018
    ldr r1, =0x0000001c
    str r1, [r0]                


	;配置端口A4
	ldr r0, =0x40010800
    ldr r1, [r0]
    bic r1, r1, #0x000f0000
    orr r1, r1, #0x00010000
    str r1, [r0]

	;配置端口B5
    ldr r0, =0x40010c00
    ldr r1, [r0]
    bic r1, r1, #0x00f00000
    orr r1, r1, #0x00100000
    str r1, [r0]
	
	;配置端口C14
	ldr r0, =0x40011004
    ldr r1, [r0]
    bic r1, r1, #0x0f000000
    orr r1, r1, #0x01000000
    str r1, [r0]

	;初始为A4亮灯
	ldr r0, =0x4001080c
    ldr r1, =0x00000010
    str r1, [r0]

	ldr r0, =5000000;频率
    ldr r1, =0
	
;循环亮灯	
blink
    add r1, r1, #1
    cmp r1, r0
    blt blink
	
	;A4灭
	ldr r1, =0x4001080c
    ldr r2, [r1]
    eor r2, r2, #0x00000010
    str r2, [r1]
	
	;B5亮
	ldr r1, =0x40010c0c
    ldr r2, [r1]
    eor r2, r2, #0x00000020
    str r2, [r1]
	
	ldr r1, =0

blink1	
	add r1, r1, #1
    cmp r1, r0
    blt blink1
	
	;B5灭
	ldr r1, =0x40010c0c
    ldr r2, [r1]
    eor r2, r2, #0x00000020
    str r2, [r1]
	
	;C14亮
	ldr r1, =0x4001100c
    ldr r2, [r1]
    eor r2, r2, #0x00004000
    str r2, [r1]
	

	ldr r1, =0

blink2
	add r1, r1, #1
    cmp r1, r0
    blt blink2
	
	;C14灭
	ldr r1, =0x4001100c
    ldr r2, [r1]
    eor r2, r2, #0x00004000
    str r2, [r1]
	
	;A4亮
	ldr r1, =0x4001080c
    ldr r2, [r1]
    eor r2, r2, #0x00000010
    str r2, [r1]
	

	ldr r1, =0
    b blink

	
	END

2.效果

视频

1.总结

这次博客的内容我花费了许多时间，但是也学到了非常多的知识

参考资料
STM32寄存器点亮流水灯的三种方法
STM32用汇编点亮LED灯
stm32寄存器实现流水灯