Arm 点灯实验
1.汇编代码点灯
.text
.global _start
_start:
/**********LED1点灯RCC和GPIO章节初始化**************/
LED1_init:
// @ 1.通过RCC_AHB4_ENSETR:0x50000A28寄存器设置GPIOE控制器时钟使能 [0x50000A28][4] = 1
ldr r0,=0x50000A28
ldr r1,[r0]
orr r1,r1,#(0x1 << 4)
orr r1,r1,#(0x1 << 5)
str r1,[r0]
// @ 2.通过GPIOE_MODER:0x50006000寄存器设置PE10引脚为输出模式[0x50006000][21:20] = 01
// @ 3.通过GPIO_OTYPER:0x50006004寄存器设置PE10引脚为推挽输出模式 [0x50006004][10] = 0
// @ 4.通过GPIO_OSPEEDR:0x50006008寄存器设置PE10引脚为低速输出模式 [0x50006008][21:20] = 00
// @ 5.通过GPIO_PUPDR:0x5000600C寄存器设置PE10引脚为禁止上下拉电阻 [0x5000600C][21:20] = 00
/*设置PE10引脚为输出模式*/
ldr r0,=0x50006000
ldr r1,[r0]
bic r1,r1,#(0x3<<20)
bic r1,r1,#(0x3<<16)
orr r1,r1,#(0x1<<20)
orr r1,r1,#(0x1<<16)
str r1,[r0]
//led2
ldr r0,=0x50007000
ldr r1,[r0]
bic r1,r1,#(0x3<<20)
orr r1,r1,#(0x1<<20)
str r1,[r0]
/*设置PE10引脚为推挽输出*/
ldr r0,=0x50006004
ldr r1,[r0]
bic r1,r1,#(0x1<<10)
bic r1,r1,#(0x1<<8)
str r1,[r0]
//LED2
ldr r0,=0x50007004
ldr r1,[r0]
bic r1,r1,#(0x1<<10)
str r1,[r0]
/*设置PE10引脚为低速输出*/
ldr r0,=0x50006008
ldr r1,[r0]
bic r1,r1,#(0x3<<20)
bic r1,r1,#(0x3<<16)
str r1,[r0]
//LED2
ldr r0,=0x50007008
ldr r1,[r0]
bic r1,r1,#(0x3<<20)
str r1,[r0]
/*设置PE10引脚禁止上下拉电阻*/
ldr r0,=0x5000600c
ldr r1,[r0]
bic r1,r1,#(0x3<<20)
bic r1,r1,#(0x3<<16)
str r1,[r0]
//led2
ldr r0,=0x5000700c
ldr r1,[r0]
bic r1,r1,#(0x3<<20)
str r1,[r0]
LED1_ON:
// @ 1.通过GPIOE_ODR:0x50006014寄存器设置PE10引脚为输出高电平[0x50006014][10] = 1
/*设置PE10引脚输出*/
ldr r0,=0x50006014
ldr r1,[r0]
orr r1,r1,#(0x1<<10)
str r1,[r0]
bl delay_1s
//熄灭
ldr r0,=0x50006014
ldr r1,[r0]
bic r1,r1,#(0x1<<10)
str r1,[r0]
bl delay_1s
ldr r0,=0x50007014
ldr r1,[r0]
orr r1,r1,#(0x1<<10)
str r1,[r0]
bl delay_1s
//熄灭
ldr r0,=0x50007014
ldr r1,[r0]
bic r1,r1,#(0x1<<10)
str r1,[r0]
bl delay_1s
ldr r0,=0x50006014
ldr r1,[r0]
orr r1,r1,#(0x1<<8)
str r1,[r0]
bl delay_1s
ldr r0,=0x50006014
ldr r1,[r0]
bic r1,r1,#(0x1<<8)
str r1,[r0]
bl delay_1s
b LED1_ON
// @ 1.通过GPIOE_ODR:0x50006014寄存器设置PE10引脚为输出低电平[0x50006014][10] = 0
//@ 大概1s的延时函数
delay_1s:
mov r3, #0x10000000
mm:
cmp r3, #0
subne r3, r3, #1
bne mm
mov pc, lr
.end
2.c语言点灯
2.1 头文件
#ifndef __LED_H__
#define __LED_H__
//定时器的使能
#define RCC_MP_AHB4ENSETR (*(volatile unsigned int *)0x50000A28)
//枚举3栈灯
typedef enum{
LED1=1,
LED2,
LED3,
}leds_t;
typedef enum{
GPIO_SET=0,
GPIO_RESET,
}led_status_t;
//1.封装寄存器 封装RCC外设的寄存器，GPIOE GPIOF
typedef struct {
volatile unsigned int MODER;
volatile unsigned int OTYPER;
volatile unsigned int OSPEEDR;
volatile unsigned int PUPDR;
volatile unsigned int IDR;
volatile unsigned int ODR;
}gpio_t;
#define GPIOA ((gpio_t *)0x50002000)
#define GPIOB ((gpio_t *)0x50003000)
#define GPIOC ((gpio_t *)0x50004000)
#define GPIOD ((gpio_t *)0x50005000)
#define GPIOE ((gpio_t *)0x50006000)
#define GPIOF ((gpio_t *)0x50007000)
//led灯的初始化
void hal_led_init(void);
//led灯的亮灭 参数：leds_t 那个灯， led_status_t 灯的状态
void hal_led_switch(leds_t , led_status_t);
#endif //__LED_H__2.2 源文件
#include "../include/led.h"
// led灯的初始化
void hal_led_init(void)
{
// 1. 使能GPIOE,GPIOF外设的时钟
RCC_MP_AHB4ENSETR |= (0x3 << 4);
// 2. 设置gpio引脚为输出模式
GPIOE->MODER &= (~(0x3 << 20));
GPIOE->MODER |= (0x1 << 20);
GPIOE->MODER &= (~(0x3 << 16));
GPIOE->MODER |= (0x1 << 16);
GPIOF->MODER &= (~(0x3 << 20));
GPIOF->MODER |= (0x1 << 20);
// 3. 设置gpio引脚为推挽输出
GPIOE->OTYPER &= (~(0x1 << 10));
GPIOE->OTYPER &= (~(0x1 << 8));
GPIOF->OTYPER &= (~(0x1 << 10));
// 4. 设置gpio引脚为低速模式
GPIOE->OSPEEDR &= (~(0x3 << 20));
GPIOE->OSPEEDR &= (~(0x3 << 16));
GPIOF->OSPEEDR &= (~(0x3 << 20));
// 5. 禁止gpio引脚的上拉和下拉
GPIOE->PUPDR &= (~(0x3 << 20));
GPIOE->PUPDR &= (~(0x3 << 16));
GPIOF->PUPDR &= (~(0x3 << 20));
}
/*
功能LED灯的亮灭
*/
void hal_led_switch(leds_t leds, led_status_t statu)
{
// 设置led灯亮
switch (leds)
{
case LED1:
if (statu == GPIO_SET)
{
GPIOE->ODR &= (~(0x1 << 10));
}
else
{
GPIOE->ODR |= (0x1 << 10);
}
break;
case LED2:
if (statu == GPIO_SET)
{
GPIOF->ODR &= (~(0x1 << 10));
}
else
{
GPIOF->ODR |= (0x1 << 10);
}
break;
case LED3:
if (statu == GPIO_SET)
{
GPIOE->ODR &= (~(0x1 << 8));
}
else
{
GPIOE->ODR |= (0x1 << 8);
}
break;
default:
break;
}
}2.3主函数
#include "./include/led.h"
extern void printf(const char *fmt, ...);
void delay_ms(unsigned int ms)
{
int i,j;
for(i = 0; i < ms;i++)
for (j = 0; j < 1800; j++);
}
int main()
{
// 初始化
hal_led_init();
while(1)
{
// 实现LED灯的交替闪烁
hal_led_switch(LED1,GPIO_RESET);
delay_ms(500);
hal_led_switch(LED1,GPIO_SET);
hal_led_switch(LED2,GPIO_RESET);
delay_ms(500);
hal_led_switch(LED2,GPIO_SET);
hal_led_switch(LED3,GPIO_RESET);
delay_ms(500);
hal_led_switch(LED3,GPIO_SET);
}
return 0;
}