开发板mini2440灯
时间: 2023-09-12 15:05:23 浏览: 47
Mini2440是一款常见的嵌入式开发板,它的主板上有4个LED灯,分别是LED1、LED2、LED3和LED4。这些LED灯的控制引脚分别对应GPF4、GPF5、GPF6和GPF7。以下是使用C语言控制Mini2440的LED灯的示例代码:
```
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/types.h>
#include <fcntl.h>
#include <sys/mman.h>
#define LED1 4
#define LED2 5
#define LED3 6
#define LED4 7
unsigned int *gpfcon;
unsigned int *gpfdat;
void led_init(void)
{
int fd;
fd = open("/dev/mem", O_RDWR | O_SYNC);
if (fd == -1)
{
printf("open /dev/mem failed.\n");
exit(-1);
}
gpfcon = (unsigned int *)mmap(NULL, 16, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0x56000050);
if (gpfcon == MAP_FAILED)
{
printf("mmap failed.\n");
exit(-1);
}
gpfdat = gpfcon + 1;
*gpfcon &= ~((0x3 << (LED1*2)) | (0x3 << (LED2*2)) | (0x3 << (LED3*2)) | (0x3 << (LED4*2)));
*gpfcon |= ((0x1 << (LED1*2)) | (0x1 << (LED2*2)) | (0x1 << (LED3*2)) | (0x1 << (LED4*2)));
}
void led_on(int led)
{
*gpfdat &= ~(1 << led);
}
void led_off(int led)
{
*gpfdat |= (1 << led);
}
int main(int argc, char **argv)
{
led_init();
while (1)
{
led_on(LED1);
sleep(1);
led_off(LED1);
sleep(1);
}
return 0;
}
```
这段代码中,我们首先通过`mmap()`函数来映射物理地址到虚拟地址空间,然后设置LED灯的控制引脚为输出模式,并控制LED灯的亮灭状态。在`led_init()`函数中,我们将LED灯的控制引脚设置为输出模式,并将LED灯全部关闭。在`led_on()`和`led_off()`函数中,我们分别控制LED灯的亮和灭。在`main()`函数中,我们通过循环不断控制LED1的亮灭状态。