RT-Thread-【Numaker-IoT-M487】SD接口验证RT-Thread问答社区

【Numaker-IoT-M487】SD接口验证

发布于 2022-04-16 19:28:09 浏览：739 订阅该版

**简介**
本文主要介绍基于Numaker-IoT-M487开发板的SD卡功能验证，由于为初次使用RT-Thread系统，摸索了一下使用，感觉还是挺容易上手的系统，鉴于理解有限，后文中如有理解错误之处，还请大佬指出，在此先谢谢了，闲言少续，直奔主题。
**环境搭建**
验证所需硬件环境：
- Numaker-IoT-M487开发板
- Micro-USB线
- SD卡
- 读卡器
验证使用软件环境
- RT-Thread Studio IDE
- RT-Thread OS version 4.0.4
- Numaker-IoT-M487 SDK库version 1.0.0
1. 硬件接线如下图
![微信图片_20220416172047.jpg](https://oss-club.rt-thread.org/uploads/20220416/9ed28e1a62e6b7e79f92e83f0f95eb2a.jpg.webp)
![微信图片_20220416172232.jpg](https://oss-club.rt-thread.org/uploads/20220416/f95d967b87c107f3999edffd62d1a28e.jpg)
2、硬件对应原理图接口如下图
![image.png](https://oss-club.rt-thread.org/uploads/20220416/c544d3b708d652da0896a674c7e54482.png)
![image.png](https://oss-club.rt-thread.org/uploads/20220416/4607a385af7816fba925a000be29e1ae.png)
![image.png](https://oss-club.rt-thread.org/uploads/20220416/cb0aad2a33c1eb30af136b0be2442512.png)
**验证流程介绍**
1. RT-Thread Studio软件环境搭建、板载SDK包下载以及搭建基础test工程方法这里就不单独介绍了，详细可参考[https://club.rt-thread.org/ask/article/3668.html]
2. SD卡系统驱动验证配置
双击工程中RT-Thread Settings进入RT-Thread系统配置界面，依次设置如下
![image.png](https://oss-club.rt-thread.org/uploads/20220416/665e5d269deddec8251ff6eaad321274.png)
![image.png](https://oss-club.rt-thread.org/uploads/20220416/389db8bdb33ba2bdd14c3db1618d462d.png)
![image.png](https://oss-club.rt-thread.org/uploads/20220416/95efcf2f8c67164acc93e3bba1924801.png)
然后保存
2. 验证代码添加
```
void SD_RD_Test()
{
#define Data_Size (30*1024)

static uint8_t data_buff[Data_Size]="hello world!";

uint32_t t1=0;
    uint32_t t2=0;
    uint32_t t=0;

int fd = open("/test.txt",O_WRONLY|O_CREAT);
    if (fd<0)
    {
        rt_kprintf("open fail\n");
        return ;
    }

t1=rt_tick_get();
    write(fd, data_buff, Data_Size);
    t2=rt_tick_get();
    t=t2-t1;
    rt_kprintf("write SD time:%d ms\n",t);

close(fd);
    rt_kprintf("write sucess\n");

rt_thread_mdelay(500);

fd = open("/test.txt",O_RDONLY);
    if (fd<0)
    {
        rt_kprintf("open fail\n");
        return ;
    }
    memset(data_buff,0,Data_Size);

t1=rt_tick_get();
    read(fd, data_buff, Data_Size);
    t2=rt_tick_get();
    t=t2-t1;
    rt_kprintf("read SD time:%d ms\n",t);

close(fd);
    rt_kputs(data_buff);
}
```
```
int main(int argc, char **argv)
{
#if defined(RT_USING_PIN)

int counter = 0;

/* set LEDR1 pin mode to output */
    rt_pin_mode(LEDR, PIN_MODE_OUTPUT);
    rt_pin_mode(LEDG, PIN_MODE_OUTPUT);
    rt_pin_mode(LEDY, PIN_MODE_OUTPUT);

while (counter < 1)
    {
        rt_pin_write(LEDR, PIN_HIGH);
        rt_pin_write(LEDG, PIN_LOW);
        rt_pin_write(LEDY, PIN_HIGH);
        rt_thread_mdelay(500);
        rt_pin_write(LEDR, PIN_LOW);
        rt_pin_write(LEDG, PIN_HIGH);
        rt_pin_write(LEDY, PIN_LOW);
        rt_thread_mdelay(500);
        //rt_kprintf("Led process\n");
        SD_RD_Test();
    }

#endif
    return 0;
}
```
添加完成，编译下载至MCU中，查看运行效果
**验证效果展示**
1、Log输出结果
![image.png](https://oss-club.rt-thread.org/uploads/20220416/afd4d078ce72e018887e23436fc9d2cb.png)
Log输出与程序一致
2、将SD卡取下，放置读卡器中，插入电脑，查看SD中的文件数据
![image.png](https://oss-club.rt-thread.org/uploads/20220416/1ae842ff5f7c46cc32e74e942f2448f1.png)
SD中文件内容与程序写入内容一致
3、读写速度测试，测试读写size大小为30K，读写时间如下
![image.png](https://oss-club.rt-thread.org/uploads/20220417/b3a22aca1782748171e15160665c0d80.png)
估算读写速度为：
- 写入速度：2325kb/s 
- 读取速度：4347kb/s
**总结**
初次使用RT-Thread Studio配置RT-Thread OS系统，配置挺方便的，但需要对系统先有一些基础的认识，为方便大家开发，上传下开发手册至此 [rtthread_manual.zh.pdf](https://oss-club.rt-thread.org/uploads/20220416/ce05f9ebd2a31a0015a328c138b2dcf6.pdf)。