大家在STM32F2上用SPI通过文件系统读写SD能达到什么速度？

发布于 2012-08-26 17:12:05 浏览：5806 订阅该版

这个是我在一张４G SDHC上测的，已经用了ＤＭＡ，ＳＰＩ的速度是ＰＣＬＫ２／４＝１５Ｍ．测试文件１０ＭＢ，写的时候每次写２５６字节，读的时候也是２５６字节．

```  | /                                                                          
- RT -     Thread Operating System                                              
 / |      1.0.2 build Aug 26 2012                                              
 2006 - 2011 Copyright by rt-thread team                                        
found part[0], begin: 4194304, size: 3.704GB                                    
SPI SD init OK                                                                  
File System initialized!                                                        
                                                                                
LCD Device ID : 9335                                                            
 finsh>>file_test()                                                             
File speed test with 10MB write and read of 256bytes a block                    
Writing ... speed 39 kB/s                                                       
Reading ... speed 646 kB/s                                                      
	0, 0x00000000                                                                  
finsh>>                             ```

虽然够用，不过比预想的慢，不知道大家的ＳＤ在ＳＰＩ上能达到什么速度？

9 个回答

presto 2012-08-26

这家伙很懒，什么也没写！

aozima 2012-08-26

调网络不抓包，调I2C等时序不上逻辑分析仪，就像电工不用万用表！多用整理的好的文字，比截图更省流量，还能在整理过程中思考。

presto 2012-08-26

这家伙很懒，什么也没写！

ＳＰＩ的速度从１５Ｍ提高到３０Ｍ，对写入速度几乎没有影响，读出速度提高２０％左右．

```
 | /                                                                          
- RT -     Thread Operating System                                              
 / |      1.0.2 build Aug 26 2012                                              
 2006 - 2011 Copyright by rt-thread team                                        
found part[0], begin: 4194304, size: 3.704GB                                    
SPI SD init OK                                                                  
File System initialized!                                                        
                                                                                
LCD Device ID : 9335                                                            
 finsh>>file_test()                                                             
File speed test with 10MB write and read of 256bytes a block                    
Writing ... speed 39 kB/s                                                       
Reading ... speed 788 kB/s                                                      
	0, 0x00000000                                                                  
finsh>>                              
```

presto 2012-08-26

这家伙很懒，什么也没写！

aozima 2012-08-26

调网络不抓包，调I2C等时序不上逻辑分析仪，就像电工不用万用表！多用整理的好的文字，比截图更省流量，还能在整理过程中思考。

presto 2012-08-26

这家伙很懒，什么也没写！

再上一张３２Ｍ老卡的测试结果，速度降到１５Ｍ，好像不怎么比Ｃ１０的差。

```
 | /                                                                          
- RT -     Thread Operating System                                              
 / |      1.0.2 build Aug 26 2012                                              
 2006 - 2011 Copyright by rt-thread team                                        
found part[0], begin: 26112, size: 29.678MB                                     
SPI SD init OK                                                                  
File System initialized!                                                        
                                                                                
LCD Device ID : 9335                                                            
 finsh>>file_test()                                                             
File speed test with 10MB write and read of 256bytes a block                    
Writing ... speed 40 kB/s                                                       
Reading ... speed 604 kB/s                                                      
	0, 0x00000000                                                                  
finsh>>               
```

aozima 2012-08-26

调网络不抓包，调I2C等时序不上逻辑分析仪，就像电工不用万用表！多用整理的好的文字，比截图更省流量，还能在整理过程中思考。

找了张2G的卡，SD卡驱动程序是自己写的，不是用的ST发布的。

测试程序就是RT-Thread发布包里面的。（examples/file/）

卡识别信息：（SPI时钟为10M，非DMA方式，CPU性能应该在F2的一半左右）
>| /
>- RT -     Thread Operating System
> / |      1.0.1 build Aug 25 2012
> 2006 - 2011 Copyright by rt-thread team
>[MSD] 0 [info] SD card goto IDLE mode OK!
>[MSD] 0 [info] CMD8 response : 0x05 0xFF 0xFF 0xFF 0xFF
>[MSD] 0 [info] CMD8 is illegal command.
>[MSD] 1 [info] maybe Ver1.X SD Memory Card or MMC card!
>[MSD] 1 [info] OCR is 0x00FF8000
>[MSD] 1 [info] It is Ver1.X SD Memory Card!!!
>[MSD] 1 [info] CSD Version 1.0
>[MSD] 1 [info] TRAN_SPEED: 0x32, 10Mbit/s.
>[MSD] 1 [info] CSD : READ_BL_LEN : 10 1024byte
>[MSD] 2 [info] CSD : C_SIZE : 3828
>[MSD] 2 [info] CSD : C_SIZE_MULT : 7
>[MSD] 2 [info] card capacity : 1914 Mbyte
>File System initialized!

---

写入速度：
>finsh />writespeed("/test.bin", 327680, 256)
>File write speed: 7680 byte/s
>
>finsh />writespeed("/test.bin", 327680, 512)
>File write speed: 7680 byte/s
>
>finsh />writespeed("/test.bin", 3276800, 1024)
>File write speed: 410880 byte/s
>
>finsh />writespeed("/test.bin", 327680, 1025)
>File write speed: 6680 byte/s
>
>finsh />writespeed("/test.bin", 3276800, 1536)
>File write speed: 459880 byte/s
>
>finsh />writespeed("/test.bin", 327680, 2048)
>File write speed: 436880 byte/s
>
>finsh />writespeed("/test.bin", 327680, 4096)
>File write speed: 485440 byte/s

---

读取速度：
>finsh />readspeed("/test.bin", 255)
>File read speed: 492640 byte/s
>
>finsh />readspeed("/test.bin", 256)
>File read speed: 492640 byte/s
>
>finsh />readspeed("/test.bin", 512)
>File read speed: 530560 byte/s
>
>finsh />readspeed("/test.bin", 513)
>File read speed: 500160 byte/s
>
>finsh />readspeed("/test.bin", 1024)
>File read speed: 574760 byte/s
>
>finsh />readspeed("/test.bin", 2048)
>File read speed: 612360 byte/s
>
>finsh />readspeed("/test.bin", 4096)
>File read speed: 633080 byte/s

---

presto 2012-08-27

这家伙很懒，什么也没写！

4G C10卡上更多测试结果,

```
finsh>>file_test(2048)                                                          
File speed test with 10MB write and read of 2048 bytes a block                  
Writing ... speed 584 kB/s                                                      
Reading ... speed 979 kB/s

finsh>>file_test(1024)                                                          
File speed test with 10MB write and read of 1024 bytes a block                  
Writing ... speed 282 kB/s                                                      
Reading ... speed 718 kB/s

finsh>>file_test(1025)                                                          
File speed test with 10MB write and read of 1025 bytes a block                  
Writing ... speed 68 kB/s                                                       
Reading ... speed 704 kB/s

finsh>>file_test(512)                                                           
File speed test with 10MB write and read of 512 bytes a block                   
Writing ... speed 40 kB/s                                                       
Reading ... speed 765 kB/s

```