Problem in reading/writing micro SD card through MPC5554 using SPI clock above 3 MHz

[sanaas]

Hi everybody,

I have interfaced a 4 GB class 4 Kingston micro SD card with MPC5554 using SPI. I have implemented FAT32 file system driver on it.
Everything(reading/writing files) works fine when I keep SPI clock at 3 MHz after initialization. With 3 MHz clock I am able to write 1 MB of data in a file in 1 min which is pretty low speed!!
But when I turn to SPI clock above 3 MHz, the SD card does not read/write sectors at all!! All I want to do is to increase this speed of data transfer.
Has any body done such a thing with speed higher than 3 MHz? I would be so grateful if any body could help me in this issue as I have been trying to solve this issue since last so many days but in vain and my FAT32 driver would be of no use in my application with such a low speed.

Thanks,
Sana

 

[blind_man]

Hello,

Can you please post the code for DSPI? The implementation should use DMA transfer. I do not understand to where do you intenend to copy files.