Strange setting for writing file into SD Card

Hello everyone,

I'm developing an application which has to save some file to a SD Card.

I'm using the FAT File System in MDK -ARM with a my own board.

At the moment I have some problem writing file into the SD Card.

I read some posts which suggested to drecrease the clock of the MCI peripheral.

I tried to decrease the clock and now I can write files into the SD Card.

The strange thingh is that in order to be able to write files into the SD Card I set the PCLKDIV to 8, but 8 is not a permit value.

Permitted value are 0, 1, 2, 4.

Can someone explain me how it it possible, and what I'm doing wrong?

And how can I decrease the clock of the MCI setting the field CLKDIV of CLOCK register?

Thanks a lot in advance.

Giovanni.