SDC default clock speed for STM32F4

[hazelnusse]

I have a Olimex STM32-H407 dev board which has an STM32F407 chip on it. I'm using the SD card and FatFS to write data to the card. I have been search the source tree but am unable to find out what the SDIO clock speed (SDIO_CK in RM0090) is set to by default. My reading of the documentation is that it can be between 0-25MHz. Anybody know what speed it is set to?

Thanks,
Luke

[Giovanni]

Hi,

Look into sdc_lld.h at line 139 and following, the clock is calculated there depending on the device and system clock.

Giovanni

[talsit]

If you have excel, you can try out this clock config tool:
http://www.st.com/web/catalog/tools/FM1 ... 3/PF257927
It will tell you the speed of your SDIO bus.