2019-11-05 07:18 AM
What is the maximum frequency for SDMMC module when 4-bit mode is used??
2019-11-05 07:42 AM
Depends on a lot of factors, but most microSD cards can have wire clocks in excess of 50 MHz.
On the H7 I think I'm usually clocking the SDMMC module at 200 MHz
2019-11-05 08:10 AM
Actual got data read rates a lot closer to 30 MBps in other testing, this is kind of base-line expectations:
https://community.st.com/s/question/0D50X0000BEYt8MSQT/stm32h743-stm32h7-sdmmc-dma-not-configurable
