2018-09-25 07:00 AM
On this site is stated that the STM32L431CC 48-Pin Package has an SDMMC interface...
https://www.st.com/en/microcontrollers/stm32l431cc.html
But when have a closer look to the HW Manual, the AF functions are only avail at PORT C and PORT D... witch implies that you need an 64-Pin package...
Is it right that I cant use SDMMC interface with the 48-pin package?
And where can find more information / App Notes about the SDMMC interface? Or is it better to use a normal SPI Interface and use SD Card in SPI Mode?
Best regards
Chris
2018-09-25 07:43 AM
It is a general landing page "The STM32L431xx family offers nine packages from 32 to 100-pin packages."
Also seem to recall pin escape issues in packages with less than 64-pins.
SPI should be viable, although depressingly slow.
Some of the EVAL and DISCO board reference schematics are illustrative of the interface. You want short, same length, connections. The D0..D3 and CMD pins should have 33-47K pull-up resistors at the socket.