2025-05-13 1:17 AM
Hi everyone,
I’m working with an STM32H753ZI and trying to interface a 32GB SDHC card via SPI using FatFs.
The SPI connection seems fine (I can read 0xFF repeatedly), but the SD card does not respond to CMD0 or CMD8 — both return 0xFF. As a result, f_mount fails with error code (3).
Test setup:
STM32H753ZI
SPI1 @ 256 prescaler
3.3V SD Card Module (Pzsmocn PZSSD001)
Netac 32GB SDHC card (format is FAT32 )
Observed:
SPI lines work (0xFF received repeatedly).
CMD0 and CMD8 always return 0xFF.
Tried keeping CS low, delaying, reformatting — no change.
Questions:
Is 32GB SDHC over SPI known to have compatibility issues on STM32H753ZI?
Any proven SD cards or modules you recommend?
Any other suggestions to debug this issue?
Thank you for any help or advice!
2025-05-13 4:27 AM
Hello,
>> Is 32GB SDHC over SPI known to have compatibility issues on STM32H753ZI?
No
>> Any other suggestions to debug this issue?
Check the SPI bus with a scope to see what is happening.
You have an "SDCARD over SPI" example in the STM32H7 software package:
under:
Projects\NUCLEO-H743ZI\Applications\FatFS\FatFS_uSD_Standalone
It should be compatible with H753.
Perhhaps you'll have to change the SPI instance and the SPI pins.