Hi, I'm trying to program eMMC card with STM32U575 but the init fonction MX_SDMMC1_MMC_Init() failes in SDMMC_GetCmdResp3(SDMMC_TypeDef *SDMMCx) and return SDMMC_ERROR_CMD_RSP_TIMEOUT. Any idea?

[TDK]

While that may be true, I can't slow it down by an order of magnitude and see if that fixes the problem.

[j.kouadio]

It doesn't change anything

[Tesla DeLorean]

Not with the U5, but I've done commercial work with them on the F4, L4, F7 and H7 platforms, so I'm reasonably comfortable with the electrical interfacing and driver/file-system side operation of eMMC parts.

Start with the schematic, or relevant section thereof.

If you are confident it is wired properly and functionally sound, start with the software clocking the bus a 25 MHz, or a convenient lower multiple of your primary clock, connect in 1-bit mode, read the Extended CSD from the device, and confirm that's working properly.

[j.kouadio]

I found the solution 3 months ago, sorry for the delay, if you meet the same error, you just have to replace MMC_HIGH_VOLTAGE_RANGE by eMMC_DUAL_VOLTAGE_RANGE for

#define MMC_VOLTAGE_RANGE MMC_HIGH_VOLTAGE_RANGE.

Thanks