Compute Module • Re: Back up OS and flash through eMMC or SD Card

I am sorry. I need some more detail. I am using CM4 with CM4 IO board. The CM4 IO board has SD card slot.

The CM4 itself can either work with eMMC flash or with SD card. This is because both eMMC flash and SD card pins are connected to same data pins of the SoC.

We can boot CM4 (mounted on CM4 IO) through SD card, is that correct ? How about if eMMC also has an OS earlier. In this case CM4 mounted on CM4 IO board will boot through eMMC flash or through SD card.

Statistics: Posted by TommyBills — Mon Jan 19, 2026 5:19 pm

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