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Please refer to the documentation from emtrion (sbc-rzn1d-yocto-manual_v005en.pdf) on how to update the uboot boot loader (u-boot.img). This is possible using a NFS or a TFTP server. The correct version shown should be “U-Boot 2017.01 sbc-rzn1d v01.0xp (Feb 02 2021 - 11:46:11 +0000)”.
Update of the device tree
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