CM-T43: U-Boot: Creating a bootable SD card
CM-T43 system-on-module uses SPI flash as its main boot storage. In addition to the on-board SPI flash, the CM-T43 can also boot from an SD card. This article describes the preparation and boot process using an SD card.
SD card requirements
The CM-T43 firmware can be written as raw data, or as a set of files in a FAT formatted partition.
- If using the raw data option, make sure that:
- The SD card partitions do not start in the first 1MB of the SD card. Otherwise, the partitions may be overwritten by this procedure.
- If using the filesystem option:
- Format the SD-card with FAT16/32
- Use MBR to store partition data
Installing firmware on an SD card
Installing firmware as raw data
- Insert the SD card into the workstation card reader
- The SD card will be identified as /dev/sdX, where X is the SD card drive letter.
- Run the following command:
dd if=cm-t43-firmware of=/dev/sdX bs=1K seek=320 oflag=dsync
Installing firmware as files in a FAT formatted partition
- Copy the file MLO located in the images folder into the SD-card partition.
- Copy the file u-boot.img located in the images folder into the SD-card partition.
Booting from an SD card
- Plug the SD card into the P9 SD card socket of the SB-SOM-T43
- Hold the ALT.BOOT (SW3) button while resetting/powering on the CM-T43 evaluation system
- The CM-T43 will boot from the SD card