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AM335x U-Boot User's Guide
4
USB
In order to boot from the USBmode, set the SW3 switch as follows:
Dip switch # 1 2 3 4 5
Position ON ON OFF ON OFF
UART
In order to boot from the UART mode, set the SW3 switch as follows:
Dip switch # 1 2 3 4 5
Position ON OFF OFF OFF OFF
SD
In order to boot from the SD card, set the SW3 switch as follows:
Dip switch # 1 2 3 4 5
Position ON ON ON OFF ON
CPSW Ethernet
In order to boot from the CPSW ethernet mode, set the SW3 switch as follows:
Dip switch # 1 2 3 4 5 6 7 8
Position ON ON ON ON OFF INDEPENDENT OFF ON
NOTE
The setting of switch SW3:[7:6] is because the EVM uses RGMII mode. For more details please refer to the TRM.
NOTE
Due to heavy pin-muxing, boot device is selectively available on selected AM335x EVMs & profiles. Details about
the availability of the peripherals on different Profiles can be found from the EVM reference manual
[6]
.
Flashing U-Boot with CCS
NOTE
Both the stages of U-Boot need to be flashed on the same media.
The tools are provided in the PSP release to write SPL & U-Boot on to the NAND flash(for NAND boot)
Refer to AM335x Flashing Tools Guide wiki page for instructions on how to flash the pre-built (or compiled) binary
to NAND flash (or the recompiled one) with the help of the NAND flash writer.
After flashing the 2 stages, make sure boot mode is set to NAND and power on the board.