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→Peripheral boot details
Boot sequence can be changed by optional external circuitry implemented on carrier board as described by [[Integration guide (Naon)|Integration guide]].
=== Memory boot details ===
==== MMC Booting ====
When MMC boot option is selected, bootrom looks for a valid boot sector on MMC1.
To properly program a SD/MMC card so it's recognized by bootrom, follow [http://processors.wiki.ti.com/index.php/DM814x_AM387x_PSP_U-Boot#Setting_Up_Boot_Environment_on_SD_Card this] guide from TI wiki.
In brief:
* user should have the first (if more that one is available) partition of MMC formatted as FAT12/16 or FAT32 (partition should also be marked as primary and active)
* inside this partition there should be a file named ''MLO'' which is the U-Boot 1st stage
* with U-Boot 1st stage default option, there should also be a file name ''u-boot'' (which is the second stage) and ''uImage'' (which is the kernel image)
==== NAND Booting ====
{{WorkInProgress}}
=== Peripheral boot details ===
==== UART Booting ====
When UART boot is selected the bootrom output a sequence of <code>CCC</code> characters on serial console (as usual 115200 8N1). While the <code>C</code> are being written, bootrom waits for a [[wikipedia:Xmodem|XMODEM]] transfer to startfor the 1st stage. Once the first stage is downloaded, bootrom execute it and the user should download the second stage via one of the available [[:Category:U-Boot|U-Boot]] command.
Bootrom waits for nearly 3 seconds before timeout the XMODEM transaction and go to the next step in the configured boot sequence.
A detailed explanation of UART booting is available into the [http://processors.wiki.ti.com/index.php/DM814x_AM387x_PSP_U-Boot#U-Boot_UART_support U-Boot] section on TI wiki.
