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→Boot Options
== Boot Options ==
AM335x processor provides several boot sequences selectable via BTMODE[15:0] bootstrap pins. In order to fully understand how boot works on Diva platform, please refer to chapter 26 ("Initialization") of the [httphttps://www.ti.com/litvlit/ug/spruh73p/spruh73p.pdf/spruh73g AM335x Technical Reference Manual].
SYSBOOT[15:0] terminals are respectively LCD_DATA[15:0] inputs, latched on the rising edge of PWRONRSTn. The booting device list is created based on the SYSBOOT pins. A booting device can be a memory booting device (soldered flash memory or temporarily booting device like memory card) or a peripheral interface connected to a host. The main loop of the booting procedure goes through the booting device list and tries to search for an image from the currently selected booting device. This loop is exited if a valid booting image is found and successfully executed or upon watchdog expiration. The memory booting procedure is executed when the booting device type is one of NOR, NAND, MMC or SPI-EEPROM. The peripheral booting is executed when the booting device type is Ethernet, USB or UART.
