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+
+Commands are added to U-Boot by creating a new command structure.
+This is done by first including command.h
+
+Then using the U_BOOT_CMD() macro to fill in a cmd_tbl_t struct.
+
+U_BOOT_CMD(name,maxargs,repeatable,command,"usage","help")
+
+name: is the name of the commad. THIS IS NOT a string.
+maxargs: the maximumn numbers of arguments this function takes
+command: Function pointer (*cmd)(struct cmd_tbl_s *, int, int, char *[]);
+usage: Short description. This is a string
+help: long description. This is a string
+
+
+**** Behinde the scene ******
+
+The structure created is named with a special prefix (__u_boot_cmd_)
+and placed by the linker in a special section.
+
+This makes it possible for the final link to extract all commands
+compiled into any object code and construct a static array so the
+command can be found in an array starting at __u_boot_cmd_start.
+
+If a new board is defined do not forget to define the command section
+by writing in u-boot.lds ($(TOPDIR)/board/boardname/u-boot.lds) these
+3 lines:
+
+ __u_boot_cmd_start = .;
+ .u_boot_cmd : { *(.u_boot_cmd) }
+ __u_boot_cmd_end = .;