# boot from sd card
    bootpart=0:2
    # boot from emmc
    #bootpart=1:2

    bootdir=/boot
    bootfile=zImage
    console=ttyO0,115200n8
    fdtaddr=0x88000000
    fdtfile=am335x-boneblack.dtb
    loadaddr=0x82000000

    # rootfs on sd card
    mmcroot=/dev/mmcblk0p2 ro
    # rootfs on emmc
    #mmcroot=/dev/mmcblk1p2 ro

    mmcrootfstype=ext4 rootwait
    optargs=consoleblank=0
    mmcargs=setenv bootargs console=${console} ${optargs} root=${mmcroot}
    findfdtfile=setenv fdtfile ${fdtfile}
    rootfstype=${mmcrootfstype}
    loadfdt=run findfdtfile; load mmc ${bootpart} ${fdtaddr} ${bootdir}/${fdtfile}
    loadimage=load mmc ${bootpart} ${loadaddr} ${bootdir}/${bootfile}
    uenvcmd=if run loadfdt; then echo Loaded ${fdtfile}; if run loadimage; then run mmcargs; bootz ${loadaddr} - ${fdtaddr}; fi; fi;