Re-enable the eMMC

It seems that the BBB cannot be recognised by the computer (there is no USB device recognised when I plug in the BBB with my computer, and no USB disk showing as well) after I run the following sentence in uEnv.txt:

optargs=capemgr.disable_partno=BB-BONELT-HDMI,BB-BONELT-HDMIN,BB-BONE-EMMC-2G

I haven’t backed up the important data in the system. So I don’t want to simply wipe the eMMC with new images. Do you know how to save the file? They are very important. Thanks.

Right now when I connect the USB cable from the computer to the BBB, the user LEDS, as well as the power LED are lighting up as normal, and after about one minute, only the rightest LED flashes at the heart beat rate. The rest three user LEDs are not showing any light. And I cannot recognize the system (/boot disk) with my computer via USB cable. Help, please.

I could burn a Debian linux image into a SD card, and boot the BBB from that card by holding the boot button. But I failed repairing the eMMC system following the link: http://hipstercircuits.com/unbrick-beaglebone-black-without-erasing-emmc/.

Still won’t boot.

I figured it out myself… I realized that the /dev/mmcblk0p2 is the whole OS root folder, and /dev/mmcblk0p1 is the boot CD folder when you plug the BBB on a computer. Also, I found that there are three folders in /media folder, and the third one “rootfl” is the folder of the eMMC!

So before doing anything further, I simply copied all the useful files from the eMMC to the boot CD folder, shut down, put the SD card back to the computer, and uploaded all the backed up files into my Google drive. Bam! Now I can play with the BBB without any concern…

Then I run the similar sentence referred from the webpage I linked in the last post as follows (of course run the “mkdir /mnt/microSD” and "mount /dev/mmcblk0p2 /mnt/microSD” first):

cp -r /mnt/microSD/lib/modules/3.8.13-bone/ /media/rootfl/lib/modules/

and shutdown, eject the SD card, boot, … It’s back to life again!

Of course, I also deleted the sentence ”optargs=capemgr.disable_partno=BB-BONELT-HDMI,BB-BONELT-HDMIN,BB-BONE-EMMC-2G” in /boot/uEnv.txt…