Cannot get BBB to flash new OS image

Sorry if this is answered somewhere, I looked around and couldn’t find anything on it in this forum.

Someone gave me a BBB to play with, it has Debian 7.x on it, I would like to upgrade it to the latest OS image.

I went to this page ( and am following the instructions.

I downloaded an image onto my macbook from this page - I chose Debian 9.2 2017-10-10 4GB SD IoT .

I used Etcher to burn the image onto a microSD card.

I inserted the card into the slot on the BBB, held down the User Boot button, inserted the power cord, waited until the four LEDs went off, then let go of the button.

No joy. I was only booting from the microSD card, not flashing the image into the eMMC.

I tried to follow the directions to convert the image to a “flasher”. The file that I am supposed to modify (/boot/uEnv.txt) was not in the specified directory. However, I did find it in the /boot/uboot folder. However when I edited it, the line that was I was supposed to uncomment was not there. The script that the non-existent line was supposed to run (cmdline=init=/opt/scripts/tools/eMMC/ also is nowhere to be found.

The system boots just fine from the microSD card, so i think the image on there is ok.

So… what do I try next?

Hold the boot button, the button closest to the sd card, down while applying power until all four USER leds are on. The button is small, so be careful.
The uEnv.txt file should be on the sd card not your BBB. You can boot your BBB without the sd card, inster the sd card, mount the sd card, edit the /boot/uEnv.txt on the sd card. unmount the sd card. power down the BBB. Insert power while holding the boot button down, wait until all 4 USER leds are on (only several seconds). If you have a debug cable, see SRM section 5.12, you can see what is going on.

I’m trying to upgrade my old BBB-A5B to the latest Debian as well. I’m not planning to use emmc.

At the moment I’m always required to press “s2-user boot” button during power up (physical plugin in the cable during the process) in order to boot from microSD with the latest versions. If I use the old image “bone-debian-8.3-lxqt-4gb-armhf-2016-01-24-4gb.img”, the SD boots correctly without the need to use the s2 button every time there is a power interruption or shutdown command (reboot works).

Starting without SD card also works fine (Angstrom).

With the current Debian 9.1 on SD 3 leds light up (0-3) and stay on without blinking (more than 6h tested). Same with Debian 8.7, 9.2.


Can you help me by confirming that you got the same issue booting from SD – Debian 9.1 or 9.2 without pressing “s2 - user boot” button when you plug the power cable in. Perhaps it’s a malfunction in my BBB almost 2 years up and running.

So erase the eMMC, it's getting in the way of the microSD booting..


Long story short.

When the eMMC has the first, and second stage bootloader installed on it. The board will always load these from the eMMC, and then load the rest from the sdcard when one is inserted.

The result is that one can be put into a non working state, because there would be a MLO / uboot / kernel conflict.

There are two ways to solve this, Robert already mentioned one. The other would be to press, and continue to hold the boot button on the board so that it loads MLO, and uboot form teh sdcard instead. I’ve heard mention of some people having difficulties with this, and instead short the boot button. BUt I’ve not done that personally.

In the end, it would probably be easier to do as Robert suggests above.

Thanks Robert & William,

I also prefer erasing eMMC before soldering a switch to replace user boot button.

Thanks for clarifying that eMMC is always the first and SD never overrides eMMC as I wrongfully assumed.

No reason to even solder, worse case you stick a wire bettween two
pins on the expansion header (the push button is routed to a pin on
the expansion header)..