From: Gerald Coley <[email protected]> Reply-To: <[email protected]> Date: Wednesday, December 4, 2013 at 4:55 PM To: "[email protected]" <[email protected]> Subject: Re: [beagleboard] How to make BeagleBone black boot off SD card
> Push and hold the boot button and apply power. > > http://www.elinux.org/Beagleboard:BeagleBoneBlack > > Gerald Let me clear something up that seems to be confusing everyone. Gerald is correct from a hardware point of view; however this only selects which u-boot environment is loaded. When the boot button is pressed, the u-boot env is loaded from the SDCard and when the boot button isn¹t pressed, the eMMC u-boot env is loaded. From that point onwards the current u-boot env checks to see if the SDCard is installed and if it is, u-boot boots from the SDCard FAT partition. If the SDCard isn¹t installed, it boots from the eMMC FAT partition. Since the u-boot env is the same on both the SDCard and the eMMC, it doesn¹t matter if the boot button is pressed or not. It is the uEnv.txt file that modifies u-boot env behavior by adding a ³uenvcmd² line. I hope I haven¹t confused everyone. Regards, John > > > > On Wed, Dec 4, 2013 at 3:50 PM, <[email protected]> wrote: >> Good afternoon, >> I don't understand how to determine whether the BBB is booting off the SD >> card or booting off the internal flash. >> Here's what happened, I installed a 4GB image from getting started section >> onto my SD card >> This was the first image here: >> http://beagleboard.org/latest-images >> >> >> Initially I powered on by holding the button next to SD card, It booted and I >> could tell it was not the internal image, because it did not have the demo >> applications. >> >> Next, I tried hitting the reset button to see if it will boot off the SD card >> again, nothing happened and I could not connect to the BBB any more. I >> scanned all ports and it was not available. >> >> I tried resetting and holding down the button again, but it would not boot >> off the SD card. >> >> Only when I take out the SD card the BBB boots into the original >> installation. >> >> Does anyone know what may have caused this? This is a brand new SD card, and >> I doubt I had damaged it by resetting the BBB. >> >> As far as I understand there are 3 booting options, >> 1. There is booting off internal NAND which only has 70mb (or is this only a >> partition >> 2. >> 3. Booting off SD card >> 4. "If using BeagleBone Black and the image is meant to program your on-board >> eMMC, you'll need to wait while the programming occurs. When the flashing is >> complete, all 4 USRx LEDs will be lit solid. This can take up to 45 minutes." >> >> What I don't understand is how to select how the device boots. How can I make >> it boot off the SD card every time? How do I prevent it from writing to the >> NAND? I want to prevent damaging anything by overwriting the NAND and only >> work within an SD Card. >> >> Wouldn't it have been easier to install a jumper to select which memory the >> device boots from? >> >> Thanks, >> -- >> For more options, visit http://beagleboard.org/discuss >> --- >> You received this message because you are subscribed to the Google Groups >> "BeagleBoard" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to [email protected] >> <mailto:beagleboard%[email protected]> . >> For more options, visit https://groups.google.com/groups/opt_out. > > > -- > For more options, visit http://beagleboard.org/discuss > --- > You received this message because you are subscribed to the Google Groups > "BeagleBoard" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > For more options, visit https://groups.google.com/groups/opt_out. -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups "BeagleBoard" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/groups/opt_out.
