Why would you boot a USB flash thumb drive ? The whole point at least in my own opinion is that a USB HDD is not as write sensitive as flash memory media. Meaning you can write erase, write erase to your hearts content and generally not have to worry that the media may fail. So if you're doing a lot of development naively ( in stead of cross compiling which i prefer ), you will not have to worry about the media failing.
As for the rest, we can sit and quibble about the various technicalities all day long. But in the end, a BIOS, and uboot perform the same duties. On Tue, Jan 7, 2014 at 8:13 PM, liyaoshi <[email protected]> wrote: > Actually , boot from USB ,as slave mode , as I know , iMX5/6 omap3/4/5 all > support boot from usb otg (as slave mode ) > > > 2014/1/8 William Hermans <[email protected]> > >> "So, what is the SD card? It can't just boot off the USB? I believe in >> this case, I am still correct. " >> >> So, what is a BIOS ? If in this case you are correct, then no computer >> system out there can boot off of USB. As all computer devices need to know >> how to bring up the hardware, DDR memory( >> now days ) , and from where to boot. >> >> Ok, so I was wrong, guess you do not care if someone can boot their BBB's >> off of a USB drive. >> >> >> On Tue, Jan 7, 2014 at 7:56 PM, William Hermans <[email protected]>wrote: >> >>> If you actually read the article, you would realize there is no need to >>> modify anything rh_ . . . >>> >>> >>> On Tue, Jan 7, 2014 at 7:56 PM, William Hermans <[email protected]>wrote: >>> >>>> >>>> >>>> On Tue, Jan 7, 2014 at 7:55 PM, William Hermans <[email protected]>wrote: >>>> >>>>> Actually, its loading the kernel from the HDD. Only the uboot files >>>>> need be read, so as the device knows where to boot *from*. >>>>> >>>>> If you want to be a 100% nitpicking techno-junkie, then a purely 100% >>>>> SD/eMMC-less boot can be had by using eprom . . . as it stands, this form >>>>> of USB boot satisfies me, and 99% of the other people out there :) >>>>> >>>>> >>>>> On Tue, Jan 7, 2014 at 7:13 PM, rh_ <[email protected]>wrote: >>>>> >>>>>> On Tue, 7 Jan 2014 16:18:00 -0600 >>>>>> Gerald Coley <[email protected]> wrote: >>>>>> >>>>>> > Correct. It is actually booting form the SD and then loading off the >>>>>> > HDD. The boards cannot boot direct off of USB. They need that >>>>>> > intermediate step. You could also use a large thumb drive like a >>>>>> > 128GB. >>>>>> >>>>>> You are correct those instructions should be modifed to note the >>>>>> reliance on >>>>>> the sd card or eMMC. >>>>>> >>>>>> I recall that the lack of booting straight from USB was designed in >>>>>> but I don't recall what the reason was. Do you know? It's common >>>>>> for devices to boot from USB and I even recall reading USB was checked >>>>>> during the boot process, after SPI (I think). I may have read that >>>>>> in the >>>>>> TRM or is it SRM...? >>>>>> >>>>>> -- >>>>>> 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. >> > > -- > 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.
