Mikkel, You don't have to remove the whole U15. You can just give a 3.3V pull-up to the 4th PIN on the J1 connector. Then the board will not be stuck at the UBOOT anymore.
My question is how to fix it from software perspective? In u-Boot source, how can we make sure it is not stuck? If anyone can answer my question, i would really appreciate it. Regards, Shu On Friday, October 31, 2014 12:19:11 PM UTC-5, mi...@mikini.dk wrote: > > > On October 16th 2014 21.26.23 UTC+2 Gerald wrote: >> >> Is the power LED shutoff too? >> Gerald >> > > Hi Gerald. > > I'm also affected by the OP's issue of periodic failing boots on BBB (I > got all REV Bs). > > My experience has always been with the power led lighting up and the > system stuck without booting. Pressing the reset switch takes the system > out of this locked up state, but neither boot switch or power switch has > any effect. > > I am very interested in your input on the successful experiences put > forward by Andrew and Marcus in May, about modifying uboot to remedy noise > input on UART0_RXD (pin E15 of AM3358). > > I have done some tests today documenting the basic issue and some followup > experiments investigating this specific cause, and I would appreciate if > you could take a look and comment on the resulting speculations. You can > find the details here; > http://www.mikini.dk/index.php/2014/10/beaglebone-black-periodic-boot-failure-establishing-failure-rate-and-possible-cause > . > > Executive summary; removing U15 (SN74LVC2G241: UART0 powerdown isolation) > seems to remedy the boot issue on a CircuitCo-produced BBB in my possession. > > Although my result is inconclusive, as I was careless enough to rush > myself into omitting a pre-modification test, verifying the failure rate of > the unmodified BBB. > > > Thanks in advance for your help, and for my Beagle puppies ;). > Mikkel > -- 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 beagleboard+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
