My Rev.A6 BBB had been running solidly 24/7 for months, with only explainable software-related crashes. But in the last week it has just hung twice, with no relation to software functions, nothing unusual in the logs, and D2/3/4 on solid.
It is powered by an analog regulator from my solar house battery system with huge and redundant battery banks, so there is really no chance of a power glitch. It runs the RCN distro of Ubuntu 14.04, from a 16 GB SanDisk uSD. When it hangs and I press Reset without cycling power, I get no user LEDs, but I do get a series of "CCCCC" characters on the console port. My A6 SRM says: --- Without holding the [boot] switch, the board will boot try to boot from the eMMC. If it is empty, then it will try booting from the microSD slot, followed by the serial port, and then the USB port. --- But that is for a power cycle boot. Reset alone, with constant power, "does not change the boot mode". Apparently that means does not change between eMMC default and uSD default for the first try, but still allows for Serial or USB boot if the default local storage fails. Later it says: --- On boot, the processor will look for the SPIO0 port first, then microSD on the MMC0 port, followed by USB0 and UART0. In the event there is no microSD card and the eMMC is empty, USB0 or UART0 could be used as the board source. --- It is not clear whether USB and UART/Serial are checked in a particular order, or are continuously checked. My experience seems to suggest that Serial, at least, is continuously checked, and that uSD is also continuously checked: If I remove the uSD while the "CCCCC" is streaming on the console, nothing obvious happens. If I then re-insert the uSD, booting begins instantly and proceeds normally! So, I'm guessing the uSD somehow loses contact with its socket, and an access from the BBB fails and hangs Linux, with the LED that seems to indicate uSD access on solid. But I can't see any problem inside the uSD socket, and the contacts on the uSD itself look perfect. And this uSD socket has a relatively easy life compared to those in my phone or other portable/remote devices, which have never glitched on me. So what else could this be? An electrical failure inside the uSD card? Guess I should try a power-cycle reboot without mechanical disturbance next time it happens... -- 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.
