11:45 Low lost communication with its emerald boards around 11:00.
rebooted Rebooted low and everything back up.
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Those were the only messages before the reboot, and they occurred at least 23 hours earlier, which means the problem is not due to a kernel oops, or any other atypical event that the kernel could detect. It is just the good ol' situation where there seems to be a very small but finite possibly possibility that a PC104 interrupt can be missed, and not retriggered, even though the PC104 IRQ interrupt line is high, such that the interrupt handler is never again called.
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| Code Block | ||
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root@low root# irqs Counting interrupts over 5 seconds ... IRQ Interrupt Type Total Int Int/sec ------------------------------------------------------ 3: ISA serial: 1376 275.2 24: GPIO-l eth0: 62 12.4 25: GPIO-l GPIO1-PC104: 1376 275.2 36: SC serial: 15 3 37: SC serial: 101 20.2 42: SC ost0: 509 101.8 114: GPIO isp116x-hcd:usb1: 90 18 115: GPIO serial: 228 45.6 116: GPIO serial: 102 20.4 |