Within 10 minutes I have had my core completely stop after flashing new code on it.
The code is nothing special, reads an analog pin, does a bit math, then sets a pin high/low depending on the read value.
When pressing the flash button it starts flashing cyan, then flashes a bit faster, then stops flashing followed by nothing more at all. Re-connecting power does nothing, reset does nothing, only thing I have found that will bring it back alive is factory reset. But doing that every 3rd time you flash new code quickly become annoying.
I’m not the only one! Mine was doing that last night. I flashed it, it blinked cyan, then goes faster then just stops…nothing but a power light. I had to factory reset mine 3 times last night.
Sorry you ran into the problem, but I’m glad you were able to get things back up and running with a factory reset! We’re still trying to track down and fix this issue. I suspect it’s the result of a copy error introduced when copying the over the air firmware update to the external flash and back, which is why it’s somewhat random. This is also the “rgb led dim / d7 light on” bug. There have been a few other threads about this, including this one: https://community.spark.io/t/spark-core-died/2847/6
The hope is to fix this both by rigging the hardware watchdog to reset the core out of a bad flash, but also to try harder to validate copying to and from the external flash.