I bricked the Spark core in my weather station because one cell of the battery died. Its a 4 cell NiCad battery connected to a step up/down converter. The converter delivers 3.3V and works down to 2.3V. Lower voltages means higher current. My assumption is, that the power starting to oscillate when the converter dropped and then the battery recovered and the converter powered up again.
Unfortunately, I can not recover the core anymore. When I supply the core with power it immediately starts breathing in cyan. No green flashing light for connecting to WiFi.
Reseting is also not possible. If I reset to the point where the LED is flashing white (to get to the blue state for setting new Wifi credentials), the core only breath cyan again. Reseting to the yellow state, my PC recognizes a unknown device named DFU CORE.
Can I recover the core somehow?