I have a black core that has been running since November, returning humidity, temperature, and light values both via variables and publish(), and this morning the google script that monitors it started return “fetch failed”, no publishing is occurring, and curl’ing the device returns timeout. Meanwhile, the code is obviously running, because it flashes a status light and goes into and out of deep sleep, connecting every time. Both the web IDE and the dashboard show the core as online (little blue circle).
When I cycle power the core comes up, connects, and starts flashing my status led as expected, after a while it goes into deep sleep and then recovers on time, connects, and repeats as above. If I try to flash the core from the web it times out. I used dfu-util to reflash my code, minus the deep-sleep mode, and it still behaves as described in the first paragraph (except for deep-sleeping): it’s clearly operating, the web IDE and dashboard show it online, but it appears to be incommunicado. I don’t see anything like this in searches, and am not sure how to proceed at this point.