I am looking for some guidance. Where I live we have power failures at least once a week and they can last up to 2 hours.
I have a D1 MINI monitoring the temperature in my fridge with a DHT22 sensor.
The problem is that if the power fails, the Wifi also goes off and my D1 cannot connect to Blynk to show me the actual values of the fridge even if the device is on. It’s powered by a battery and I can see the LED blink when sending data, but it goes nowhere.
Is there a way to save the data to SPIFFS (which I have no idea how to start) and then upload to Blynk, when connected again, in intervals of 5 readings per second? Not sure if SPIFFS is actually the answer I’m looking for.
This data should be then stored on the Superchart at the correct time intervals of the readings, not when uploaded, like filling the missing gaps in the chart.
Any advice will be appreciated.