In this case, the temperature is read by a LM35 temperature sensor and that value, along with the time, is recorded to a .csv file on the SD card in one minute intervals.

Log Temperature Sensor Data to Google Sheet using NodeMCU ESP8266; ... data at every minute will give # Approx Backup time = 30000/1/60/24 = approx 20 days of backup from machine import Pin, I2C from ...