/*
ESP32 startup counter example with Preferences library.
This simple example demonstrates using the Preferences library to store how many times
the ESP32 module has booted. The Preferences library is a wrapper around the Non-volatile
storage on ESP32 processor.
created for arduino-esp32 09 Feb 2017
by Martin Sloup (Arcao)
*/#include<Preferences.h>Preferencespreferences;
voidsetup(){Serial.begin(115200);Serial.println();// Open Preferences with my-app namespace. Each application module, library, etc
// has to use a namespace name to prevent key name collisions. We will open storage in
// RW-mode (second parameter has to be false).
// Note: Namespace name is limited to 15 chars.
preferences.begin("my-app",false);// Remove all preferences under the opened namespace
//preferences.clear();
// Or remove the counter key only
//preferences.remove("counter");
// Get the counter value, if the key does not exist, return a default value of 0
// Note: Key name is limited to 15 chars.
unsignedintcounter=preferences.getUInt("counter",0);// Increase counter by 1
counter++;// Print the counter to Serial Monitor
Serial.printf("Current counter value: %u\n",counter);// Store the counter to the Preferences
preferences.putUInt("counter",counter);// Close the Preferences
preferences.end();// Wait 10 seconds
Serial.println("Restarting in 10 seconds...");delay(10000);// Restart ESP
ESP.restart();}