The Problem: The Nano 33 BLE lacks traditional EEPROM. If you need to save user settings (like a volume target or WiFi credentials) that survive a reboot, most guides suggest adding external hardware.
The Solution: The Mbed OS has a built-in file system called KVStore. You can use it to save variables just like EEPROM, but using string "Keys".
The Code:
C++
#include "kvstore_global_api.h"
// Save an Integer void saveSetting(int value) { kv_set("/kv/my_setting", &value, sizeof(value), 0); }
// Load an Integer (with default) int loadSetting(int defaultValue) { int value; if (kv_get("/kv/my_setting", &value, sizeof(value), NULL) == 0) { return value; // Found it! } return defaultValue; // Not found }