🌐

IoT Lab content is currently available in Arabic only. We're working on an English version.

Permanent Memory (EEPROM) | NexaLearn IoT Lab | NexaLearn

Data Storage25 دقيقة

Permanent Memory (EEPROM)

Saving settings or temperature readings even after power is disconnected.

Lesson Content

Regular variables are stored in RAM and are lost when Arduino loses power. But EEPROM is a small memory (1 KB in the Uno) that retains its data permanently. You can use it to store the highest recorded temperature, or a button state so it returns to active as soon as power is restored.

Components Needed

Arduino Uno

Wiring Notes

No external components required.

Code Example

#include <EEPROM.h>
void setup() {
  Serial.begin(9600);
  int savedVal = EEPROM.read(0);
  Serial.print("Saved Value: "); Serial.println(savedVal);
  
  // حفظ قيمة جديدة (استخدم هذا بحذر فالـ EEPROM لها عمر افتراضي)
  EEPROM.write(0, savedVal + 1);
}
void loop() {}

Common Mistakes

Placing EEPROM.write() inside a fast loop()! EEPROM can only handle 100,000 write operations — the chip will physically fail within minutes if you write to it continuously.

Next Lesson

Smart LED Strip Control (WS2812B NeoPixel)