Can I use it for any type of data that supported by Arduino ?
Your example only use : int, char, boolean.
What about “byte” ?
What about array of the same data type (i.e array of bytes) ?

Well , actualy i’m looking of a way to store :
- 3 ip address
- 1 MAC address
- 1 hostname
- 1 port number

Sincerely
-bino-

#include

const byte ROWS = 4; //four rows
const byte COLS = 4; //four columns
char keys[ROWS][COLS] = {
{’1′,’2′,’3′,’A'},
{’4′,’5′,’6′,’B'},
{’7′,’8′,’9′,’C'},
{‘#’,’0′,’*',’D'}
};
byte rowPins[ROWS] = {2,3,4,5}; //connect to the row pinouts of the keypad
byte colPins[COLS] = {6,7,8,9}; //connect to the column pinouts of the keypad

Keypad keypad = Keypad( makeKeymap(keys), rowPins, colPins, ROWS, COLS );
byte ledPin = 13;

boolean blink = false;

void setup(){
Serial.begin(9600);
pinMode(ledPin, OUTPUT); // sets the digital pin as output
digitalWrite(ledPin, HIGH); // sets the LED on
keypad.addEventListener(keypadEvent); //add an event listener for this keypad
}

void loop(){
char key = keypad.getKey();

if (key != NO_KEY) {
Serial.println(key);
}
if (blink){
digitalWrite(ledPin,!digitalRead(ledPin));
delay(100);
}
}

//take care of some special events
void keypadEvent(KeypadEvent key){
switch (keypad.getState()){
case PRESSED:
switch (key){
case ‘#’: digitalWrite(ledPin,!digitalRead(ledPin)); break;
case ‘*’:
digitalWrite(ledPin,!digitalRead(ledPin));
break;
}
break;
case RELEASED:
switch (key){
case ‘*’:
digitalWrite(ledPin,!digitalRead(ledPin));
blink = false;
break;
}
break;
case HOLD:
switch (key){
case ‘*’: blink = true; break;
}
break;
}
}
———————————————————————

So this is a bit tricky because, as I said above, one of the bigger limitations of this technique is that you can’t do dynamic access to the EEPROM using a variable (ie array indexing).

You haven’t said exactly what datatype you want to save, but if it’s a small array (ie 5 integers) then you can load/save the entire array from EEPROM in one hit. This means holding the entire array in RAM, so it won’t work if
it’s a lot of data.

This code compiles but I haven’t tested it: http://gist.github.com/499528

However, if you only need to load/store 5 of the same datatype, and nothing else, then you may really be better off using one of the other techniques described at the top of the post.

Hth.