// This example reads the byte value at address 28 in EEPROM
// memory every second, and sends it over the serial line.
// It then cyclically increments that value by one, and
// writes it to the same address in EEPROM memory.
// After removing the power from the i/o board, counting
// picks up where it left off, because values stored in
// EEPROM memory retain their value when power is lost.

#include <EEPROM.h>          // import eeprom functions

void setup() {
  Serial.begin(9600);        // start serial communication
  Serial.println("Powerup"); // show when the program restarts
}

void loop() {
  byte b = EEPROM.read(28);  // read byte value from eeprom address 28
  Serial.println(b, DEC);    // print that value via the serial port
  b = (b+1) % 256;           // cyclically increment the value
  EEPROM.update(28, b);      // write value to eeprom address 28 only if it changed
  delay(1000);               // waste one second
}