eeprom_record.ino

#define SHIFT_DATA 2
#define SHIFT_CLK 3
#define SHIFT_LATCH 4
#define EEPROM_D0 5
#define EEPROM_D7 12
#define WRITE_EN 13

void setAddress(int address, bool outputEnable);
byte readEEPROM(int address);
void writeEEPROM(int address, byte data);
void printContents();

void setAddress(int address, bool outputEnable) 
{
  shiftOut(SHIFT_DATA, SHIFT_CLK, MSBFIRST, (address >> 8) | (outputEnable ? 0x00 : 0x80));
  shiftOut(SHIFT_DATA, SHIFT_CLK, MSBFIRST, address);

  digitalWrite(SHIFT_LATCH, LOW);
  digitalWrite(SHIFT_LATCH, HIGH);
  digitalWrite(SHIFT_LATCH, LOW);
}

byte readEEPROM(int address) 
{
  for (int pin = EEPROM_D0; pin <= EEPROM_D7; pin += 1) {
    pinMode(pin, INPUT);
  }
  setAddress(address, /*outputEnable*/ true);

  byte data = 0;
  for (int pin = EEPROM_D7; pin >= EEPROM_D0; pin -= 1) {
    data = (data << 1) + digitalRead(pin);
  }
  return data;
}

void writeEEPROM(int address, byte data) 
{
  setAddress(address, /*outputEnable*/ false);
  for (int pin = EEPROM_D0; pin <= EEPROM_D7; pin += 1) {
    pinMode(pin, OUTPUT);
  }

  for (int pin = EEPROM_D0; pin <= EEPROM_D7; pin += 1) {
    digitalWrite(pin, data & 1);
    data = data >> 1;
  }
  digitalWrite(WRITE_EN, LOW);
  delay(1);
  digitalWrite(WRITE_EN, HIGH);
  delay(10);
}

void printContents() 
{
  for (int base = 0; base <= 255; base += 16) {
    byte data[16];
    for (int offset = 0; offset <= 15; offset += 1) {
      data[offset] = readEEPROM(base + offset);
    }

    char buf[80];
    sprintf(buf, "%03x:  %02x %02x %02x %02x %02x %02x %02x %02x   %02x %02x %02x %02x %02x %02x %02x %02x",
            base, data[0], data[1], data[2], data[3], data[4], data[5], data[6], data[7],
            data[8], data[9], data[10], data[11], data[12], data[13], data[14], data[15]);

    Serial.println(buf);
  }
}

// 4-bit hex decoder for common anode 7-segment display
byte data[] = { 0xEA, 0xEA, 0xEA, 0xEA, 0xEA, 0xEA, 0xEA, 0xEA, 0xEA, 0xEA, 0xEA, 0xEA, 0xEA, 0xEA, 0xEA, 0xEA };

void eraseEEPROM()
{
  Serial.print("Erasing EEPROM");
  for (int address = 0; address <= 2047; address += 1) {
    writeEEPROM(address, 0xff);

    if (address % 64 == 0) {
      Serial.print(".");
    }
  }
  Serial.println(" done");
}

void setup() 
{
  // put your setup code here, to run once:
  pinMode(SHIFT_DATA, OUTPUT);
  pinMode(SHIFT_CLK, OUTPUT);
  pinMode(SHIFT_LATCH, OUTPUT);
  digitalWrite(WRITE_EN, HIGH);
  pinMode(WRITE_EN, OUTPUT);
  Serial.begin(57600);

  // Erase entire EEPROM
  // eraseEEPROM();


  // Program data bytes
  Serial.print("Programming EEPROM");
  for (int address = 0; address < sizeof(data); address += 1) {
    writeEEPROM(address, data[address]);

    if (address % 64 == 0) {
      Serial.print(".");
    }
  }
  Serial.println(" done");


  // Read and print out the contents of the EERPROM
  Serial.println("Reading EEPROM");
  printContents();
}


void loop() {}