AT24C256 EEPROM 儲存模組/記憶體模組 Arduino 擴充儲存記憶體專用

商品說明

AT24C256 EEPROM 儲存模組/記憶體模組 Arduino 擴充儲存記憶體專用

容量：256K I2C接口 

1. 板載8P晶片座，安裝AT24C256晶片；
2. 排針供電，板載電源指示燈；
3. 板載I2C通訊所需的上拉電阻；
4. 所有管腳均引出並標注，地址輸入和寫保護管腳直接可以跳線設置；
5. PCB板子尺寸：36.5(mm)x12(mm)

發貨清單：AT24C256存儲模組 x 1塊

原廠技術文件 http://playground.arduino.cc/Code/I2CEEPROM

Arduino 範例

/* 
  *  Use the I2C bus with EEPROM 24LC64 
  *  Sketch:    eeprom.pde
  *  
  *  Author: hkhijhe
  *  Date: 01/10/2010
  * 
  *   
  */

  #include <Wire.h> //I2C library



  void i2c_eeprom_write_byte( int deviceaddress, unsigned int eeaddress, byte data ) {
    int rdata = data;
    Wire.beginTransmission(deviceaddress);
    Wire.send((int)(eeaddress >> 8)); // MSB
    Wire.send((int)(eeaddress & 0xFF)); // LSB
    Wire.send(rdata);
    Wire.endTransmission();
  }

  // WARNING: address is a page address, 6-bit end will wrap around
  // also, data can be maximum of about 30 bytes, because the Wire library has a buffer of 32 bytes
  void i2c_eeprom_write_page( int deviceaddress, unsigned int eeaddresspage, byte* data, byte length ) {
    Wire.beginTransmission(deviceaddress);
    Wire.send((int)(eeaddresspage >> 8)); // MSB
    Wire.send((int)(eeaddresspage & 0xFF)); // LSB
    byte c;
    for ( c = 0; c < length; c++)
      Wire.send(data[c]);
    Wire.endTransmission();
  }

  byte i2c_eeprom_read_byte( int deviceaddress, unsigned int eeaddress ) {
    byte rdata = 0xFF;
    Wire.beginTransmission(deviceaddress);
    Wire.send((int)(eeaddress >> 8)); // MSB
    Wire.send((int)(eeaddress & 0xFF)); // LSB
    Wire.endTransmission();
    Wire.requestFrom(deviceaddress,1);
    if (Wire.available()) rdata = Wire.receive();
    return rdata;
  }

  // maybe let's not read more than 30 or 32 bytes at a time!
  void i2c_eeprom_read_buffer( int deviceaddress, unsigned int eeaddress, byte *buffer, int length ) {
    Wire.beginTransmission(deviceaddress);
    Wire.send((int)(eeaddress >> 8)); // MSB
    Wire.send((int)(eeaddress & 0xFF)); // LSB
    Wire.endTransmission();
    Wire.requestFrom(deviceaddress,length);
    int c = 0;
    for ( c = 0; c < length; c++ )
      if (Wire.available()) buffer[c] = Wire.receive();
  }




  void setup() 
  {
    char somedata[] = "this is data from the eeprom"; // data to write
    Wire.begin(); // initialise the connection
    Serial.begin(9600);
    i2c_eeprom_write_page(0x50, 0, (byte *)somedata, sizeof(somedata)); // write to EEPROM 

    delay(10); //add a small delay

    Serial.println("Memory written");
  }

  void loop() 
  {
    int addr=0; //first address
    byte b = i2c_eeprom_read_byte(0x50, 0); // access the first address from the memory

    while (b!=0) 
    {
      Serial.print((char)b); //print content to serial port
      addr++; //increase address
      b = i2c_eeprom_read_byte(0x50, addr); //access an address from the memory
    }
    Serial.println(" ");
    delay(2000);

  }