EEPROM (Electrically Erasable Programmable Read-Only Memory)，电可擦可编程只读存储器--一种掉电后数据不丢失的存储芯片。简而言之就是你想断电后arduino还要保存一些参数，就使用EEPROM吧。在各型号的arduino控制器上的AVR芯片均带有EEPROM，也有外接的EEPROM芯片，常见arduino控制器的EEPROM大小：Arduino UNO、Arduino duemilanove-m328、Zduino m328均使用ATmega328芯片，EEPROM都为1KArduino duemilanove-m168的EEPROM为512bytesArduino 2560的EEPROM为4K下面我们介绍arduino自带的EEPROM使用方法，arduino的库已经为我们准备好了EEPROM类库，我们要使用得先调用EEPROM.h，然后使用write和read方法，即可操作EEPROM。

另：下面的官方例子由于写成较早，所以讲EEPROM的大小都定为了512字节，实际使用中，大家可参照上面所说的EEPROM大小，自行更改。

1.写入

选择 File>Examples>EEPROM>eeprom_write

/*

* EEPROM Write

*

* Stores values read from analog input 0 into the EEPROM.

* These values will stay in the EEPROM when the board is

* turned off and may be retrieved later by another sketch.

*/

#include <EEPROM.h>

// EEPROM 的当前地址,即你将要写入的地址,这里就是从0开始写

int addr = 0;

void setup()

{

}

void loop()

{

//模拟值读出后是一个0-1024的值，但每字节的大小为0-255，所以这里将值除以4再存储到val

int val = analogRead(0) / 4;

// write the value to the appropriate byte of the EEPROM.

// these values will remain there when the board is

// turned off.

EEPROM.write(addr, val);

// advance to the next address. there are 512 bytes in

// the EEPROM, so go back to 0 when we hit 512.

addr = addr + 1;

if (addr == 512)

addr = 0;

delay(100);

}

2.读取

选择 File>Examples>EEPROM>eeprom_read

/*

* EEPROM Read

*

* Reads the value of each byte of the EEPROM and prints it

* to the computer.

* This example code is in the public domain.

*/

#include <EEPROM.h>

// start reading from the first byte (address 0) of the EEPROM

int address = 0;

byte value;

void setup()

{

// initialize serial and wait for port to open:

Serial.begin(9600);

while (!Serial) {

; // wait for serial port to connect. Needed for Leonardo only

}

}

void loop()

{

// read a byte from the current address of the EEPROM

value = EEPROM.read(address);

Serial.print(address);

Serial.print("\t");

Serial.print(value, DEC);

Serial.println();

// advance to the next address of the EEPROM

address = address + 1;

// there are only 512 bytes of EEPROM, from 0 to 511, so if we're

// on address 512, wrap around to address 0

if (address == 512)

address = 0;

delay(500);

}

3.清除

选择 File>Examples>EEPROM>eeprom_clear清除EEPROM的内容，其实就是把EEPROM中每一个字节写入0，因为只用清一次零，所以整个程序都在setup部分完成。

/* * EEPROM Clear

*

* Sets all of the bytes of the EEPROM to 0.

* This example code is in the public domain.

*/

#include <EEPROM.h>

void setup()

{

// 让EEPROM的512字节内容全部清零

for (int i = 0; i < 512; i++)

EEPROM.write(i, 0);

// 清零工作完成后，将L灯点亮，提示EEPROM清零完成

digitalWrite(13, HIGH);

}

void loop()

{

}