通常情况下我们无需使用外部EEPROM 存储数据，因为 Arduino 本身有自带的。也许是因为这个原因我在网上搜索 Arduino 使用 AT24C02 的资料也很少。
最终在 https://github.com/tardate/Littl ... 4C02/BasicReadWrite 搜索到了一个例子。
先说连接方法：
元件引脚如下：
A0-A2 用于选择设备的地址，如果都为LOW，那么地址是 0x50
WP 是写保护，接HIGH 之后才能进行写入
/*
EEPROM/AT24C02/BasicReadWrite
Basic read/write operations to external EEPROM (AT24C02) with the Wire library
Note: the addressing protocol used here is specific to AT24 models under 16k
For info and circuit diagrams see https://github.com/tardate/Littl ... 4C02/BasicReadWrite
*/
#include <Wire.h>
#define DEVICE_ADDRESS 0x50 // must match AT24C02(A0,A1,A2) wiring
#define MEMORY_ADDRESS 0
byte data;
void setup() {
Serial.begin(115200);
Wire.begin();
data = load_or_init_byte(MEMORY_ADDRESS);
Serial.print("Memory on startup: ");
Serial.println(data, DEC);
}
void loop() {
data++;
store_byte(MEMORY_ADDRESS, data);
Serial.print("Storing: ");
Serial.println(data, DEC);
Serial.print("*Stored: ");
Serial.println(load_byte(MEMORY_ADDRESS), DEC);
delay(1000);
}
byte load_or_init_byte(uint8_t eeaddress) {
byte data = load_byte(eeaddress);
if(data==0xFF) {
data = 0;
store_byte(eeaddress, data);
}
return data;
}
// store +data+ byte at +eeaddress+
void store_byte(uint8_t eeaddress, byte data) {
Wire.beginTransmission(DEVICE_ADDRESS);
Wire.write(eeaddress);
Wire.write(data);
Wire.endTransmission();
delay(20);
}
byte load_byte(uint8_t eeaddress) {
byte data = 0xFF;
Wire.beginTransmission(DEVICE_ADDRESS);
Wire.write(eeaddress);
Wire.endTransmission();
Wire.requestFrom(DEVICE_ADDRESS,1);
if (Wire.available()) data = Wire.read();
return data;
}
