OCROBOT pcf8563是一款设计非常优秀的时间源模块，提供直接可以读取的年月日时间分钟秒，并且可以提供32.768khz 1024hz 1Hz的时钟信号，采用高精度的爱普生晶体，极其优秀的极低功耗。

宽电压范围 1.0~5.5V

复位电压标准值Vlow=0.9V

超低功耗：典型值为 0.25uA (VDD=3.0V,Tamb=25℃)

可编程时钟输出频率为：32.768KHz 、1024Hz 、32Hz 、1Hz

四种报警功能和定时器功能。

rtc_pcf8563.zip

用串口给模块配置时间

/* Demonstration of Rtc_Pcf8563 Set Time. 
 * 时钟时间初始化代码，初始化后时钟会一直运行，以后基本不需要重新初始化了。
 *电路链接
 * VCC to 5V
 * GND to GND
 * SCL to A5
 * SDA to A4
 */ 
#include <Wire.h>
#include <Rtc_Pcf8563.h>
 
//init the real time clock
Rtc_Pcf8563 rtc;
 
 
char data[15];   //（多一位作为结束符存储）
char Str_year[3], Str_month[3], Str_date[3], Str_DoW[3], Str_hour[3], Str_minute[3], Str_second[3];    //字符串时间(多一位作为结束符存储空间)
byte year, month, day, DoW, hour, minute, second;
 
void setup()
{
   Serial.begin(9600);
  //clear out the registers
 
  //set a time to start with.
  //day, weekday, month, century(1=1900, 0=2000), year(0-99)
  Serial.println("Please enter the time: year[2]month[2]date[2]DoW[2]hour[2]minute[2]second[2]");
        Serial.println("example: 2014-12-3 Wednesday 14:15:15 enter:14120303141515");
 
 
}
 
void loop()
{
 
  if (Serial.available() >=14)     //串口读取数据
        {
                for (int a = 0; a <14; a++)
                {
                                data[a] = Serial.read();
                }
                Str_year[0] = data[0];    //拆包
                Str_year[1] = data[1];
                Str_month[0] = data[2];
                Str_month[1] = data[3];
                Str_date[0] = data[4];
                Str_date[1] = data[5];
                Str_DoW[0] = data[6];
                Str_DoW[1] = data[7];
                Str_hour[0] = data[8];
                Str_hour[1] = data[9];
                Str_minute[0] = data[10];
                Str_minute[1] = data[11];
                Str_second[0] = data[12];
                Str_second[1] = data[13];
 
                //Str to byte
                year = atoi(Str_year);    //转换数据类型
                month = atoi(Str_month);
                day = atoi(Str_date);
                DoW = atoi(Str_DoW);
                hour = atoi(Str_hour);
                minute = atoi(Str_minute);
                second = atoi(Str_second);
 
 
                // conf times;    //写入时钟
               rtc.initClock();
               //day, weekday, month, century(1=1900, 0=2000), year(0-99)
                rtc.setDate(day, DoW, month, 0, year);
                 //hr, min, sec
               rtc.setTime(hour, minute, second);        
        }
 
 
  //both format functions call the internal getTime() so that the 
  //formatted strings are at the current time/date.
  Serial.print(rtc.formatTime());
  Serial.print("\r\n");
  Serial.print(rtc.formatDate());
  Serial.print("\r\n");
  delay(1000);
}