DS1307 Real-time Clock

DS1307 Real-time clock လေးကို အသုံးပြုပုံ အကြောင်း ပြောချင်ပါတယ်။ AliExpress က module လေးဝယ်တာ ၁ ဒေါ်လာလောက်ပဲ ပေးရပါတယ်။ AT24C32 ဆိုတဲ့ 32k EEPROM လေးပါ အဆစ် ပါသေးတယ်။

Figure. Setup.

သူ့ရဲ့ schematic circuit ကို အောက်မှာ ပြထားပါတယ်။

Figure. Schematic circuit for the DS1307 module. (From Emartee)

Arduino နဲ့ အဲ့ဒီ RTC module နဲ့ ဆက်သွယ်တာကတော့ တော်တော်ရှင်းပါတယ်။ Power အတွက် ဝါယာ ၂ ချောင်း၊ communication အတွက် ၂ ချောင်းပါပဲ။

Figure. Wire connection.

DS1307 RTC ကို သုံးတဲ့ နမူနာ Using DS107 Real-time clock with Arduino on Github ကို အောက်မှာ ဖော်ပြထားပါတယ်။

#include 
int y,m,d,wd,h,n,s;//year, month, day, week day, hour, minute, second
char* wds[]={"SAT","SUN","MON","TUE","WED","THU","FRI"};
void setup()
{
  Wire.begin();        // join i2c bus (address optional for master)
  Serial.begin(115200);  // start serial for output

  if(0){ //To change settings
    Wire.beginTransmission(0x68); // transmit to device #104
    Wire.write(0x00);//Set address to 0
    Wire.endTransmission();// stop transmitting
    
    Wire.requestFrom(0x68, 7);    // request 7 bytes from slave device #104
    s = Wire.read();//second
    n = Wire.read();//minute
    h = Wire.read();//hour
    wd= Wire.read();//week day
    d = Wire.read();//day
    m = Wire.read();//month
    y = Wire.read();//year

    if(0){ //To set date/time
      s=0x00;
      n=0x26;
      h=0x12;
      wd=0x03;
      d=0x17;
      m=0x05;
      y=0x16;
    }
    
    Wire.beginTransmission(0x68); // transmit to device #104
    Wire.write(0x00);//Set address to 0
    Wire.write(s & 0x7F);//Enable oscillator
    Wire.write(n);//minute
    Wire.write(h & 0x3F);//hour to 25hr mode
    Wire.write(wd);//weekday
    Wire.write(d);//day
    Wire.write(m);//month
    Wire.write(y);//year
    Wire.endTransmission();// stop transmitting
  }
}

void loop()
{
  delay(1000);
  
  Wire.beginTransmission(0x68); // transmit to device #104
  Wire.write(0x00);//Set address to 0
  Wire.endTransmission();// stop transmitting
  
  Wire.requestFrom(0x68, 7);    // request 7 bytes from slave device #104
  s = Wire.read();//second
  n = Wire.read();//minute
  h = Wire.read();//hour
  wd= Wire.read();//week day
  d = Wire.read();//day
  m = Wire.read();//month
  y = Wire.read();//year

  Serial.print(0x20,HEX);
  Serial.print(y,HEX);
  Serial.print("/");
  Serial.print(m,HEX);
  Serial.print("/");
  Serial.print(d,HEX);
  Serial.print(" ");
  Serial.print(h,HEX);
  Serial.print(":");
  Serial.print(n,HEX);
  Serial.print(":");
  Serial.print(s,HEX);
  Serial.print(" ");
  Serial.print(wds[wd%7]);
  Serial.print("\n");
  Serial.print("\n");
}