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===== How to Access Ram =====
Each I2C device has an address. The DS1307 chip address is 0x68.

The Ram on the device starts at address 0x08. The first 7 locations are the RTC.\\
{{:rtc_registers.jpg?600|}}

To get to the start of RAM, use the following code:

Wire.beginTransmission(DS1307_ADDRESS);   
     Wire.send(8);	
     Wire.endTransmission();

This will set the I2C address to 0x68, the DS1307 Address.\\
The second line sets the register index to 8, the start of RAM.\\
The third line, Wire.endTransmission(); , transmits the sequence.\\

Subsequent reads from the chip will start at 8. For example, to read 4 bytes from the chip:\\
     Wire.requestFrom(DS1307_ADDRESS, 4);

The above line will put the 4 bytes into the receive buffer. To fetch the bytes:

while(Wire.available())    // slave may send less than requested
     { 
      byte c = Wire.receive(); // receive a byte as character
      Serial.print(c, HEX);         // print the character
      Serial.print(" ");
     }

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