nixie tube ,RTC and arduino

hi "Arduinoworkers!"
i'm newbie.

My project is to display time (only min and hours!) on 4 nixie tubes using an Arduino and DS1307 for the RTC.

The hardware is on the way (by using 2n2222 for multiplexing the ground,74144 X1 and Appollo DA2100...).
My question is how to read inside the register of the DS1307 and then i need to separate units of minutes and the upper parts of minutes...

ex: For "13 minutes":
DS1307 at 01h (bit 4 to 1 : 1101) i need to have the "3" and then the "1" both in BCD....(13 in BCD 0001 0011)

Does someone got a way?????


Sure, you just do an I2C read from address 0x01.
minutes_ones = address1data & 0x0F; // result is 0-9
minutes_tes = (address1date & 0x70) >>4 ; // result is 0-5