Changes
/* Technical */
C Month MSB (0..1) (R/W)
D Leap Year Shift Register (W)
E Stop/Start (0=Stop and set Seconds to 00.0, 1=Start) (W)
F Interrupt (R/W)
Registers 1..C are BCD (range 0..9), a value of 0Fh in these registers indicates Failure (this may happen if the time changed while reading - if that happens, restart reading ALL time registers).
