0000 0000 1010 1010
0000 0000 0100 1011
-------------------
0000 0000 0000 1010

0010 1101 1110 1100
0000 0000 0000 1111
-------------------
0000 0000 0000 1100  <-- the value of the first four bits in the top number

freq_interval is one or more of the following:
1 = Sunday
2 = Monday
4 = Tuesday
8 = Wednesday
16 = Thursday
32 = Friday
64 = Saturday

0000 0001 = Sunday
0000 0010 = Monday
0000 0100 = Tuesday
0000 1000 = Wednesday
0001 0000 = Thursday
0010 0000 = Friday
0100 0000 = Saturday