00: foo = 01x01x01x
01: foo = 000111xxx
0x: foo = 0xxx1xxxx
11: foo = 000111xxx
1x: foo = 000111xxx
00: foo = 01x01x01x
01: foo = 000111xxx
0x: foo = 0xxx1xxxx
11: foo = 000111xxx
1x: foo = 000111xxx