1.Previous
3.Next

0s or 1s has no transitions in it, making it impossible to know where the data for any particular byte starts. In order to avoid this problem, additional framing bits are added to either end of every byte, typically one bit on either side, known as the "start and stop bits". This guarantees at least one 1-to-0 transition for every byte, more than enough to keep the clocks locked. However, these bits also expand every 8 bits of data (one byte) to 10 bits,

1.Previous
3.Next