Character counting
The simplest method for framing is to use a field in the frame header to store the number of characters in the frame
When the receiver senses an incoming frame it simply checks this field for the number of characters and then counts forward that number to find the end of the frame
5 1 2 3 4 5 6 7 8 9 8 0 1 2 3 4 5 6 8 7 8 9 0 1 2 3