sending and receiving protocol

[command, value, B00001010]

command
0: 'ready': first module to sender to say module is ready for getting byte
1: 'send' : message sent from sender to first module
2: 'receive' : message sent from the last module to the receiver

example:

[B00000000, B00000000, B00001010]
then
[B00000001, B10101010, B00001010]
.
.
.
[B00000010, B10101010, B00001010]