Commander

USB TTY interface intended for use with an Arduino Nano.
A very simple protocol is used to to reduce the byte traffic to the absolute minimum required.
257 symbols are used with byte values 0x00 to 0xFD to send data values 0x00 to 0xFD.
0xFF is used as the start character. Byte pair, 0xFE, 0xFD is used for data value 0xFF and byte pair 0xFE, 0xFE is used for data value 0xFE.
The byte following the start character points to a function which will receive the data and run. A lookup table associates the function pointer with the number of data bytes it requires. Note that a data byte will require one or two symbols.
Only the data bytes are counted, not the symbols required to send them.
A lookup table associates the function pointer with the receiving function.
A Nano C program is included to demonstrate how the protocol is used.