sterretje:
@Robin2: 80 can not be used as a marker; it indicates that the data relates to the motor;
I allowed myself to be seduced by the statement
The data stream always starts with 80
Then it seems that an adaptation of my 3rd example (recvWithStartEndMarkers() ) might work. Use 80 as the start marker and, rather than use an end-marker, just stop after N bytes have been received.
...R