The BUFLEN is fixed 5 bytes now, which has to be increased.
A timeout has to be implemented, which is smaller than max_waittime.
If the timeout is triggered, the data received in the buffer so far
should be sent to the host computer which is responsible for generating
a response. Without the timeout the max_waittime of the phone would
expire and it would repeat sending the command, so that we do not
have atomary messages anymore.
