Append a 'bsend' command to the script. The set value of this
object should be the exact binary data in hex format to be sent
on the port opened with the 'open' command. The 'bsend ' characters
will be automatically appended. Also a 'null terminator' (\0)
will be automatically appended. The null terminator and the 'bsend '
characters will be counted as characters in the script.