That is not an AWK question. AWK either reads from standard input or from a file you specify on the command line. You can reference a serial port both ways.<br>
Awk will close out as soon as it sees eof though, so a serial port without data on it will cause awk to prematurely close.<br>
You might be able to get around the lack of constant data on a serial port by using a construct like this:<br>
tail -f /dev/ttyXX ¦ awk -f "myawkscript"<br>
since tail will leave the pipe open even if nothing is on /dev/ttyXX, which represents your serial port device.