There are plenty of examples on how to use Excel from VBscript out there. Here's one:
http://www.activexperts.com/activmonitor/windowsmanagement/scripts/msoffice/excel/
It looks like ActiveXperts provide a COM object that can be used from VBscript to "talk to" a serial port.
http://www.activexperts.com/activcomport/howto/vbscript/
So, in answer to your question, I'd say "no it's not possible with conventional (read:
out of the box) VBscript."
Cheers,
Trevor Sullivan
http://trevorsullivan.net
