hi,
I would guess that with the right code, you might be able
to do a time delayed macro but you have not supply near
enough information to start to make even the wildest of
guesses.
what language in coming in. excell uses vb. you may need
drivers.
what cache/file/table is the incoming data being held.
if you could capture it, what format is the data in.
how are you going to store in in excel.

we are doing something similar where i work. the incomeing
language is in c+. it is sent to an ascii text file
(notepad). we upload it(macro) once a day
the ascii files are saved and dated daily. the excel part
does the summarizing and reporting.
The upload we do is a simple open text file and parce.

-----Original Message-----
I am trying to use excell to track downtime in a
production line and would
like to have the program count everytime a signal is
received from an input
port into the computer.

How do I have excell go outside its environment to look
for that input?
.