Hi Bernard
The following is the code I use to do the job, but you must have set library to foxtools.fll first and I have not tried it in XP yet. Could you let me know how you got on:

mfPort = "COM2:"
mDialStr = "X"

opencomm = RegFn("OpenComm","CII","I")
writecomm = RegFn("WriteComm","ICI","I")
closecomm = RegFn("CloseComm","I","I")

MComPort = CallFn(opencomm,mfPort,100,100)

=CallFn(writecomm,mComPort,mDialStr,LEN(mDialStr))
WAIT ALLTRIM(mfPort)+" Fired" WINDOW NOWAIT
=CallFn(closecomm,MComPort)

I didn't know there were any other Fox developers in the area. Are you going to the conference in Sydney on the 5th September ?

Cheers
John