What are the other settings of MSCOMM and what event is catching an input from the scale?

>Dear Experts
>
>I am developing a Weight Bridge Software.
>To get data from Indicator device I use following procedure.
>

>THISFORM.MSCOMM.PORTOPEN=.T.
>Abc=THISFORM.MSCOMM.INPUT
>IF LEN (ALLTRIM(SUBSTR(A,2,8)))>0
>THISFORM.TEXT1.VALUE=VAL(SUBSTR(A,2,8))
>ENDIF
>THISFORM.MSCOMM.PORTOPEN=.F.
>

>That above work fine in VFP6 on Windows98 platform.
>But when I test this procedure in WindowsXP, following situation appears
>
>Abc=THISFORM.MSCOMM.INPUT
>
>In the above line when I put mouse pointer on (THISFORM.MSCOMM.INPUT)
>then it shows following data
>
>30#& 30#& 30#& 30#&
>
>But variable ABC holds nothing, so text1 appears empty.
>My question is: why MSCOMM.INPUT value does to store into variable abc.
>
>Please help