Liu,

Are you sure you have it set to an 8bit setting instead of 7bit?

You can also simply your code to:

mscomm.olemscomm.object.output = chr( strData )

>Use the MSCOMM control
>But It doesn't send binary Data
>
>*This is my SendData function
>
>function SendData(strData)
>dime comout(1)
>store chr(strData) to comout
>mscomm.olemscomm.object.output=comout
>endfunc
>
>Wrong: if strData > 128 and strData < 255 (WIN98 Chinese operating system )
>
>How can I transmit a single byte Hex data?