I need to communicate between an embedded system and a Windows computer using
Bluetooth. I've got the embedded end under control, using a Pirani BT-serial
module. My problem is on the Windows end. I want to use a USB-BT module, like
the Linksys USBBT100. The Linksys module presents a virtual COM port for
Windows applications. My Windows application needs to run on an unattended
Windows computer in a factory environment, to receive data from my embedded
system and store it.

To test the feasibility of this approach, I have two computers. One has the
Linksys USB-BT module installed, and it will play the role of the host. The
other computer's serial port is connected to the Pirani module and it stands in
for the embedded system that will eventually be connected to the Pirani.

The good news is that by running a terminal emulator on both computers, I have
been able to establish a link so that anything I type on one terminal emulator
shows up on the other one. The bad news is what I have to go through to get
that link established. The Linksys drivers insist on popping up a dialog box
whenever the BT link is established, asking for user confirmation. This is
unacceptable in an unattended application. The embedded system is a portable
measuring instrument, and it will be turned on and off as needed by the users.
So the BT connection will come and go over the course of a day, and no one will
be present at the host computer to confirm the connection each time.

I have not tried other USB-BT modules, so I don't know if this behavior is
typical. Does anyone know of a USB-BT module that is more appropriate for my

Robert Scott
Ypsilanti, Michigan