User`s guide

5.2 Infra-red Tunnelling Application
Development of the infra-red tunnelling applications has been difficult for a number of reasons. The
infra-red transceiver used, the Actisys 200L, has limited documentation, and was initially unable to
be used under Windows NT.
The Actisys transceiver came with driver software for Windows 95. The documentation (Actisys
2000) stated that it was unnecessary to install the driver under Windows 98 or Windows 2000
since these versions of Windows already had the driver built in. However, there was no mention
of Windows NT. Information on the Actisys web site stated that separate Windows NT drivers
were required, and that the drivers were available for purchase from Extended Systems (formerly
Counterpoint Systems) (Actisys 2000). The drivers are part of the QuickBeam NT software package.
A version for Windows 95, QuickBeam 95, was also available but was not purchased. QuickBeam
NT was purchased online and installed, and on this basis it was decided that a second infra-red
transceiver should be purchased.
However, when the transceiver was tested with the QuickBeam NT software, no data could be
received from the test source, an Apple Newton MessagePad 130. The Actisys documentation states
that the Actisys 200L transceiver works with Newton MessagePads. The process was tested out on
three PCs, including a notebook, all running Windows NT, with the same results.
The Actisys infra-red transceivers and the QuickBeam software are both certified by IrDA to
be IrDA-compliant. However, the Newton MessagePad uses Sharp’s ASK infra-red technology, not
IrDA, so that although the transceiver can receive signals sent by the Newton, the driver software
cannot interpret them.
The driver was initially installed on a notebook computer running Windows 95. The software
was able to be used without problems. The IRServer and IRClient applications are compatible with
Windows 95, and because they have been built with MFC libraries linked in, they run on Windows 95
without any external libraries. However, since IRServer and IRClient were to be used in conjunction
with the videoconferencing system, which runs on Windows NT, Windows 95 could not be used.
The infra-red driver opens the physical COM port that the infra-red transceiver is connected to,
and send a message requesting the transceiver send data. Without the drivers installed, reading from
the port returns no data, despite infra-red signals being sent to the transceiver. The protocol used
by the transceivers is proprietary, and although it may be possible to decode the protocol, this hasn’t
been achieved. Since the driver opens the COM port, it can’t be used by any other application (a
COM port can be used by only one application at a time). The driver creates a virtual COM port,
as described previously, which is used by applications to communicate with the infra-red device.
The Infrared Monitor control panel (see Figure 14) monitors data coming in through the
transceiver, and displays the status of the infra-red connection — either a device is in range, no
devices are in range, or, on Windows 95 only, “infra-red devices are operating nearby” (interfer-
ence). When the Newton sends infra-red signals to the transceiver, the Infrared Monitor shows this
as interference. Interference can also be caused by many remote controls (e.g. TV and VCRs). The
Windows NT drivers do not show interference, instead displaying the “no devices in range” message
(see Figure 15). Except for this difference, the Windows 95 and Windows NT infra-red drivers, and
the “Infrared Monitor” control panel, look and behave identically.
In conjunction with QuickBeam NT, two Actisys transceivers were able to communicate with each
other, and files could be sent using the QuickBeam software. The name of the PC being connected
to shows up in the Infrared Monitor application where the name of the owner shows up in the case
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