Infrared & IrDA
ActiveSync Synchronisation Guide CESD-C-0017Applies To:
- Windows CE 2.0, SP1
- Handheld PC Professional, SP1
- Handheld PC 2000
- ActiveSync 3.x
Overview:
Due to the nature of PDA synchronisation. The first step in being
able to synchronise is to establish a hard wired local computer
connection. This can be using a RS323 Serial Cable or in some newer
devices a USB Serial Driver connection.
Both USB and Serial connections can post a number of problems for
users. USB is still often unreliable as the system has to mount
and dismount the driver every time the Handheld PC is connected.
Even more limiting is the fact that USB synchronisation support
exists only on a small number of the Handheld PC devices that exist
out there, is restricted to HPC2000 and above and often is only
available thorough the cradle and not via the device chassis
Serial connections are the universal standard on Handheld PC devices.
Problems can arise especially for users of second hand devices where
serial cables were not included in the purchase. The cables often
make use of preparatory connectors to interface with the device
itself making purchasing a standard replacement from an electrical
store is not an option. Often OEM manufacturers are unable or unwilling
to provide replacements to new users.
Secondly, the Serial RS323 standard is a legacy connection format.
Increasingly PC's are shipping with one or even no COM (Serial)
ports. As demand and necessity wavers for the continued need for
such technologies motherboards without legacy COM and LPT ports
will become the rule rather than the exception.
Infrared or IrDA is a solution that can negate the problems with
the other standards, while providing future proofing to the Handheld
PC host connection while potentially providing additional benefits.
This article discusses the use of Infrared with Microsoft ActiveSync.
More Info:
The infrared technology provides a virtual serial connection between
compatible devices by using Electro Magnetic (EM) pulses in the
Infrared spectrum. There are several different Infrared protocol
specifications. These are
- ASK IR (Amplitude Shift Keyed IR) - 2400 bps (2.4 Kbps)
- IrDA (HPSIR) - 115200 BPS (115.2Kbps)
- Fast IR (FIR) - 4Mbps
- Very Fast IR (VFIR) - 16Mbps
ASK IR should be avoided as it is not compatible with the Windows
CE synchronisation system. FIR and VFIR are not supported by current
generation Handheld PC devices. However the specifications are fully
backwards compatible and in most cases no configuration changes
will be needed.
IrDA operating at 115.2 Kbps is the natively supported specification
of all Windows CE Handheld PC devices. As part of the licensing
requirements all Handheld devices running one of the H/PC platforms
were required to implement the technology.
Communication Protocols
Once the Infrared virtual connection is established there are several
different communication protocols that can operate across the connection.
These are
Dial-up networking (IrCOMM)
IrCOMM allows the Handheld PC to connect to ActiveSync to perform
Synchronisation actions. IrCOMM also provides the connection between
the Handheld PC and an Infrared Cellular Phone when using the
HPC:Factor IrDA Modem driver or others.
Printing (IrLPT)
This is the protocol used when printing to a Windows CE compatible
printer over Infrared.
File Transfer (IrSquirt)
IrSquirt is a Microsoft preparatory protocol for Windows CE devices.
Is used when files are sent Intra-H/PC by Infrared when you send
files to another Windows CE device using Windows CE Explorer.
It is not natively supported on any other Host or PDA platform.
File transfer (IrOBEX)
IrOBEX or IrXfer enables easy file transfer between IrDA devices.
This feature is not natively available on Windows CE. It is often
wrongly assumed that this is how ActiveSync communicates with
the host. Third party software applications are available to provide
IrOBEX support.
Image transfer (IrTran-P)
This is an Infrared implementation found in some Digital Camera
devices. It does not have native support in Windows CE.
Networking (IrNET)
Is a hybrid version of IrCOMM. IrNET allows an infrared device
to act in a similar way to a Network adapter. Using the TCP/IP
protocol it can access a local area network, access shared files
and folders, browse the Internet and so on. It is not natively
supported on the Handheld PC.
Infrared Adapters
There are four main ways that you may encounter Infrared.
- Built in Infrared Port on a Laptop or less commonly a
desktop PC.
- A RS323 extender dongle. This method requires an existing
COM port and a motherboard that can convert the port for use with
an IrDA lamp. The IR lamp will connect to the COM port, and with
setting adjustments in the BIOS will function as a IR device.
This method is very uncommon and usually an optional extra.
- Motherboard Bridge. Similar to the Extender dongle except
that the connector will sit directly on the motherboard. Resource
Addressing space may still make one of the physical COM ports
redundant in many cases. Such facilities are usually an optional
extra from the Motherboard manufacturer.
- USB IrDA. This method provides the greatest level of
future proofing as it removed the dependency on all legacy interfaces.
Using a USB 1.1 or USB 2.0 port the lamp will operate using Plug
& Play. The USB method eliminates potential resource conflicts
and requires no knowledge of advanced Resource Addressing.
For information on configuring or enabling integrated Infrared
or motherboard dependant hardware consult with the manual provided
with your system hardware.
The range and broadcast scope of any given adapter is entirely dependant on
the specific Infrared lamp. In general the device will work up to a range of
5 metres in a 130 degree field of vision from the lamp head. The range can be
affected by ambient temperature as well as supplemental heat and light sources.
It is not affected by or interfere with RF signals emitted from Wireless Network
or radio equipment.
System Requirements
The Infrared protocols are an open standard produced by the Infrared
Data Association (IrDA). The technology is available on most currently
operating systems including Windows, Mac OS and Linux. Synchronisation
is not available using Microsoft solutions for non Windows platforms
and information for non Windows users is beyond the scope of this
article.
Windows 95
Windows 95 RTM and Windows 95a users will require four system updates
to make use of Infrared. The updates should be installed in the
order shown below and before the adapter is enabled.
- Windows Socket 2 Update
- Dial Up Networking 1.4
- IrDA 2.0 Infrared Drivers
- Infrared Transfer 1.0
Download Links for the updates can be found in the HPC:Factor Windows
95 Patching and Updates Guide.
Windows 95 B, C, OEM SR2.0, 2.1 and 2.5 users should install only
the Dial-up Networking 1.4 update.
USB adapters are not supported.
Windows NT 4
Windows NT 4 does not contain any native support for IrDA adapters.
Third party drivers exist however their use and effectiveness is
beyond the scope of this article.
Windows 98, 98SE, Millennium, 2000, XP, 2003
The Operating System contains native functionality for using IrDA
adapters. Drivers for Fast IR or VFIR may be required from Windows
Update or the manufacturers disk.
How-to Guide:
If you are planning to use ActiveSync to sync over IrDA on a new
device which currently does not have a partnership, are using a
new install of ActiveSync or has previously been used to connect
to the system you should run the Get Connected Wizard.
- On the Host PC
- From the File Menu in ActiveSync choose 'Get Connected...'
- On the Handheld PC
- Tap Start and expand Settings
- Open the Control Panel
- Double tap the Communications applet
- Select the PC Connection tab
- Tick to Allow connection with desktop computer when H/PC
is attached and tap Change
- From the drop box Select "' Infrared Port"
- Tap OK twice
- Close the Control Panel
- Return to the Start Menu and open Programs
- Expand Communications and tap to run PC Link
- At the same time you tap PC Link click Next on the Get
Connected Wizard on the Host PC
- Provided the ports are lined up correctly the two devices should
discover one another and establish a new partnership or begin
to sync depending on your circumstance
Troubleshooting
Under some circumstances a connection between a working Handheld
PC and a FIR (USB FIR) device may be unsuccessful. In the event
that you experience problems in connecting your Handheld PC over
IrDA please ensure the following:
- The ports have uninterrupted line of sight and no further than
30cm (12") away from each other
- The Host adapter is in the correct BIOS mode (Integrated adapters
only)
- Clean the lamp lenses using a damp soft cloth free of chemical
solvents. Avoid the use of hot water as it could condense on the
inside of the lens
- Ensure that you haven't enabled Direct Cable Connection access
to your Host PC on the IrDA Virtual COM Port
- Set the maximum permitted baud rate on the host adapter to the
lowest common supported bitrate - 115.2 or lower
- Windows 95 / 98 / Millennium
Open the Control Panel, run the system applet
Click the Device Manager tab
Expand Infrared Devices
Highlight your IrDA adapter and click properties
Windows 2000 / XP / 2003
Open the Control Panel, run the system applet
Open the Hardware Tab
Select Device Manager
Expand Infrared Devices
Double Click on your IrDA adapter
- On the Advanced Tab set the speed limit for the device to
a maximum of 115.2 kbps. If you continue to experience problems
please lower this to 19.2 kbps
- Accept the changes and restart your computer
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