Specifications

Remote Control and Receiver-Transceiver Specifications and Requirements
for Windows Media Center in Windows Operating Systems
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 The system is a desktop system.
 The system includes a tuner.
 The tuner is capable of supporting set-top boxes. This depends on the video standard used and
situation in the country/region where the system is being distributed to.
Transmit/Receive devices are allowed, but not required in other situations, such as laptop
systems, and systems without a tuner device unless a remote is distributed with the system, then
receivers are required.
Receive-Only Devices
Receive-only devices are devices that accept input from a remote control and are able to wake
on the Sleep key, but are unable to do IR emitting. Because of the more limited set of
functionality, receive-only devices are cheaper to produce, but they are also only able to
distribute in a limited subset of PC systems.
Receive-only devices are useful when remote input functionality is desired, but the three
conditions above don‘t require a transmit/receive devices. This includes, but is not limited to,
these three common examples:
 Laptop systems.
 Systems without a tuner.
Receive-only devices can be IR based or RF based.
How Should You Build Your Device
After you decide what functionality your receiver needs, you will need to decide what hardware
and software architecture to use when building your device. This decision should be based
mostly on cost and risk, but can also be based on the level of functionality required.
Legacy Devices - Beanbag/Snowball/Snowflake
Before Windows Vista, legacy devices were the only option for building IR hardware. Microsoft
provided the hardware reference designs, the firmware, and the software drivers. ODMs are
required to use all of these and to follow the designs exactly. Because the design work is done
and the software is provided, this has the cheapest design cost for ODMs. This also makes this
the least risky option. However, because ODMs need to follow designs exactly, the BOM cost for
this is fixed and moderately high. Legacy devices are the only option if OEMs are building
systems that run Windows XP.
To build a legacy device, ODMs need to acquire the device schematic from Microsoft and build
the device following the schematic and BOM requirements. Testing the hardware is possible
using the drivers provided with Windows XP Media Center Edition and later versions of Windows
operating systems with Media Center. The software for legacy devices is distributed with
Windows XP Media Center Edition and later versions of the Windows operating system with
Media Center so no additional software download/install is necessary for customers.
Legacy Device Summary
Design Cost
Low
BOM Cost
High
Risk
Low