Specifications

Remote Control and Receiver-Transceiver Specifications and Requirements

for Windows Media Center in Windows Operating Systems

 IR Learning. If Windows Media Center is unable to identify the user‘s remote control using

Parse-and-Match, then the user needs to go through the IR learning process. In IR learning,

Windows Media Center captures the RLC for each keypress and stores it in a database.

Windows Media Center needs at least two samples of each key to complete IR learning.

Windows Media Center also needs to measure the carrier frequency for the remote control.

Note Windows Media Center does not support learning toggle bit remotes.

Long-Range Receivers and Wide-Band Receivers

Windows Media Center IR receivers need to have two different light-detecting components. One

of them (long-range) is used most of the time. The other one (wide-band) is only used for IR

Learning.

Long Range Receiver:

 BPF, AGC, and demodulator inside receiver hardware.

 Receive IR Data at 10 meters on center of receiver and 5 meters off center at a distance of 10

meters.

 Returns IR waveform envelope to software for software decoding of IR signal.

 Used for normal day-to-day operation and also for one-time setup of STB control.

Learning Receiver:

 Returns modulated signal to hardware so hardware or port driver can measure carrier frequency.

 Optimized for a distance of 5 centimeters.

 Returns IR waveform envelope to software for software decoding of IR signal.

 Used only for one-time setup of STB control.

Sleep (formally Power) Key Wake

Windows Media Center IR receivers need to support remote wake using a Sleep key on the

remote control. This means that, if the PC is in a low power state, the user can use the Sleep or

Wake button on the remote control to bring the PC into a higher power state. This is a

requirement for all Windows Media Center IR receivers.

The Remote Control Functionality Needed

When designing a system, you have multiple choices about the level of remote control

functionality that you can provide to users. This decision will be based on the type of PC that is

being built, the peripherals that are being distributed with the PC, the country/region that the PC

is being distributed in, and the level of functionality desired by the system designers.

Transmit/Receive Devices

Transmit/Receive devices provide the full set of IR functionality for users. They are able to

receive IR input from a remote control and they provide Power Key Wake functionality for the

users. In addition to this, they provide IR learning, remote identification using parse-and-match,

and IR emitting functionality to control set-top boxes. In many countries or regions, a

transmit/receive device is required for most Windows Media Center systems.

Transmit/Receive devices are required when the following three conditions are true: