Specifications

Remote Control and Receiver-Transceiver Specifications and Requirements

for Windows Media Center in Windows Operating Systems

Device Design Considerations

Considerations for building an emulation device are very similar to considerations when building

an IR receiver device using the port driver model.

Unique Serial Numbers

The software requires each device to have its own serial number. This is implemented using the

USB iSerialNumber string descriptor. The format of this string is not mandated as long as it is

unique to the individual device.

The serial number is necessary for the software to discriminate between multiple identical

devices that are plugged into the same computer.

This serial number does not need to be truly unique as long as it is consistent. This means that

the device could assign a semi-random number to itself the first time it is plugged in as long as it

uses the same number on each subsequent use of the device. This allows the manufacturer to

avoid serialization of serial numbers at device manufacture time.

Emulator Versioning

There are two versions of the emulator protocol. The first version (called

EMVER_EMULATOR_V1 in the code) was added for the Windows Media Center in the release

of Windows Vista. The new version (called EMVER_EMULATOR_V2 in the code) is added for

Windows 7 to correspond with the Consumer IR Version 2 DDI changes to the IR class

driver/port driver model.

An EMVER_EMULATOR_V1 emulator should work correctly with the version 1 DDI and the

version 2 DDI. An EMVER_EMULATOR_V2 should work with the version 2 DDI and should

mostly work with the version 1 DDI. It may expose device capabilities that the version 1 DDI is

unprepared to take advantage of.

It should be assumed that all topics in this section refer to both the EMVER_EMULATOR_V1

interface and the EMVER_EMULATOR_V2 interface unless otherwise specified. If a section only

refers to the EMVER_EMULATOR_V2 interface, it will be labeled ―EMVER_EMULATOR_V2

only‖.

For more information about how the host learns whether the device is EMVER_EMULATOR_V1

or EMVER_EMULATOR_V2, see CMD_GETEMVER and RSP_EQEMVER.

Types of Emulation Devices

For version 1 emulation devices, there are two types of devices that you can build as emulation

devices:

 IR transceiver emulator: a device that can receive IR input from a remote and can transmit IR to

control a set-top box, such as a TV signal cable box or a satellite box.

 IR receiver emulator: a device that can only receive IR input from a remote; it cannot transmit IR

to control a set-top box.

For information about the requirements for providing either transmitter or receive-only

functionality, see sections Input-0007 and Input-0045 of the Windows Logo Program Hardware

Requirements.