Specifications

Remote Control and Receiver-Transceiver Specifications and Requirements
for Windows Media Center in Windows Operating Systems
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If you use a legacy device, this work is included in the Microsoft-provided design.
Not Only RC6 and SMK QP Protocols
The IR receiver that you‘re building needs to receive more than MC RC-6 and the MC QP
protocols. Because the protocol is decoded inside of Microsoft-provided drivers, your receiver
and your port driver don‘t actually need any details about these protocols. The only place you
need to know about these protocols is to implement the wake-from remote function.
Windows Media Center will not be able to logo a receiver that only receives MC RC-6 and MC
QP protocols.
Addressable Remotes
Remote controls need to be addressable. This is useful in situations where there are two
Windows Media Center computers in a room. For instance, one remote can be set to transmit on
channel #1 and the corresponding PC can be set to receive only channel #1. And the other
remote can be set to transmit on channel #2 and the corresponding PC can be set to receive only
channel #2. This was, the #2 remote will never control the #1 PC.
If you use Microsoft-provided IR drivers and the RC-6 protocol, this should not be of concern. If
you are building a HID device or a RF remote, you will need to implement this functionality.
Receive-Only Doesn’t Support Many Scenarios
Because of the proliferation of cable and satellite set-top boxes, the need to IR blasting is
significant. The number of scenarios where a receive-only device is useful is fairly limited. The
additional cost of producing a transmit/receive device may well be worth it considering the
additional scenarios that this feature enabled.
Multiple Receivers on a Single Computer
You should take into account that there may be multiple IR receivers on a single computer. With
IR receivers going into Super IO Chips, becoming integrated in TV tuners, being included inside
PC cases, and with external USB receivers, it is very likely that a given user will have more than
one IR receiver on their computer.
A receiver, such as a HID receiver, which blindly passes HID events to the operating system is
likely to have problems in this area. If you use a legacy device, a port-driver device, or an
emulation device, this is accounted for in the software and will not be a problem.
HID Device Limitations
If you are building a device that is not a legacy device, an emulator device, or a port driver
device, you will face several limitations in the construction of your device. This is because your
device produces HID codes directly without being filtered through our class drivers.
Device Incompatibility
If your HID device is IR, it is probably tied to a single protocol. Because Windows Media Center
uses multiple IR protocols, there are going to be ―Media Center Compatible‖ IR remotes that are