Specifications

Remote Control and Receiver-Transceiver Specifications and Requirements
for Windows Media Center in Windows Operating Systems
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Bootloader
This section contains startup code, comm code, and the bootloader command switch. It has a
checksum as the last 4 bytes which is checked at startup.
Main
This section contains IR reception code, as well as system and IR command switches. The main
code is flash-upgradeable by the bootloader. It has a checksum as the last 4 bytes which is
checked at startup.
Config
This section contains the unique serial number for the device, all strings, and all USB descriptors.
It can be stored either in eeprom or in flash memory.
Sleep Key
This section contains firmware that runs under low power and watches for the Sleep key IR
pattern. It should be flash upgradeable.
Port Driver Requirements
Windows Media Center uses infrared (IR) both for basic control of the computer and for
controlling other IR-based devices used in conjunction with Windows Media Center. It's important
that you have a basic understanding of the IR functionality in Windows Media Center and how it
is used in conjunction with the software so that when you develop your hardware and port drivers
you understand how the hardware and software will work together.
Following are some important terms to know when reading this section:
Main IR Receiver
Wide-band IR receiver used to receive IR commands from the Windows Media Center remote
control and to translate those signals in order to interact with Windows Media Center.
Used in first run when the user is configuring a set-top box. The main IR receiver is used with the
parse-and-match functionality to recognize a set-top box remote control.
Learning IR Receiver
Used in first run when the user is configuring a set-top box. The Learning IR Receiver is a close-
range IR receiver that is used when Windows Media Center is unable to correctly identify the set-
top box remote control using parse-and-match. The user is then guided through a step-by-step
process so that Windows Media Center "learns" the numeric keys on the remote control so it can
control the set-top box.
IR Output
Used to send IR signals from the computer to control a set-top box. The IR signals sent through
the IR output port are sent either from a licensed IR database or from a user IR database, if the
user has gone through the IR learning process.
IR output is important for any customer trying to control a set-top box. There are two primary
scenarios that are important to Windows Media Center:
 The user wants to record a show when they are not at home. Windows Media Center needs
to be capable of changing the channel for the user.