RTI TheaterTouch T2, User'S Manual And Programming Manual

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TheaterTouch System Controller
66
PULSED IR CODES
This type of transmission does not use a carrier frequency.
Pulsed codes are common in cable TV converter boxes.
HOW THE THEATERTOUCH LEARNS IR CODES
There are many different encoding schemes used for IR codes. The burst and pause
times have fixed lengths, variable lengths, or some combination of the two. To learn
the code, the
TheaterTouch “records” a sample of the code in a manner similar to the
way a tape recorder records sound. Once a sample of the code has been taken, it is
analyzed to find any repeating patterns.
Some codes continuously repeat themselves for as long as the button is pressed.
Others send a code followed by a “keep alive” pattern. Some codes don’t repeat at all.
Any of the above types of codes can also have some sort of preamble in front of them.
It is very important to capture the preamble in this type of code. The IR learning
buffer of the
TheaterTouch is large enough to accommodate the preamble.
When a repeating pattern is found, extra repeats are stripped off before the code is
stored in memory. The number of repeats is also stored so the code can be
reproduced accurately.
If the buffer was filled up during learning, it is assumed that the pattern should be
repeated for as long as the key is pressed. This is common for commands such as
Volume, Balance, and Scan— functions that may need to be continuously repeated.
For these types of commands,
Sustain is set ON as the Edit IR default. If the buffer is
not filled, Sustain is set OFF and the repeat pattern is displayed as the Minimum
Repeats .
The default Minimum Repeats for a code with Sustain ON is one. This means the
repeating pattern will repeat at least one time when the button is pressed. You can
edit this if necessary, in the Edit IR mode of Infrared Library Manager software.
If the code uses a carrier frequency, that frequency is also stored with the code.