A method and system for decoding and storing encoded control data
delivered via the horizontal overscan area of a video signal. An
interactive device such as a toy performs behavior defined by control
data that can be encoded into a video signal. The toy is equipped with a
decoder for extracting data from the horizontal overscan portion of the
video signal, and a non-volatile memory that permits the control data to
be stored for use after the video signal is no longer being received. The
control data are delivered as a series of words that include genus codes
and sequence codes. Genus codes identify the specific toy to which the
word is directed, as more than one toy may receive the video signal.
Error grading is used to minimize the effect of such signal
deterioration, so the toy will replace previously received words if newer
words are of higher quality.