| 摘要 |
A digital television system in which digital television signals are received which comprise sequential digital words including a word designating a frame signal, which digital television system comprises a circuit for formatting digital television for use in the system, including a frame sync circuit, a sync word detection circuit for receiving digital television signals from the formatting circuit for monitoring the digital televisions and providing a frame signal output when a word corresponding to the frame signal is detected, a sync confidence counter circuit for receiving the frame signal output from the sync word detection circuit, and adapted when enabled, to be incremented by the receipt of the frame signal and decremente d by the absence of a frame signal, the sync confidence circuit providing a sync lock signal to the formatting circuit when a preset count is reached, and a frame counter circuit for receiving th e digital television signals and providing an enable signal to the sync confidence circuit when a frame count is reached. |
