Application and method for rejection of a false data enable signal during vertical blanking periods in a graphics system

摘要

A false DE rejection system is described. DEs are ignored during a programmable vertical lockout period. Internal timing is used during the vertical lockout period to count the number of vertical lines to ignore. The first DE received after the vertical lockout period signifies the start of the next graphics frame. Default video is output during the vertical lockout period. The TCON is synchronized to the start of the graphics frame. A horizontal line length timer measures the timing for the horizontal line length. The horizontal line length timer may also keep a moving average of all of the lines that it has measured. This helps to ensure that the TCON does not get out-of-sync with the input stream during the vertical blanking periods. The DE rejection system includes automatic blanking detection that ignores DEs that occur after the end of a predetermined graphics frame. The vertical lockout does not occur until there has been no DE for an entire line.