Sdystem for transmitting and decoding biphase data, in particular for VPS

A system for decoding biphase coded data inserted in the vertical blanking interval of a video signal, comprising:

• an input for receiving said video signal and said biphase coded data;
• a data separating stage for separating said biphase coded data from said video signal without field or line windowing;
• a timing stage for generating timing signals;
• a start code detection stage for identifying a particular start code, said start code detection stage being coupled to said data separating stage and to said timing stage for receiving data and timing signals therefrom respectively;
• an anticoincidence detector for detecting errors in said biphase coded data, said anticoincidence detector being coupled to said data separating stage and to said timing stage for receiving data and timing signals therefrom respectively, said anticoincidence detector generating an error detection signal in the presence of said errors;
• a logic stage coupled to said start code detector stage, to said anticoincidence detector stage, and to said timing stage for receiving signals therefrom, and generating a control signal in the absence said error detection signals generated during a period beginning with detection of said particular start code of data in a given video line and ending when said timing signals indicate reception of the last data bit of said video line;
• a buffer memory for temporary storage of said biphase coded data, said buffer memory being coupled to said data separating stage and to said timing stage for receiving data and timing signals therefrom respectively, said buffer memory transferring said data to an output in response to said control signal;
• and
• memory means for receiving said data from said output of said buffer memory.

A system for decoding data transmitted in groups with a video signal, comprising:

• a data separating stage receiving said video signal and said data, for separating said data from said video signal without windowing;
• a start code detection stage coupled to said data separating stage for identifying a particular start code of said data and generating a first control code in response thereto;
• a detector coupled to said data separating stage for detecting errors in said data and generating an error detection signal in response thereto;
• a logic stage coupled to said start code detector stage for receiving said first control code, and to said detector stage for receiving said error detection signal, and generating a second control signal in the absence of said error detection signals generated during a period beginning with detection of said start code of a group and ending with reception of the last data bit of said group;
• a buffer memory coupled to said data separating stage for receiving data, said buffer memory transferring said data to an output in response to said second control signal;
• and
• memory means for receiving said data from said output of said buffer memory .