| 摘要 |
PURPOSE:To detect an abnormal state rapidly when this device is used for a monitoring system, by displaying a marker under the reception line of a reception-side monitor by writing a specific luminance or chrominance signal in a picture memory at the reception side equivalent to the next line following a transmitted line. CONSTITUTION:On the completion of the writing of line picture data, data write end signal generating circuit 11 is operated by the value of address register 3 and the output of column counter 6. On the other hand, presetting circuit 10 presets the value of the line following a written line in row counter 5. Then, clock change-over circuit 9 switches to supply a high-speed clock to column counter 6; and the output value of data register 4 is specified (e.g. 0) and in the line following the line where line-in picture data is written, the specific value is written at a high speed. |
