| 摘要 |
PURPOSE:To reduce the entire compression processing time by obtaining a compression data of a line of a prescribed level not through a compressing circuit. CONSTITUTION:A compressor controller 84 receiving a compression start signal allows code detectors 87, 88 to generate ALL ''0'' code and ALL ''1'' code based on the result of detection by detectros 85 and 86. When ''0'', ''1'' data exist in mixture, the data are transmitted serially one by one bit from an input line buffer 81 to a data compression circuit 82. The compressor controller 84 transmits a compression data outputted from a data compression circuit 82 to a system bus 1 via an output line buffer 83. When the input data are ALL ''0'' and ALL ''1'', the input data are transmitted to the system bus 1 not through the data compressing circuit 82. |
