| 摘要 |
PURPOSE:To change the number of lines to be stored only by rewriting a conversion table, by providing a scanning line number conversion part, which converts the value of a scanning counter to a scanning line number, between the scanning counter and a decoder. CONSTITUTION:A scanning line number conversion table is written in a scanning line number converting part 16 on a basis of line control information, which is given from the data processing system at an initialization time, by the control of the generating circuit 17 of a scanning line number conversion table. This conversion table is used to convert the scanning of a scanning counter 11, which is operated cyclically at a constant period, to an optimum scanning system in accordance with the number of lines to be stored and classifications and combinations of communication speeds. In case the lines of communication speeds 2,400BPS, 4,800BPS, and 9,600BPS are mixed, frequencies of scan assignment for a constant period are in proportion 1:2:4, and scan intervals of a specific noticed line are always constant, thereby maximizing the effective processing capability of the device. |
