| 摘要 |
PURPOSE:To facilitate the generation of an address of a neighborhood point and to eliminate the need of a complicated control program by generating X and Y addresses corresponding to a relative distance of a point to be accessed and a point which becomes the center in eight neighborhood points or four neighborhood points by a counter and a decoder. CONSTITUTION:An output of a decoder 2 is added to values of an X counter 3 and a Y counter 4 for generating or holding an X address and a Y address of a point which becomes the center by adders 5, 6, respectively, and becomes a logical address of a point to be accessed in eight neighborhood points. Also, the X address is shifted by a shifter 7 so that an overlap to the Y address is eliminated, added to the Y address by an adder 8, and becomes a physical address. In this case, when a neighborhood access decoder formed by joining the counters 3, 4 and the decoder 2 is used, an address of eight neiborhood points can be generated easily by only inputting clock to the counter. In such a way, generation of the address of the neighborhood point is facilitated, and a complicated control program becomes unnecessary. |
