| 摘要 |
<p>PURPOSE:To achieve a curtailment of the capacity of a memory for storing a data for conversion and a shortening of dedication time of a CPU for coordinate conversion. CONSTITUTION:A differential data of a sine data and a cosine data between adjacent angles is written into a ROM2 beforehand for each unit angle. Clock generation circuits 10X and 10Y apply clock pulses to counters 11X and 11Y by setting the data for a single latch circuit 6 and the counters 11X and 11Y determine absolute values of the cosine data and the sine data respectively. Multiplier circuits 12X and 12Y add up values of the counters 11X and 11Y at a fixed time interval to determine an X position data and a Y position data for the counters 13X and 13Y respectively. The writing of the sine data and the cosine data as differential data into the ROM2 can curtail the ROM capacity to reduce time required for setting the data read for the latching circuit 6 thereby shortening the dedication time of the CUP1 required for coordinate conversion.</p> |
