POSITION DETECTOR CIRCUIT FOR GRAPHIC COORDINATE SYSTEM

摘要

PURPOSE:To provide a position detector circuit for a graphic coordinate system that can carry out the repetitive subtraction of the numbers that cannot be expressed in 2N at a high speed and can simply deal with the subtraction of any type of numbers. CONSTITUTION:A subtractor circuit 7 is used for a detector circuit which detects an object position of a graphic coordinate system. This circuit 7 consists of an adder 11 consisting of the number of bits necessary for expression of a minuend out of those numbers of bits necessary for expression of the graphic coordinate system and an asynchronizing counter 12 consisting of the remaining number of bits. Then the number of higher order bits necessary for expression of the graphic coordinate system are replaced by the counter 12. Thus a function equal to that attained with use of a full-bit adder is secured and at the same time the position of the graphic coordinate system can be detected at a high speed.