Patent ID: 6711603
Filing Date: 2004-03-23
Classification: G06F

Abstract:
A fractional arithmetic unit for performing fractional arithmetic operations of different numerators and a common denominator with different precisions as required, said fractional arithmetic unit comprising:a denominator calculation unit configured to calculate a denominator from an input value; a numerator calculation unit configured to calculate a numerator from said input value; a floating point conversion unit configured to convert an output of said denominator calculation unit to a floating point value; a reciprocal number calculation unit configured to perform the reciprocal number arithmetic operation configured to obtain a reciprocal number of an output of said floating point conversion unit on a basis of a repetition technique configured to improve a precision of calculation by repeating the operation; and a multiply arithmetic circuit configured to multiply an output of said reciprocal number calculation unit and an output of said numerator calculation unit, wherein said multiply arithmetic circuit is composed of an arithmetic precision judgment unit configured to judge whether or not the output of said reciprocal number calculation unit reaches the precision as required for each of fractional arithmetic operations to be performed; wherein if said arithmetic precision judgment unit makes a judgment as not reaching one of said different precisions corresponding to each of said fractional arithmetic operations, said reciprocal number calculation unit continues repeating the reciprocal number arithmetic operation for said each of said fractional arithmetic operations until the output of said reciprocal number calculation unit reaches said one of said different precisions; and wherein when said one of said different precisions is reached, said multiply arithmetic unit initiates the multiply arithmetic operation and outputs a result of multiplication as an output of said fractional arithmetic operation.