Fast approximate logarithm and antilogarithm circuit - is for process control and involves only shift register shifting

摘要

The numbers are held in a register with the position value of each number decreasing from left to right. The exponent is held in two's complement form in a first register section and the mantissa in a directly adjacent second section. The contents of the first section are shifted right one located to overwritethe first location in the second section. The exponent sign bit is placed in the now vacant first section location and the approximate logarithum appears at the register outputs as a fixed point number.