PURPOSE: To speed up the data operating processing by providing an adjusting control means controlling an operating means and allowing the adjusting control means to output selectively a control signal controlling the operating means based on the relation among the sign of an input data, absolute value of the input data and a reference value.

CONSTITUTION: The sign of the input data is checked and when it is positive, a control voltage 1 is impressed to a terminal (c) and logical 0 is impressed to terminals (a), (b), then an arithmetic circuit 10 subtracts the input data and a dynamic range. When the sign of the input data is negative, logical 1 is fed to the terminal (c) and logical 0 is fed respectively to the terminals (a), (b), then the arithmetic circuit performs addition. Then the result of arithmetic operation is set to an output register 16. When the result of said arithmetic operation set to the output register 16 is positive, logical 1 is fed to an inverter 23 and when negative, logical 0 is fed to the inverter 23. Then the control is conducted in the transfer machine cycle depending on the polarity of the sign of the input data and the polarity of the sign of the output data as the result of arithmetic operation.