Patent Number: 6,167,420

Title: Multiplication method and multiplication circuit

Abstract: A multiplication method and a multiplication circuit, wherein a multiplicand is multiplied by a multiplier by using a multiplication means, the result of the multiplication is added by an addition means to a rounding signal to be output from a rounding signal generation means, and the result of the addition, i.e., a multiplication result obtained after rounding, is stored in a register. By a barrel shifter, the multiplication result obtained after rounding stored in the register is shifted by a bit count indicated by a shift bit count signal. The shift bit count signal output from an instruction control means is input to the barrel shifter and a rounding signal generation means. The rounding signal generation means generates a rounding signal on the basis of the shift bit count signal indicating the bit count used to shift the multiplication result after rounding. By carrying out a rounding process in the addition means by using the rounding signal, the rounding process can be carried out at an appropriate position desired by the user.

Inventors: Saishi; Mana (Fukuoka, JP), Kurohmaru; Shunichi (Fukuoka, JP)

Assignee: Matsushita Electric Industrial Co., Ltd.

International Classification: G06F 5/01 (20060101); G06F 7/48 (20060101); G06F 7/52 (20060101); G06F 007/52 ()

Expiration Date: 12/26/2017