| 摘要 |
<p>A microcomputer of the present invention comprises a multiplication circuit (101) for multiplication of a multiplier and a multiplicand data, a ripple carry adder (102) for addition of the data and the carry from the multiplication circuit and addition of the multiplication results, a multiplication result holding register (108) to hold the multiplication result obtained by the addition of said data and the carry from the ripple carry adder, a product-sum operation result holding register (109) to hold the product-sum operation result obtained by addition of the multiplication results at the ripple carry adder, a selector (106) to selectively input the data or the carry from the multiplication circuit or the multiplication result held at the multiplication result holding register to the ripple carry adder, another selector (107) to selectively input the data or the carry from the multiplication circuit or the product-sum operation result held at the product-sum operation result holding register to the ripple carry adder and a still another selector (112) to selectively output the multiplication result or the product-sum operation result held at the multiplication result holding register or the product-sum operation result holding register. <IMAGE></p> |
