Design a digital system that multiplies two binary numbers by the repeated addition meth-od.
For example, to multiply 5 x 4. the digital system evaluates the product by adding the multiplicand four times: 5 + 5 + 5 + 5 = 20.
Let the multiplicand be in register RR, the multiplier in register AR. and the product in register PR. An adder circuit adds the contents of BR to PR.
A zero-detection circuit Z checks when AR becomes 0 after each time that it is decremented.