Digital Logic

Question

Please elaborate your answer. 

Comments

We can do all three operations.

By applying K =1 we can do subtraction (C0 = 0, then 1's compliment and C0 =1 then 2's compliment)

By appying K = 0 we can do addition and infact by keeping B =0, and C0 =1 we can do A+1.

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you can't do A+1.

it is mentioned in qsn by "suitably setting control lines K and C₀ only",

you are not allowed to alter or take values of A and B from your side.

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C₀ is 0

K=0, it acts as a 2-bit adder

K=1, it acts like a 1's complement addition

C₁ is 1

K=0, it acts as A+B+1

K=1, it acts as a 2's complement addition

Correct?