Can Two 8-bit Adders Be Used to Construct a 16-bit 2's Complement Adder?

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Two 8-bit adders can indeed be used to construct a 16-bit 2's complement adder by connecting them in series. The first adder processes the lower 8 bits of the operands, while the second adder handles the upper 8 bits, taking the carry output from the first adder as its carry input. This setup allows for the correct summation of the two 16-bit 2's complement numbers. The challenge lies in managing the carry between the two adders, which is crucial for accurate results. Overall, this method effectively combines the two adders to achieve the desired functionality.
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16 bit 2's complement adder. Due tomorrow!

You are given two adders. Each adder has two 8-bit operand inputs
and a 1-bit carry input. Each adder calculates the sum of the two
8-bit 2's complement operands and the 1-bit carry and outputs an 8-bit
sum and a 1-bit 2's complement overflow bit. Can you use the two
adders to create a 16-bit 2's complement adder? If so, draw it (represent
the adders as boxes with clearly labeled inputs and outputs). If not,
explain why it is difficult.

Help please
 
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Yes. The drawing and wiring are left as an exercise to the student :-)

HINT:
1) What happens to the 10s place when you add 15 and 27? What happened to the 1s place?
2) What is the purpose of the carry INPUT?
 

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