What is the cycle time for the circuit you designed in 4.5.1? How long does it take to perform the 32-bit operation?

Problem 4.5.1

Design a circuit with 1-bit data inputs and a 1-bit data output that accomplishes this operation serially, starting with the least-significant bit. In a serial implementation, the circuit is processing input operands bit by bit, generating output bits one by one. For example, a serial AND circuit is simply an AND gate; in cycle N we give it the Nth bit from each of the operands and we get the Nth bit of the result. In addition to data inputs, the circuit has a Clk (clock) input and a "Start" input that is set to 1 only in the very first cycle of the operation. In your design, you can use D Flip-Flops and NOT, AND, OR, and XOR gates.

In the rest of this exercise, we assume that the following basic digital logic elements are available, and that their latency and cost are as follows:

The time given for a D-element is its setup time. The data input of a lip-lop must have the correct value one setup-time before the clock edge (end of clock cycle) that stores that value into the lip-lop.

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a. b. NOT AND Latency Cost Latency Cost Latency Cost 10ps 2 12ps 4 50ps 1 90ps 2 12ps 100ps 4 OR 2 XOR Latency Cost 14ps 120ps 6 3 D-Element Latency Cost 30ps 10 160ps 2