Description

Indian Institute of Technology Kharagpur
COMPUTER SCIENCE AND ENGINEERING
Computer Organization Laboratory
Assignment-2: Verilog Design of Binary Adders
Full Marks: 20
Time allowed: 6 hours
INSTRUCTIONS: Make one submission per group in the form of a single zipped folder containing your Verilog source code files(s) and Verilog testbench(es) only, and not the auxiliary files that Vivado generates. Name your submitted zipped folder as Assgn 2 Grp <Group no>.zip and (e.g. Assgn 2 Grp 25.zip). Inside each submitted source and testbench files, there should be a clear header describing the assignment no., problem no., semester, group no., and names of group members. Liberally comment your code to improve its comprehensibility.
1. [Ripple Carry Binary Adder] Design (using Verilog), simulate, and synthesize for any target FPGA supported by your version of Vivado an 8-bit ripple carry adder. Your design should consist of a cascade of eight full adders. Write a testbench to simulate it. After logic synthesis, note its hardware requirement and critical path delay from the synthesis report. The interface of your design should be:
module ripple carry adder (input [7:0] a, input [7:0] b, input cin, output [7:0] sum,
output cout);. (5 marks)
2. [Hybrid Binary Adder] Design (using Verilog), simulate, and synthesize for any target FPGA supported by your version of Vivado, an 8-bit hybrid adder. Your design should consist of a cascade of two 4-bit carry lookahead adders. Write a testbench to simulate it. After logic synthesis, note its hardware requirement and critical path delay from the synthesis report. The interface of your design should be:
module hybrid adder (input [7:0] a, input [7:0] b, input cin, output [7:0] sum, output
cout);. (6 marks)
3. [Bit-serial Binary Adder] Design (using Verilog), simulate and synthesize for any target FPGA supported by your version of Vivado, a bit-serial adder. Write a testbench to simulate it. After logic synthesis, note its hardware requirement and critical path delay from the synthesis report. The input-side shift registers used in the datpath of your bit-serial adder should have “parallel load” capabilities such that the 8-bit operands can be loaded in each of them in one clock cycle. Come up with a proper interface of your design, which includes all input control signals and a clock signal. (7 marks)
4. Finally, submit a small 1-page report (in .pdf format) comparing the speed of operation and hardware requirements of the above three designs. This report should be inside the zipped folder you submit. (2 marks)