Consider two 4-bit binary numbers A and B. Bits of A are a3, a2, a1, and a0, and bits of B are b3, b2, b1, and b0. A is greater than B if a3 is 1 and b3 is 0, but if a3 and b3 are the same, then if a2 is 1 and b2 is 0, we can determine that A is greater than B. This evaluation continues until a0 and b0 are considered. If a0 and b0 are equal then A and B are equal. Using discrete gates and Verilog gate primitives build a 4-bit comparator that generates a 1 on its GT output when its 4-bit input A is greater than its B input, and a 1 on its EQ output when A and B are equal. Use the generate statement and other Verilog iterative logic support structures.
时间: 2023-12-23 16:06:31 浏览: 12
Here's a possible solution using Verilog:
```
module comparator(A, B, GT, EQ);
input [3:0] A, B;
output GT, EQ;
// generate statement for creating 4 comparator blocks
genvar i;
generate
for (i = 0; i < 4; i++) begin
assign GT[i] = (A[i] == 1) && (B[i] == 0) && !EQ;
assign EQ = (A[i] == B[i]) && EQ;
end
endgenerate
endmodule
```
In this solution, we use a `generate` statement to create 4 comparator blocks, one for each bit of the input. For each bit `i`, we assign the output `GT[i]` to be 1 if `A[i]` is 1 and `B[i]` is 0, and `EQ` is false (i.e., we haven't already determined that `A` and `B` are equal). We also update `EQ` to be true if `A[i]` and `B[i]` are equal and `EQ` is already true. Finally, we output the overall `EQ` value and combine all the `GT` values with an OR gate to get the final `GT` output.