Using parameters to create constant in verilog

verilog
Floose picture Floose · Jan 21, 2014 · Viewed 37.2k times · Source

I want to take in a parameter and assign a number of zeroes equal to the paramter to a constant, and use this constant for comparison. how do I do it ?

For example, say parameter is 3, I want to create a constant 

n=3'b000;

and use this n in another statement. Only thing is, I don't know n. How do i initialize 'n' zeroes and to what verilog data type do I assign it to ?

Answer

Greg picture Greg · Jan 21, 2014

Your looking for the replication operator. The syntax is {replication_constant{value}}.

An example of creating a bus of size WIDTH to all zeros.

parameter WIDTH = 3;
wire [WIDTH-1:0] n = {WIDTH{1'b0}};

For full description of the replication operator, see IEEE std 1800-2012 § 11.4.12.1 "Replication operator"

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