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Can we initialize wire in Verilog?
A Verilog wire doesn’t have storage, so an initial value wouldn’t make much sense. If you don’t continuously drive a wire, it’s value will be ‘z’. In Verilog 2001 you can specify a reg initial value, as rsrinivas described. However some synthesis tools don’t support it.
Why do we use wire in Verilog?
wire elements are used to connect input and output ports of a module instantiation together with some other element in your design. 2. wire elements are used as inputs and outputs within an actual module declaration.
What is difference between wire and reg?
wire elements must be continuously driven by something, and cannot store a value. Henceforth, they are assigned values using continuous assignment statements. reg can be used to create registers in procedural blocks. Thus, it can store some value.
Why wire is used in Verilog?
What’s the difference between a wire and a Reg in Verilog?
\\$\\begingroup\\$. The only real difference between wire and reg declarations in Verilog is that a reg can be assigned to in a procedural block (a block beginning with always or initial), and a wire can be assigned in a continuous assignment (an assign statement) or as an output of an instantiated submodule.
What’s the best way to assign output in Verilog?
If you plan to assign your output in sequential code,such as within an always block, declare it as a reg (which really is a misnomer for “variable” in Verilog). Otherwise, it should be a wire, which is also the default.
What’s the difference between a Reg and an output wire?
The only difference between the two code examples you provided is that the output wire c adds an additional connection between reg b and the output from the module. Regs are meant to represent data storage elements, meaning it can store a value from one assignment to the next.
Which is the output of a Reg net?
Because of this difference, wire nets are almost always the output of combinatorial logic or submodules. But reg nets might be the output of either sequential or combintatorial logic, for example when a case statement in an always block is used to infer a multiplexer.