ALU design in VERILOG

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You don't instantiate the modules in the case statement, can't be done the language doesn't allow this. So get that out of your head. You're obviously thinking like a software programmer, where you can call some function in a case statement.

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Code Verilog - [expand]
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// instantiated add module
ADD ADD_inst (
  .A         (a_data),
  .B         (b_data),
  .A_PLUS_B  (output_bus_of_your_add_module)
);
 
// case statement is wrapped in some always block, (not shown)
case (alu_sel)
  `ALU_ADD : alu_result <= output_bus_of_your_add_module;
  `ALU_SUB : alu_result <= output_bus_of_your_sub_module;
  `ALU_SHL : alu_result <= output_bus_of_your_shift_left_module;
  //etc....
endcase

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[Salil Vaidya]

i got it.bt can you please post some example plz.....

 

[ads-ee]

My previous post HAS an example of using a multiplexer to select the ALU fucntion. If you want to learn something it requires effort on your part.

I give up.

okay one last try...

Read a Verilog tutorial...
https://www.asic-world.com/verilog/veritut.html

and learn something...wasn't that your plan for going to school in the first place?

 

[ruchibora]

Hi salil

There are three types of modelling in verilog- gate level, dataflow and behavioral.
I think you should use dataflow modelling, if you want to use module instantiation and then connect all instance acc to ur diagram.

 

[shahulakthar]

check this one

Verilog ALU