Sytemverilog provides set of pre defined methods to work on covergroup. Below list of methods.

• void sample() : Triggers the sampling of covergroup
• real get_coverage() : Calculate coverage number, return value will be 0 to 100
• real get_inst_coverage() :Calculate coverage number for given instance, return value will be 0 to 100
• void set_inst_name(string) :Set name of the instance with given string
• void start() :Start collecting coverage
• void stop() :Stop collecting coverage

  1 module test();
  2 
  3 logic [2:0] addr;
  4 wire [2:0] addr2;
  5 
  6 assign addr2 = addr + 1;
  7 
  8 covergroup address_cov;
  9   ADDRESS : coverpoint addr {
 10     option.auto_bin_max = 10;
 11   }
 12   ADDRESS2 : coverpoint addr2 {
 13     option.auto_bin_max = 10;
 14   }
 15 endgroup
 16 
 17 address_cov my_cov = new;
 18 
 19 initial begin
 20   my_cov.ADDRESS.option.at_least = 1;
 21   my_cov.ADDRESS2.option.at_least = 2;
 22   // start the coverage collection
 23   my_cov.start();
 24   // Set the coverage group name
 25   my_cov.set_inst_name("ASIC-WORLD");
 26   $monitor("addr 8'h%x addr2 8'h%x",addr,addr2);
 27   repeat (10) begin
 28     addr = $urandom_range(0,7);
 29     // Sample the covergroup
 30     my_cov.sample();
 31      #10 ;
 32   end
 33   // Stop the coverage collection
 34   my_cov.stop();
 35   // Display the coverage
 36   $display("Instance coverage is %e",my_cov.get_coverage());
 37 end
 38 
 39 endmodule

 addr 8'h6 addr2 8'h7
 addr 8'h4 addr2 8'h5
 addr 8'h5 addr2 8'h6
 addr 8'h2 addr2 8'h3
 addr 8'h3 addr2 8'h4
 addr 8'h7 addr2 8'h0
 addr 8'h0 addr2 8'h1
 addr 8'h7 addr2 8'h0
 addr 8'h6 addr2 8'h7
 addr 8'h3 addr2 8'h4
 Instance coverage is 8.750000e+01

 ===========================================================
 Group : test::address_cov
 ===========================================================
 SCORE  WEIGHT GOAL   
  87.50 1      100    
 -----------------------------------------------------------
 Summary for Group   test::address_cov
 
 CATEGORY  EXPECTED UNCOVERED COVERED PERCENT 
 Variables 16       2         14      87.50   
 
 Variables for Group  test::address_cov
 
 VARIABLE EXPECTED UNCOVERED COVERED PERCENT GOAL WEIGHT 
 ADDRESS  8        1         7       87.50   100  1      
 ADDRESS2 8        1         7       87.50   100  1      
 -----------------------------------------------------------
 Summary for Variable ADDRESS
 
 CATEGORY                     EXPECTED UNCOVERED COVERED PERCENT 
 Automatically Generated Bins 8        1         7       87.50   
 
 Automatically Generated Bins for ADDRESS
 
 Uncovered bins
 
 NAME      COUNT AT LEAST NUMBER 
 [auto[1]] 0     1        1      
 
 Covered bins
 
 NAME    COUNT AT LEAST  
 auto[0] 1     1        
 auto[2] 1     1        
 auto[3] 2     1        
 auto[4] 1     1        
 auto[5] 1     1        
 auto[6] 2     1        
 auto[7] 2     1        
 -----------------------------------------------------------
 Summary for Variable ADDRESS2
 
 CATEGORY                     EXPECTED UNCOVERED COVERED PERCENT 
 Automatically Generated Bins 8        1         7       87.50   
 
 Automatically Generated Bins for ADDRESS2
 
 Uncovered bins
 
 NAME      COUNT AT LEAST NUMBER 
 [auto[2]] 0     1        1      
 
 Covered bins
 
 NAME    COUNT AT LEAST  
 auto[0] 2     1        
 auto[1] 1     1        
 auto[3] 1     1        
 auto[4] 2     1        
 auto[5] 1     1        
 auto[6] 1     1        
 auto[7] 2     1        

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Deepak Kumar Tala - All rights reserved

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