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module parity;

reg[31:0] addr;

regparity;

always @(addr)

begin

parity = calc_parity(addr);

end

unction calc_parity;

input [31:0] address;

begin

calc_parity = !address;

end

endunction

endmodule

module function_calling(a, b,c); 

input a, b ; 

output c; 

wire c; 

function myfunction; 

input a, b; 

begin 

myfunction = (a+b); 

end 

endfunction 

assign c = myfunction (a,b); 

endmodule 

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module tra"c_lig#ts;

reg cloc$% red% amber% green;

parameter on = 1% o& = 0% red_tics = 3'0%

amber_tics = 30% green_tics = 00;

initial red = o&;

initial amber = o&;

initial green = o&;

always begin se*uence to control t#e lig#ts+

red = on; turn red lig#t on

lig#t(red% red_tics); and wait+

green = on; turn green lig#t on

lig#t(green% green_tics); and wait+

amber = on; turn amber lig#t on

lig#t(amber% amber_tics); and wait+

end

tas$ to wait or tics positi,e edge cloc$s

beore turning color lig#t o&+

tas$ lig#t;

output color;

input [31:0] tics;

begin

repeat (tics) @ (posedge cloc$);

color = o&; turn lig#t o&+

end

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endtas$

always begin wa,eorm or t#e cloc$+

-100 cloc$ = 0;

-100 cloc$ = 1;

end

endmodule tra"c_lig#ts+

module auto_tas$();

tas$ automatic disp;

input integer a;

input integer d;

begin

-(d) .display(/t d is d a is d/% .time%d%a);

end

endtas$

initial

-10 disp(10%1);

initial

-1 disp(3%12);

initial

- disp(11%1);

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initial

-100 .nis#;

4ndmodule

Blocking Task 

module tb(); 

initial begin 

blocking_task(); 

# 5 $display(" Statement afte blocking_task at !t ",$time); 

end 

task blocking_task(); 

begin 

# ; 

$display(" statement inside blocking task at !t",$time); 

end endtask 

endmodule 

%S&'S

statement inside blocking task at 10

Statement after blocking_task at 15

module re_entrant_task();  2

3 task automatic print_value;  4 input [7:0] value;

  5 input [7:0] delay;

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  begin  7 !(delay) $display("%g Passed Value %d Delay %d"" $time" value" delay);

  # end  $ endtask %0%% initial begin

 %2 fork %3 #1  print_value (%0"7);

 %4 #1  print_value (#"5); %5 #1  print_value (4"2);

 %  join %7 #1 $finish;

 %# end %$20 endmodule

module 5ero_count_tas$ (data% out);

input [6:0] data;

output reg [3:0] out;

always @(data)

count_0s_in_byte(data% out);

tas$ declaration rom #ere

tas$ count_0s_in_byte(input [6:0] data% output reg [3:0] count);

integer i;

begin tas$ body

count = 0;

or (i = 0; i 7= 6; i = i 8 1)

i (data[i] == 0) count= count 8 1;

end endtas$

endmodule