Microsoft Word - Digital Logic Design v_4_6a

case(step)

0 : $display ( "starting step” );

1 : $display ( "step number 2" );

2 : $display ( "step 3" );

default : $display ( "undefined step" );

endcase

 While Loop
statements in “while” loop executes a code segment as long as the while condition is true. While loop
syntax is shown below:

 Example -

count = 0;

while (count < 12)

count = count +3;

end

 For Loop

 Example -

// This code displays counts from 0 to 30.

for (count= 0; count < 31; count = count +1) begin

$display ( "Count is %d" , count);

end

for (initial; condition; end expression) // first initial will be done, if the condtion is true then

// for loop body is executed and at the end of loop

// execute the end expression.

begin

// for loop body

Statements

end

While (condition) // while condition is true the statements is executed and

// when condition is false, the loop will be terminating.

begin

Statements

end