VHDL simulating a clock that doesn't run all the time

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shaiko

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Hello,

Signal x is a simulated clock that's defined as follows:
Code: 
signal x : std_logic := '0' ;
x <= not x after 10ns ;

Suppose, I want x to start running after 100ns and stop after 1000ns.
The obvious solution will be to mux it...my question:

Is there a simple simulation syntax that allows to do that without using a mux?
 

You can use this.
x <= '0', not x after 100 ns, '0' after 1000 ns;
 
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    shaiko

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sharath666 said:
You can use this.
x <= '0', not x after 100 ns, '0' after 1000 ns;
Click to expand...

That wont make a clock, that will just set it high for 900 ns.

The easiest option is a mud like you suggested, or a process with control loops.
 
Code VHDL - [expand]
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Process
Begin
  input <= '0';
  wait for 100ns;
 
  for I in 1 to 90 loop 
    input <= not input;
    wait for 10 ns;
  end loop;
 
 input <= '0';
End process;
 
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    shaiko

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A terminating wait statement should stop further process schedule.
 

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