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Altera_Forum's avatar
Altera_Forum
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18 years ago

DE2 Quartus debounced circuit

Hello, I am working on a senior design project and have a DE2 board connected to external circuitry. There are pushbuttons on the external circuit which control leds also on that circuit board. M...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
17 years ago

Hi,

Everytime I see code with parameters, some manual action has to be done for setting the bit-width of a register (counter).

There is a nice trick with a 'constant-function' to prevednt this action :

change this : 

   parameter N = CLogB2(dur);

and add : 

//ceil of the log base 2
function integer CLogB2;
	input  Depth;
	integer i;
	begin
	 	i = Depth;		
		for(CLogB2 = 0; i > 0; CLogB2 = CLogB2 + 1)
			i = i >> 1;
	end
endfunction