Debounce Verilog ( I have some questions)

The filter time must be longer than the bouncing settling time.

An unfiltered pushbutton is likely to have bouncing spikes extending in the 100us - 1ms range, so you need to sample the level for a few ms.

With a 24MHz and 8 samples you achieve a filter "low pass" frequency of about 3MHz which is totally ineffective.

You must use a lower frequency sampling: if you keep the 8 samples, choose a sample rate around 10kHz.

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The filter time must be longer than the bouncing settling time.

An unfiltered pushbutton is likely to have bouncing spikes extending in the 100us - 1ms range, so you need to sample the level for a few ms.

With a 24MHz and 8 samples you achieve a filter "low pass" frequency of about 3MHz which is totally ineffective.

You must use a lower frequency sampling: if you keep the 8 samples, choose a sample rate around 10kHz.

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thanks. but, what do you mean? i change my 24MHz clock? or the number of samples? i tried increasing the number of samples, still i get same results. please help.

You can keep on using the 24mhz clock and 8 sample. You can simply define a counter and inside the always @(posedge clk) process you place the sampling in a conditional statement. For example:

counter <= counter + 1;

if (counter == 1000)

begin

<sample here the input>

counter <= 0;

end

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You can keep on using the 24mhz clock and 8 sample. You can simply define a counter and inside the always @(posedge clk) process you place the sampling in a conditional statement. For example:

counter <= counter + 1;

if (counter == 1000)

begin

<sample here the input>

counter <= 0;

end

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dude please help. i changed my debouncer to this one:

module dbc(pbnoisy, clk, pbclean);

input wire pbnoisy, clk;

output reg pbclean;

parameter N=8;

reg [ N - 1 : 0 ] ctr;

reg [ 12 : 0] M;

initial

begin

M <= 0;

pbclean <= 0;

end

always @(posedge clk)

begin

M = M + 1;

if (M == 3_000_000) pbclean <= 1;

else pbclean <= 0;

end

endmodule

and on my main code i called it by this:

wire pb3;

dbc dbc3( !PB[3], ClOCK_24A, pb3);

also i used this for incrementing:

if (pb3)

begin

ctr <= ctr + 1;

end

however, nothing happens when i press PB[3]. what should be done?

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however, nothing happens when i press PB[3]. what should be done?

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That's correct!

According to your code nothing should happen.

You'd better consider how the input signal 'pbnoisy' is supposed to affect the output... since you don't use it.

Moreover, I'd reset M when you reach the threshold condition, otherwise you'd have one-shot operation.