Need signal edge detection idea

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EDA_hg81

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Do any one has idea about how to detect the signal edge?

Thanks.
 

IF you mean digital signal thats easy if you use microcontroller. Most external interrupts of MCUs can be configured to detect either on Rising or falling edge of a signal or you can poll a signal line in a loop. And can be even be switch back and forth as the program is running. Although the drawback here is you need to code plus teh latency in edge detection may be in the magnitude of microsecs which may not be acceptable in your application
 

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    EDA_hg81

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If you sample the signal in question with a flip flop, whenever the input to the flip flop is at a different level than the output, you have detected an edge.
 

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    EDA_hg81

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Hi, I dont know what do you need it for and what kind of output you would like to see when there is an edge in the input. But if you do this:

pass the input I1 through a dff to get a signal I1_delayed, then xor I1 and I1_delayed to get edge_pulse, then edge_pulse will be a one clock pulse, produced whenever I1 makes a transition from 0->1 or 1->0.
Kr,
Avi
http://www.vlsiip.com
 

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    EDA_hg81

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litle comment:


If you are going to do one of the abome mentioned methods, make sure signal rising/filing time, still resanoble fast enought to avoid glitches otherwise you will have problems,

Try for example to detect risingfiling edge on signal from parallel port of the PC and use 100MHZ clock
 

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    EDA_hg81

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I am trying this method and let you know the result.

Thanks.
 

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