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How to detect an edge on a given signal.

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This lecture will propose a straightforward coding style to detect rising and falling edges on an input

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signal.

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There are several times in logic controller designs that we should detect and age on an input signal.

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Here I will describe a simple sequential circuit to detect a rising or falling edge on a given signal.

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The second receives an input signal and generates two outputs rising and falling at.

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A single cycle pulse is assigned to each output if rising or falling edge is detected on the input signal.

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Let's write the code to logic levels should be distinguished to detect and act one before the edge and

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the other after, these two levels should not be the same.

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To keep the logical level before the edge, we need a static variable.

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Let's call it previous input signal.

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Now, using an if else statement, we can detect the edges on the signal.

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Whereas the first condition detects the rising edge, the second one detects the following edge.

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After detecting the edge, we should update the previous input signal, preparing for detecting the

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next stage.

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Now, let's see the code behavior invited suchness.

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Create a new project and add the edge detector is code attached to this lecture, if you would like

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to change the font size right, click somewhere inside or then select preferences, then click on the

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text Ed link and then click on the colors and fonts link.

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Finally, click on the edit button and change the font size.

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Check the design, Sourcefire.

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As explained earlier, it contains a static variable and a set of false statements.

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Now, let's check the test benchmark.

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The follow up applying 13 keeps the input signal at low level for ten clock cycles.

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The second look at line 19 changes the input signals voltage level to high and maintains that 14 clock

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cycles.

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The third group outlined 26 changes, the input signals voltage level to low and maintains that for

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10 cycles.

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Now we can perform the simulation and check it out.

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As we can see, the design description can detect the rising and falling edges on the input signal.

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After performing a high level sentences, let's check the analysis perspective and ensure that the design

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description is synthesized into a single cycle article code.

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To check the cycle, accurate signals in a way form viewer performed the artillery simulation and don't

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forget to select All in the dump race, which.

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Click on the open waveform viewer, the viewer will appear.

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The design signals, as well as the clock signal and check the output signals.

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This video is the last lecture explaining how to design a fuel utility logic circuits.

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Therefore, the next lecture will give you some exercises to review and master the techniques and coding

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styles you have learned throughout this section.

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To detect an edge on a given signal, you can save the signal level in a register and then compare the

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current signal level with the previous one.

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If they do not match, then there is an edge on the signal.

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Now, the quiz question, describe a logic circuit that detects two simultaneous rising edge on two

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different input signals.