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As sequential circuits follow a series of events or states to generate the desired output, there should

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be a mechanism to put the circuits into a known starting state.

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In other words, to reset the circuits when they want to start performing their associated tasks.

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Usually a recent signal in a sequential circuit has the responsibility of putting the circuit into a

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known state, this lecture talks about this recent mechanise in the following slides.

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I will define the that signal and how Attila's implements the.

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A typical day, flipflop usually has a recip or clear signal to put that into a known estate in which

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the output is usually zero, regardless of the logic value on the date.

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But there is that signal can be active, high or active low.

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In the active high case, the high logic value on the research signal clears a target flipflop.

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As long as the signal is high, the flipflop output is zero.

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Inactive low case, the low logic value on the reset signal clears the target flipflop.

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As long as the recent signal is low, the flip flop out with the zero.

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If there is a signal changes a state without considering the clock signal, then it is called asynchronous

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results.

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Alternatively, if it waits for the following edge off the clock to reset flipflops in the circuit,

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it is called synchronous reset.

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Let's consider the flip flop and its associated signals, if there is a signal is active, high and

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asynchronous, then the cue output would be zero.

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As soon as there is a signal goes high, when there is a signal is low, flipflop acts normally and

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samples the input and the rising edge of the clock.

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If there is that signal is active, high, but Synchronoss, then when it goes high, the volume rising

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age of the clock clears the flipflop when there is that signal is low flipflop acts normally and samples

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input data at the rising edge of the clock.

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There are three configuration parameters invited, such a class that controls the recent behavior.

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The first one determines which group of flipflops should have the results signal, there are four options,

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none control state and all.

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The nun and all options are almost clear why the former removes the recent signal from the design.

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The latter adds that to all memory cells.

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Understanding the impact of the two other options requires more knowledge about the design implementation

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in each of us.

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I will explain that later in this course.

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Another option is the asynchronous result there is that signal is synchronous by default, if you want

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to make that asynchronous, you should select this option.

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The last parameter determines that the result is active, high or active low, the default value is

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active high.

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Note that when the sentence the school considers your memorizers or flipflops in your synthesised code,

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it automatically as there is and clock signals to the generated article description.

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These signals are not accessible in the high level C C++ code.

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Our individual flipflops, the only memory cell elements in a sequential design.

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The next lecture will handle this question by introducing you to Register's.

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These are our takeaway messages, sequential circuits usually have a reset signal that puts that into

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a known state, there is that signal can be active, high or active low.

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There is a signal can be synchronous or asynchronous.

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Now, the quiz question, let's consider these two flipflops, assume that the dimple has been one for

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a long time.

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If there is that signal is active, high and synchronous, then find the Q1 and Q2 signals.