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How can we check the validity of the data value and report this lecture will address this question by

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introducing the AP underscore will the portal ever interface?

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As we have learned, the AP underscored port interface implements the port, it simple wires, and it

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is the designer's responsibility to guarantee that the ports data values are valid at the time of sampling

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and usage.

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However, this condition cannot be satisfied in all designs, especially in the multi cycle circuits.

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For this reason, attaching ability to signal to a port can help the circuit to check if the port's

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data value is valid for sampling the API underscore will.

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The port interface helps us to attach such a signal to each port.

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This timing diagram shows the relation between the port data value signal and the corresponding valid

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signal.

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And the import the design will check the valid signal, if it's active, then the input data can be

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sampled and the output port, whatever the design assigns a proper value to an output port.

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It also activates the corresponding valid signal.

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So in summary, for input arguments, the design reads the data port as soon as the valid is active,

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even if the design is not ready to read new data.

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It samples the data port and holds the data internally until needed.

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For output arguments, why does such a. impediments and output signal to indicate when the data on the

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output port is valid?

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How can a design inform other modules that the census data is used in a communication process with other

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modules, the next lecture will cope with this question.

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These are our takeaway messages in a multi cycle design, the data should be valid when a consumer module

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samples that therefore there should be a mechanism to report the data validity on a court.

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The AP underscore will report interface invited socialist's adds a validity signal to a dateable.

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Now, the quiz question.

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Consider the following other design, synthesize the code and perform the RTL simulation and check the

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AP underscore will the signaling in the waveform window.