How can a square wave that is random be produced for a specific duration?

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One way to produce a square wave that is random for a specific duration is to use a digital random number generator to produce a sequence of binary values that alternate between 0 and 1, and then use this sequence to control a digital output pin on a microcontroller or programmable logic device. The duration of the random square wave can be controlled by the length of the sequence of binary values produced by the random number generator, or by setting a specific time interval for the output waveform using a timer or counter. Alternatively, an analog noise source can be used to generate a random voltage waveform, which can then be converted to a digital signal using an analog-to-digital converter and processed to produce a square wave of the desired duration.