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‫Welcome to the linear feedback shift register demonstration with the RTC 7 board we are implementing

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‫a 16 bit linear feedback shift register that is implementing the Fibonacci sequence.

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‫And what this means is we have up to 65000 535 different combinations of numbers before we have a repeat.

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‫So every time we press our button zero or clock our linear feedback shift register will generate a pseudo

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‫random number and the setup we have is a four digit seven segment display that each of the segments

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‫are connected to the J.

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‫Pieman port of the Arty's the seven through a 56 ohm resistor.

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‫We also have four digit selects on the 7:7 display that are connected using a 2 and 13 3:51 transistor

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‫connected through the 470 ohm resistor and these are all fed into the J B P port of the RTC 7 and the

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‫switch 0 we have as our Reset which is active high.

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‫Meaning if we have it high will reset our linear feedback sophister And if we have it low will not be

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‫in a reset state.

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‫And our clock is this button zero on RTC 7.

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‫So if I press my button 0 it'll bring up the next value in the linear feedback shift register which

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‫is a 4 0 0 0 and these values are displayed in hex.

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‫So if I keep pressing the button zero button you'll see it keeps generating numbers that appear to be

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‫random.

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‫There's no specific sequence to these numbers so I can just keep pressing and generating all kinds of

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‫different numbers if I press this sixty five thousand six hundred sixty five thousand five hundred thirty

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‫five times eventually I'll come back to 0 0 1.

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‫Now if I want to reset at any point in time I can slide my switch up which puts me back to my 0 0 1

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‫value which is the seed value for this linear few x shift register.

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‫Anyway these combinations we can use a seed value because whatever your seed value is will dictate what

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‫your next value is.

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‫So on and so forth.

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‫However beings that we have in 0 0 1 just because it's easy for us to know.

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‫But if you want to truly generate random numbers you would want to make sure that you don't know what

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‫the seed value is and it's constantly changing so that the numbers appear to be random.

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‫And so you can just keep pressing the button through and you'll see if we follow the same pattern.

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‫Just we did before but we just keep pressing and go on for further.

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‫Notice that there's just all kinds of different numbers I mean like you said there's a 16 bit value.

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‫And with the feedback functions we have selected will have sixty five thousand five hundred thirty five

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‫different combinations and that is the linear feedback shift register demonstration running on the ardy

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‫the seven board.