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‫Welcome to the boose rhythm demonstration on the basis to develop a board for this demonstration we're

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‫using the boarded at 770 display located on the basis seaboard.

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‫We also are using a push button zero to simulate a clock with a barrel shifter or switch 0 and switch

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‫one are used selected to determine what we're doing with our barrel shifter if we're shifting right

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‫shifting left loading holding.

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‫So on and so forth.

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‫And our switch seven six and five are used to determine what shift amount.

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‫We'll be going for.

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‫We're shifting left to right.

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‫How much will be shifting.

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‫So to start out if we we have an initial value that we're loading into a register which is 128.

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‫So the first thing we can do if we set our switch one switch 0 2 0 1.

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‫We're going to shift to the right and by setting our shift amount by a switch 7 6 and 5 to 2 or 2 1

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‫what we're going to do is shift our bits right to one which is the same as a divide by two.

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‫So if I press that button we now divided from 128 to 64 and that's the key thing with the barrel shifter

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‫is you can go from a number such as 128 divided by 2 6 4 and we did that in one clock cycle.

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‫And so now if I pull my switch down we have a one and we go to a two hour shift right.

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‫Two-Bits.

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‫We're now dividing by four.

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‫So 64 two by four gives us 16 and we can keep going down.

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‫So now I can divide by 2 again.

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‫Sixty two gives me eight.

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‫And so we're able to do these operations really fast just one clock cycle so they're extremely cheap.

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‫Now if we go and let's get our.

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‫So now we're going to shift left operation which if we shift left.

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‫It's the same as multiplying.

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‫So we have right now set to 2 or 1 to be multiply by 2.

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‫If we said it we're going to shift left to bits which is multiplying by four or button gives us 32.

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‫Now if we go and make it two we shift left one bit.

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‫So now it's going to be multiplied by 2 and 32 times to 64.

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‫Now going to 64.

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‫So we can shift left and do a multiply multiply by multiples of 2 or shift right and divide by powers

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‫of 2.

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‫And also we can do better.

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‫So we have a load operation.

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‫So if we put both switches up high.

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‫Which ones which Zero will load it.

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‫And that's what the preconfigured value.

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‫Now if you were designing some sort of embedded processor or another piece of computer hardware you

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‫would have it.

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‫So the user or the code however you have it can load whatever pre-configured valued wanted your barrel

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‫shifter.

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‫So for example if you're making Alieu and you want that you've got to do it divide by two real quick.

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‫You had your load.

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‫That's one clock cycle.

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‫Now your second clock cycle you're going to change your configuration to switch one to high and your

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‫switch three.

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‫Once you're on shift right one bit.

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‫So the next clock cycle you're already divided by two 64 or most other multiplication or division algorithms

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‫will take multiple clock cycles.

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‫These can happen in one clock cycle and that's the whole thing we're trying to show with the barrel

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‫shifter is that in one clock cycle you can do a multiply or divide as long as it's the power of two.

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‫And that is that the barrel shift or demonstration running on the base is to board.