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Welcome the lab to Rio in this lab we created a shift register.

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And so in this video I'm going to show you the complete solution on the basis to form.

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Now that one wasn't that hard was it a lot to do this is a little bit more difficult.

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And that didn't give you a complete solution and so you're going to have to come up with some of this

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on your own.

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However if you're if you are stuck Don't worry it isn't a safe situation.

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When I first started learning VHDL I had many many struggles.

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I don't you mean the same but as I was so feel Feel free to email me and let you know any problems you

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have I'm more than happy to help.

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Here is the lab to the shift register running on the bases to board from the U.S. a file I gave you.

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You've got your outputs A B C and D which are indicated by the rightmost Ltd's on the front of your

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board and then your data in is this first time switch right here and then your clock is this button

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right here.

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And the reset button on the far right over here.

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Now where is the shift register works.

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Is my data in pen.

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Any time I actually get a clock signal which is indicated by I'm pushing this button right here a piece

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of data is going to be represented on the shift register.

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So for example here right now my data is zero.

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So if I hit my clock you won't see anything on the shift register which is indicated on the ladies.

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Now if I give myself a data in one and I hit that button you'll see I've got the one on the list the

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lights up to indicate a bit of one in that shifted his position.

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Now I knew this fact and was zero and hit the clock.

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It's going to shift this bit to the right which you see there it shifts over there.

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And if I hit the clock again it'll shift once more.

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Now if I turn my data in bet given a logical high turn that on a clock and see I've got another bet

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that shows up on the shift register right there.

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And so I can just do this I can go through all toggle down turn them on if I can do.

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And this is how like when you see a circuit that does like a twinkling thing you'll see we're basically

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just doing this and real fast succession where you got every other bet.

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Lights it up type of deal.

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And then also over here you got the reset button.

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Now I know from the VHDL code you couldn't load on here the reset all it resets on clock cycles so if

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I hit the reset right now nothing's going to happen.

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But what I have to do is have to reset down the clock button and it resets the entire shift register.

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So for example I go through here fill the whole shift register up.

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Now if I hit the reset nothing happens.

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That's because it needs to happen on a clock edge.

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So if I hold the reset down and hit a clock then there you go.

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Clears the shift register.

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And the reason it put the clock on this button is because this board is running inherently at 50 megahertz

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and if 50 megahertz if I run out here you ask yourself of that switch all those oldies turn on just

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like that.

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You you can't you wouldn't be able to tell what was going on.

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So that's the reason the clock right here so you can actually physically see and what's actually going

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on inside of the board.