WEBVTT 00:01.360 --> 00:06.090 Welcome the lab to Rio in this lab we created a shift register. 00:06.190 --> 00:10.860 And so in this video I'm going to show you the complete solution on the basis to form. 00:10.960 --> 00:16.090 Now that one wasn't that hard was it a lot to do this is a little bit more difficult. 00:16.190 --> 00:20.320 And that didn't give you a complete solution and so you're going to have to come up with some of this 00:20.320 --> 00:20.970 on your own. 00:21.100 --> 00:25.330 However if you're if you are stuck Don't worry it isn't a safe situation. 00:25.330 --> 00:29.630 When I first started learning VHDL I had many many struggles. 00:29.770 --> 00:35.950 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 00:35.950 --> 00:38.110 have I'm more than happy to help. 00:38.240 --> 00:44.860 Here is the lab to the shift register running on the bases to board from the U.S. a file I gave you. 00:44.890 --> 00:53.320 You've got your outputs A B C and D which are indicated by the rightmost Ltd's on the front of your 00:53.320 --> 01:01.030 board and then your data in is this first time switch right here and then your clock is this button 01:01.120 --> 01:02.080 right here. 01:02.440 --> 01:06.440 And the reset button on the far right over here. 01:06.520 --> 01:08.490 Now where is the shift register works. 01:08.570 --> 01:11.050 Is my data in pen. 01:11.170 --> 01:16.200 Any time I actually get a clock signal which is indicated by I'm pushing this button right here a piece 01:16.210 --> 01:18.670 of data is going to be represented on the shift register. 01:18.670 --> 01:21.820 So for example here right now my data is zero. 01:22.000 --> 01:27.280 So if I hit my clock you won't see anything on the shift register which is indicated on the ladies. 01:27.280 --> 01:33.730 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 01:33.730 --> 01:38.520 lights up to indicate a bit of one in that shifted his position. 01:38.530 --> 01:41.010 Now I knew this fact and was zero and hit the clock. 01:41.050 --> 01:46.490 It's going to shift this bit to the right which you see there it shifts over there. 01:46.700 --> 01:50.140 And if I hit the clock again it'll shift once more. 01:50.140 --> 01:56.970 Now if I turn my data in bet given a logical high turn that on a clock and see I've got another bet 01:56.980 --> 02:00.620 that shows up on the shift register right there. 02:00.730 --> 02:06.370 And so I can just do this I can go through all toggle down turn them on if I can do. 02:06.640 --> 02:11.130 And this is how like when you see a circuit that does like a twinkling thing you'll see we're basically 02:11.140 --> 02:16.120 just doing this and real fast succession where you got every other bet. 02:16.140 --> 02:19.070 Lights it up type of deal. 02:19.120 --> 02:22.020 And then also over here you got the reset button. 02:22.030 --> 02:29.620 Now I know from the VHDL code you couldn't load on here the reset all it resets on clock cycles so if 02:29.620 --> 02:32.190 I hit the reset right now nothing's going to happen. 02:32.530 --> 02:38.850 But what I have to do is have to reset down the clock button and it resets the entire shift register. 02:39.130 --> 02:43.170 So for example I go through here fill the whole shift register up. 02:43.180 --> 02:45.340 Now if I hit the reset nothing happens. 02:45.550 --> 02:48.260 That's because it needs to happen on a clock edge. 02:48.280 --> 02:52.230 So if I hold the reset down and hit a clock then there you go. 02:52.230 --> 02:53.770 Clears the shift register. 02:53.770 --> 03:01.150 And the reason it put the clock on this button is because this board is running inherently at 50 megahertz 03:01.570 --> 03:06.650 and if 50 megahertz if I run out here you ask yourself of that switch all those oldies turn on just 03:06.700 --> 03:07.250 like that. 03:07.270 --> 03:10.460 You you can't you wouldn't be able to tell what was going on. 03:10.480 --> 03:16.120 So that's the reason the clock right here so you can actually physically see and what's actually going 03:16.120 --> 03:17.060 on inside of the board.