1 00:00:03,680 --> 00:00:04,310 All right. 2 00:00:04,310 --> 00:00:05,660 Welcome back. 3 00:00:05,720 --> 00:00:14,040 So let's continue the fact must compile and rebuild our program to see how it looks so far. 4 00:00:14,300 --> 00:00:17,290 Click here to rebuild our margins. 5 00:00:17,390 --> 00:00:21,220 And we've got zero errors two warnings. 6 00:00:21,320 --> 00:00:25,050 So let's start by creating the prototype of our functions. 7 00:00:25,100 --> 00:00:30,940 Just copying each function and put it up here and it's it's called on at the end. 8 00:00:31,560 --> 00:00:33,230 Then copy this as well 9 00:00:38,910 --> 00:00:48,700 plays this up here dance and call them then which add a function we have to put in it to function. 10 00:00:48,880 --> 00:00:52,940 This place it up here in the corner. 11 00:00:54,040 --> 00:01:00,490 Then the final function which is to measure distance. 12 00:01:00,840 --> 00:01:13,540 Copy this and then put here as well to form function. 13 00:01:13,920 --> 00:01:16,070 Let's just fix this over here. 14 00:01:16,890 --> 00:01:17,440 OK. 15 00:01:17,550 --> 00:01:19,720 Floyd says nice. 16 00:01:19,980 --> 00:01:22,200 So let's test our code. 17 00:01:22,200 --> 00:01:29,010 We stopped by calling the port in its function to initialize our GPL you pot. 18 00:01:29,280 --> 00:01:36,630 And then we initialize time of zero from the time as you need to function like this. 19 00:01:38,130 --> 00:01:42,190 Then we create a while 1 Loop infinite loop. 20 00:01:42,540 --> 00:01:49,710 And what I'm going to do is just going to create a new local variable or I'll make it a global variable 21 00:01:49,740 --> 00:01:51,090 to code the return. 22 00:01:51,110 --> 00:02:02,550 But the use of the measure de function I'm going to call this new variable you 8 in 32 distance in centimeters 23 00:02:03,360 --> 00:02:13,590 and we're going to start a return for you both with the measured dysfunction in this in this variable 24 00:02:13,590 --> 00:02:14,170 like this. 25 00:02:14,220 --> 00:02:17,690 So this variable would have the distance centimeters. 26 00:02:17,940 --> 00:02:27,810 And once this is measured we can in fact use the M the decision or the funding here to perform other 27 00:02:27,810 --> 00:02:28,450 functions. 28 00:02:28,450 --> 00:02:29,630 Well I'm going to do it. 29 00:02:29,640 --> 00:02:31,920 I'm going to see. 30 00:02:32,070 --> 00:02:38,640 I'm going to check if the distance between the object and the orcas will make sense or is it less than 31 00:02:38,640 --> 00:02:43,180 the 16 centimeters then 10 on the plurality. 32 00:02:43,200 --> 00:02:51,450 That is why we initialize the entity just to create this so we can just see if mission D is less than 33 00:02:52,920 --> 00:02:54,850 15 10 on the LCD. 34 00:02:54,990 --> 00:03:01,530 I know I'm using Measure D here and it looks as if our distance in centimeters spread well it's useless. 35 00:03:01,530 --> 00:03:07,230 I put this here because when we go to the debug view I want to up this variable to the watch window 36 00:03:07,320 --> 00:03:14,880 and see as it finally changes when I move my hand up and down on top of the okra or in front of the 37 00:03:14,940 --> 00:03:25,530 ultrasonic sense or so let's compile and see it all good and I'm going to download onto my board 38 00:03:28,740 --> 00:03:29,070 still. 39 00:03:29,080 --> 00:03:29,570 Good 40 00:03:32,920 --> 00:03:34,900 so the next step is. 41 00:03:34,960 --> 00:03:38,650 Hook up your ultrasonic sensor according to this schematic. 42 00:03:38,650 --> 00:03:45,490 You can connect the FEC to the ultrasonic to another microcontroller that has a five root source or 43 00:03:45,490 --> 00:03:53,530 in fact if you have a five volt battery five volt adapter or a five foot power supply you can connect 44 00:03:53,980 --> 00:03:59,550 the PCC to the five or 10 in the ground to the ground of that particular five source. 45 00:03:59,560 --> 00:04:06,650 This is because the TWC Launchpad provides just three point three vote and the ultrasonic sensor requires 46 00:04:06,910 --> 00:04:08,770 five fold to operate. 47 00:04:09,090 --> 00:04:13,350 I tested on the three point three Volt and it wasn't working well. 48 00:04:13,360 --> 00:04:19,870 So to get its 5 volt and connect it to when that is done and it's connected and you've downloaded everything 49 00:04:19,930 --> 00:04:22,200 you need to come to the debug view like this. 50 00:04:22,200 --> 00:04:28,430 And what we need to do is add this variable here to the watch window right away. 51 00:04:28,540 --> 00:04:29,860 Double click like this. 52 00:04:29,890 --> 00:04:36,520 And then right click and select a distance and see what we know why we have it over here now. 53 00:04:36,710 --> 00:04:40,880 It could click on right click and then on. 54 00:04:40,890 --> 00:04:47,630 Check this to display the number in decimal mode so to run the code you simply press this and it could 55 00:04:47,630 --> 00:04:48,430 just run it. 56 00:04:48,520 --> 00:04:55,060 Karen Lee this the distance in centimeters cause the ultrasonic sensor is just pointing upwards. 57 00:04:55,150 --> 00:04:59,200 So basically does the distance between the sensor or in my ceiling. 58 00:04:59,200 --> 00:05:01,630 I'm sitting in a room not very high. 59 00:05:01,630 --> 00:05:06,260 It's two point three meters the ceiling from the table. 60 00:05:06,260 --> 00:05:07,900 So that's the voltage sometimes. 61 00:05:08,260 --> 00:05:09,250 My hand is above it. 62 00:05:09,250 --> 00:05:12,440 No I'm moving closer. 63 00:05:12,850 --> 00:05:16,050 Way way. 64 00:05:16,530 --> 00:05:20,060 And as you can see the blue lights on and it's staying on. 65 00:05:20,290 --> 00:05:22,850 This is because we've just set it to stay on. 66 00:05:22,850 --> 00:05:31,450 We've not added else condition saying if the distance is greater than or less than 15 go off this condition 67 00:05:31,450 --> 00:05:32,940 just turns it on. 68 00:05:32,940 --> 00:05:35,860 There's no other condition that tennis it off. 69 00:05:35,860 --> 00:05:43,030 So we can just change that now and then make sure the light is fully turned on when the measured distance 70 00:05:43,150 --> 00:05:45,970 is below 15 centimeters. 71 00:05:46,030 --> 00:05:49,660 So I'm going to do that now and then run it again and we see 72 00:05:52,840 --> 00:06:01,270 I'm going to say ls shortest way to solve this is to use on as an Ellis statement just see ls 73 00:06:04,630 --> 00:06:09,390 just to say this sentiment in activities like this. 74 00:06:09,460 --> 00:06:11,790 This the same much writing 0 0 0. 75 00:06:11,980 --> 00:06:19,990 But if I race here x years you're going to disable audit pins in GPI f whereas if I do this I'm disabled 76 00:06:19,990 --> 00:06:23,270 in just that pin of the blue LCD. 77 00:06:23,620 --> 00:06:32,850 So I'm going to rebuild and I'm going to download onto my board and as you can see when I take off my 78 00:06:32,850 --> 00:06:35,610 hand the goes on as well. 79 00:06:35,610 --> 00:06:36,900 And this is it guys. 80 00:06:36,900 --> 00:06:41,490 This is how you can use fuse timers to right other drivers. 81 00:06:42,000 --> 00:06:48,840 So in the next and final section we're going to learn about timer interrupt going to learn about how 82 00:06:48,840 --> 00:06:51,600 to use time is to invoke interrupt. 83 00:06:52,140 --> 00:06:58,650 And with that we would complete the the cortex in time is cookbook. 84 00:06:58,650 --> 00:07:03,470 We've covered all the major in fact everything you need to know about timers. 85 00:07:03,540 --> 00:07:05,600 So I'll see you in the next lesson.