1 00:00:00,600 --> 00:00:01,750 Hello, welcome back. 2 00:00:01,790 --> 00:00:09,690 In this lesson, we going to see how to change the priority of a task during runtime using the Simms's 3 00:00:09,690 --> 00:00:16,230 artists to appraise, I've going ahead to make a copy of our last project, and I've given it the name 4 00:00:16,230 --> 00:00:18,150 thread priority over here. 5 00:00:18,300 --> 00:00:25,620 And we're going to run this simple experiment so we know how our current project works to refresh your 6 00:00:25,620 --> 00:00:26,020 memory. 7 00:00:26,040 --> 00:00:27,930 I'm simply going to run this. 8 00:00:28,820 --> 00:00:29,930 I'm going to build this. 9 00:00:32,550 --> 00:00:33,780 This is our new project. 10 00:00:34,870 --> 00:00:36,580 Right, and I'm going to run it. 11 00:00:39,430 --> 00:00:47,320 So I'll see debuggers ASTM 32, iSelect 36, and it's going to go to the DeBacker. 12 00:00:51,910 --> 00:00:52,630 It's open in. 13 00:00:56,640 --> 00:00:57,960 Now click here to switch. 14 00:01:01,690 --> 00:01:02,230 OK. 15 00:01:03,170 --> 00:01:09,830 So when I click this, I'll run and all of them are running the incrementing the same because they all 16 00:01:09,830 --> 00:01:11,120 have the same priority. 17 00:01:11,150 --> 00:01:12,740 OK, so what are we going to do? 18 00:01:12,740 --> 00:01:21,230 Is we going to let the orange task or thread change the priority of the. 19 00:01:22,420 --> 00:01:28,090 Of, let's say, the green thread to do this, we need to add something else to our threads. 20 00:01:28,510 --> 00:01:31,390 When we create our thread, our thread retains an idea. 21 00:01:31,420 --> 00:01:38,260 We need to store the idea of the thread somewhere so that we can use the idea of the thread to access 22 00:01:38,410 --> 00:01:40,920 or control the particular thread we are interested in. 23 00:01:41,290 --> 00:01:45,460 So I'm going to come up here and declare for variables of type. 24 00:01:45,460 --> 00:01:49,960 Always thread on the school, always thread. 25 00:01:50,410 --> 00:01:52,300 It is called actually Enniscorthy. 26 00:01:53,360 --> 00:01:57,170 That's the type, and we're going to have read it for our red thread. 27 00:01:57,380 --> 00:02:06,050 We're going to have green eyed creature of blue eyed green to have orange eyed. 28 00:02:07,860 --> 00:02:14,170 OK, so what are we going to do is whenever we create a threat, the ID is retained. 29 00:02:14,190 --> 00:02:18,730 We didn't make use of this ID in our first example, but now we're going to make use of it. 30 00:02:18,750 --> 00:02:25,110 I'm going to copy the Green ID and I'll come over here when we create the green thread is going to return. 31 00:02:25,110 --> 00:02:30,270 The ID will start here and I'm going to do the same for all of them. 32 00:02:30,660 --> 00:02:37,170 OK, this is for Red Threat is going to return the ID stories and read it over here. 33 00:02:38,160 --> 00:02:40,660 And I'm going to come down here. 34 00:02:40,710 --> 00:02:44,010 This one is for Orange Threat is going to return the ID. 35 00:02:44,010 --> 00:02:45,570 I'm going to store it over here. 36 00:02:48,400 --> 00:02:56,250 Range like this, and finally, Blue is going to return the ID and I'm going to store it in blue, ID 37 00:02:56,460 --> 00:02:57,120 like this. 38 00:02:59,220 --> 00:03:07,050 OK, so now that each threat has its ID stored, we going to use the thread ID to change the. 39 00:03:08,090 --> 00:03:14,840 Priority of the green threat, so I'm going to come to the orange threat when the orange threat executes, 40 00:03:15,380 --> 00:03:22,070 when it's executed was is going to set, let's say it's going to increase the priority of the green 41 00:03:22,070 --> 00:03:22,430 threat. 42 00:03:22,850 --> 00:03:28,250 So we come over here and the function we use, which we can find in our documentation. 43 00:03:28,250 --> 00:03:34,010 Remember the documentation I showed you how to open it for a reason or the functions can be found here. 44 00:03:34,250 --> 00:03:34,750 OK. 45 00:03:36,180 --> 00:03:48,240 Right, so we can come over here and we say always thread set priority, so this takes two arguments. 46 00:03:48,600 --> 00:03:53,640 The first argument is the idea of the thread, whose priority you want to set. 47 00:03:53,970 --> 00:03:56,130 We want to set the priority of green. 48 00:03:58,450 --> 00:04:04,510 Thread, so the next argument is the new priority you want to assign to it over here, we want to give 49 00:04:04,510 --> 00:04:06,460 it a priority above normal one. 50 00:04:06,790 --> 00:04:07,410 So I'll see. 51 00:04:07,430 --> 00:04:10,030 Always priority. 52 00:04:13,980 --> 00:04:22,980 Above normal one like this, and we saw the table where we had a list of priorities, OK, if you want 53 00:04:22,980 --> 00:04:24,540 to know more about the priorities. 54 00:04:26,090 --> 00:04:27,650 You can find them here. 55 00:04:29,920 --> 00:04:37,510 The states, the priorities, so there's always priority, non priority I do this is this priority is 56 00:04:37,510 --> 00:04:39,280 in descending order of magnitude. 57 00:04:40,060 --> 00:04:45,610 The the the higher the priority, the lower it is in the stable. 58 00:04:46,330 --> 00:04:47,740 OK, so that's priority. 59 00:04:47,740 --> 00:04:48,220 No more. 60 00:04:48,220 --> 00:04:48,610 No more. 61 00:04:48,610 --> 00:04:51,130 Plus one you say always priority number one. 62 00:04:51,670 --> 00:04:55,330 No more plus two is always priority normal two etc.. 63 00:04:55,600 --> 00:04:58,180 OK, and then there is always priority. 64 00:04:58,180 --> 00:04:58,570 Hi. 65 00:04:58,870 --> 00:05:01,380 I wonder how come they decided to name it this way. 66 00:05:01,630 --> 00:05:07,870 In any case, we're going to give this always priority one because our threads here have always priority 67 00:05:07,900 --> 00:05:08,410 normal. 68 00:05:08,620 --> 00:05:15,340 So we know after the execution of this line, the highest priority thread becomes the green thread. 69 00:05:15,800 --> 00:05:18,190 Let's see if this works. 70 00:05:18,670 --> 00:05:19,840 I'm going to click here to build. 71 00:05:26,460 --> 00:05:28,470 I think there is an anomaly. 72 00:05:29,820 --> 00:05:30,400 Huh? 73 00:05:30,760 --> 00:05:34,280 OK, over here, I misspelled priority. 74 00:05:35,220 --> 00:05:36,300 Click here to build again. 75 00:05:39,310 --> 00:05:40,120 It's built in. 76 00:05:42,070 --> 00:05:45,370 To build successfully, going to click here to download onto the board. 77 00:05:49,160 --> 00:05:50,000 It's open in. 78 00:05:53,370 --> 00:05:54,170 Click to switch. 79 00:05:57,760 --> 00:05:58,360 And. 80 00:06:00,330 --> 00:06:02,520 It's ready, so I'm going to click here to run. 81 00:06:04,610 --> 00:06:05,710 Let's see what happens. 82 00:06:07,180 --> 00:06:13,390 OK, so now we have just the green thread running across, indeed, we were able to change its priority 83 00:06:13,390 --> 00:06:17,790 in runtime using the OS thread priority search function. 84 00:06:18,400 --> 00:06:24,980 So that's all there is if you wish to change the priority in runtime using CMS is outsourced to API. 85 00:06:25,270 --> 00:06:26,440 It's as simple as this. 86 00:06:26,930 --> 00:06:27,430 OK.