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Hello, welcome back.

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In this lesson, we're going to see how to configure a task to execute periodically.

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Now we said tasks execute based on the time quanta that is set in the configuration of the art Toscano,

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whether it is 10 milliseconds, five milliseconds, etc..

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What this means is that each task in a state where the tasks have the same priority, each task would

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execute for this amount of time.

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And then once this amount of time is exhausted, the next task would execute and then the next one and

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then you come back to the the first one again.

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This time, what if what if we want a task to execute, see?

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Every 50 milliseconds, you don't want to execute for this long, but you wanted to execute 150 milliseconds,

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pass the statement out different.

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Remember, we're not saying you wanted to execute for 50 milliseconds, but you wanted to execute every

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15 milliseconds, in a sense, wanted to be parodic, wanted to execute at a fixed frequency.

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Wandy task to start executing at a fixed frequency.

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We're going to see how to achieve that, using our using a function that we shall work with here, this

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function as part of the delay function.

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It's similar to the the delay function we saw earlier.

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This function is called the task delay until function.

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So you're basically saying delay until this amount of time.

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So without talking much, I'm going to go ahead to make a copy of project number 10 over here.

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I'll copy number 10 or paste over here and I'll call this eleven and then I'll call this executing tasks

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periodically.

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OK, and it's opened, I'm going to close these ones here.

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When pundits call over here, so over here in that seat over here.

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OK, so what are we going to do?

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Is we going to nominate Blue to execute periodically?

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In this new project, I'm going to delay I'm going to delete this feature delay if I'm right, and I'm

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going to come to blue here and inside blue, I'm going to have a number of local variables because it's

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simply I this is, um.

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Do we need.

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I hear.

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We don't need our loop, so we can we can forget about I am going to create a ticker tape.

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Remember, we created a static type variable, which is just an integer type.

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If you go deeper, you realize of what you intended to underscore.

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So for readability sake, this has been given to the tick tock, just like we created our own we created

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a task profile here, which is also you intended to underscore t so I'm going to create a tick time

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variable.

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It's also a bit like tick tock, tick, tick type over here.

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Let's go to you and then I call this X last.

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Wake up or last week time, the last time he was awake, essentially, and then I'm going to grab this

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this bit here.

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Remember, the functions that delay or the block functions require you to pass takes as an argument.

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Because of that, we have this macro that allows us to convert our time to Tick's.

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OK, this time I'm going to call this.

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Spirit.

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And then 500 M is a past 500 here, so we would want this function or this task to execute every five

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hundred milliseconds.

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OK, so now we're going to see gets us the current take account.

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So I'll see over here X to ask.

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Get to take account.

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Like this, and it's going to be stored in this variable, right, once that is done, we're going to

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come over here.

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Our function v task to lay onto V task delayed until it takes two arguments.

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It takes to the last wake up time and then the period.

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OK, so we're going to see if your task is the name of the function V task delay until.

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The first argument is the address of this rebel and the reason we passed the outrace of this rebel rather

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than simply to develop, was that last week up time is going to be updated automatically.

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So this variable is going to be updated after then after execution when this line executes the new last

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week.

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Time would be stored in this variable.

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So it's not going to be the old one that we read from here.

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OK, so the next argument is the period XP right over here.

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Right.

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So let's build and see the click over here to build.

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And then quicker to get onto the boat.

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Number 11 here.

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Then OK.

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Switch.

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Then let's see, so blue is the one expected to execute periodically.

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Let's see.

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We place this in blue.

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OK, so let's run and see.

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Blue.

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OK, so every 500 blue kicks in its rich ones.

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Right.

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So this is it.

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So in some applications, you require a task to execute with a precise period or precise frequency.

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This is one of the ways to achieve that.

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Another way to achieve that, of course, would be to create a hardware interrupt using a timer.

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Because with a hardware timer, you can come a time to arm, to create and interrupt every 500 times

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or 50 times or 100 times, right.

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But in an amateur system, if you need an artist's version of that, you can use the V task delay until

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function over here.

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So this all there is and I'll show you the next lesson of the.