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Hello, welcome back.

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In this lesson, we're going to see how to block a task writes.

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I'll copy the Lost Project.

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Or actually, I'll copy an earlier one.

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Let's see, we copy one of the earlier ones, I copy TASC Priority.

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Copy this.

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And then paste over here.

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And then I renamed this to know Martin.

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Blocking the task, you would wonder, why do we need to block the task?

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I would explain.

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OK, here we go.

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Yes, number 10, OK.

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Open this right, so.

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A task is either running or not running.

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We have to run in states, a task which is in the running states is ready to run.

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Maybe it's not got to its turn, but it is ready to run and not run in states.

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There is a state in there or a sub state of not running known as the blocked state and this blocked

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state.

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That task may be blocked because of something it is waiting for.

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A task is blocked when it's waiting for an event and this event can be a resource token or at time event.

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So the resource token can be a SEMAFO and you can think of a SEMAFO as a key.

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So when this happens, when the task requires an event to occur or a resource to be available before

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it continues its execution, it is placed in a blocked state.

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This type of block to states that we shall see now is going to be the block states.

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In which that time waits for a time U.S..

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This type of block states that we shall see now is going to be the block states in which the task waits

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for a tiny things to occur.

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So in effect, we shall see how to use that task delay function.

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So delay basically means wait for this particular amount of time.

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So delay wait for a timeout event so we shall see how to block tasks using the delay function.

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OK, so this is the project.

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Let's see.

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We created three tasks here.

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All of them have the same priority.

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OK, so if your copy hasn't to tasks with the same priority, I'm sure you have three tasks, all of

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them with the same priority.

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OK, and then.

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We have the task functions here, what we're going to do is we go into the field task, delay function

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V task, delay function takes takes as equipment.

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Right.

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So because we're not used to saying delay for this amount of takes, we're used to seeing how much time

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that delay show careful.

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Because of this, there is a macro which allows us to convert our time value into ticks.

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So what I'm going to do is I'm going to come over here or create this constant, I say constant, and

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this is off tick type.

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And then I'll call this variable.

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Score 50 times and together 50 times, I'm going to use the PD, EMS to tick's function.

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And over here or past 50.

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So this function is going to return the amount of ticks required for 50 miles and it's going to straighten

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this variable for me.

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OK, so what I'm going to do is I'm going to go to all of our task functions and then I'll let one of

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them delay for what time is, let's say red.

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I'll save task.

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DeLay underscore school tm's.

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OK, so let's see how that works.

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Click here to build.

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And then click here to go to debug.

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A select number 10 over here.

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OK, over here.

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uSwitch.

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These ones do not exist because this project has got these.

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This global variables.

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I'm going to click here to run, as you can see, Red is not running as much as the others because red

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has this delay.

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Red is often blocked.

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Is blocked for 50 times because of this, so this is the blocked states rights, so this is precisely

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if you want to precisely this is the way to achieve that.

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OK, so this or the risk, this or the risk for this lesson and I'll see you in the next lesson, have

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a nice day.