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We are going to demonstrate how to program the outputs compare going to demonstrate the output to compare

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functionality.

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What we're going to do is we're going to initialize all our four entities and we're going to let them

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go on and on a specific times using outputs compare.

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And for those of you who are not familiar with output compare output compare the ability to trigger

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an output based on a particular timestamp.

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And we're not going to be using if else in the state is going to be that event will result in a hardware

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interrupt also known as outputs compare interrupt.

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So we're going to set a particular timestamp.

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We're going to say red should be should come on after 50 milliseconds Irene should come on after 30

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milliseconds Quinn should come on after let's say 100 milliseconds and the cycle continues.

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And this this is turned on and off using hardware interrupts anyway if you need more information on

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output compared to drugs just in their message or legal questions below.

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So we're going to demonstrate that now and I'm going to come to Cuba makes and I'm going to create a

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new project.

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I'll come over here.

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You project and I select my board.

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The board is that disco board that's the f 4 and this is my board over here and once it's generated

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what I want to do is clear all pins I click over here to clear the pins and what I want is I'm going

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to initialize my abilities to work with a timer so I know my entities are connected to PD 12 13 14 and

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15 I just click over here and set it to output compare I can set it to timer for Channel 1 cost us the

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timer it's got access to and I click this this one is connected to time off for Channel 2 so I just

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use that time I trust.

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So if the if the particular GPA pin had no access to the time a module wouldn't have been able to use

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the output compared in this case so I click this and this yellow marks means the initialization of this

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is incomplete that that is why it's not green mean and it requires further initialization of configuration

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before we complete.

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So to do that I'm just going to come over here to the time a module which time this time or force or

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click time of four over here and what I want is to enable the channel one as an output to compare like

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this and then to enable channel to us all to compare as well.

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Same for Channel 3 Channel 4 and what I want is to provide a clock source here I'm going to use the

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internal clock here.

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Now I'm set I'm set.

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What I have to do next.

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Of course is to enable mighty Barker or select overhead and choose the serial wire and I'm set to know

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what I have to do is go and configure my time on the pre scalar value in the period or the frequency

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of the timer.

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So to do the I've just come to configuration and I would just keep my default clock set in here.

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So now we have to configure our timer and to do that.

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We just click over here and like we did before we have to set a pre-schooler of the timer currently

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the timer is in the second unit we want to bring the unit into milliseconds to do that.

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We know our timer clock is forty eight megahertz from the clock tree over here as we can see is 48.

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So to bring this down to milliseconds we have to divide it by four thousand eight hundred

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configuration timer so I put four thousand eight hundred here like this and we want our counter period

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to be one second.

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So I put 1000 here.

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If you don't understand the origins of of these numbers do send me a message or leave your question

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below.

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And after that we wonder countermove to be up count mode.

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And now we have to configure each channel over here.

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I've configured them already I have output to compare Channel 1.

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And I wonder more to be toggle on much select toggle on March.

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And the power should be 200 m M.S. meaning I want this particular channel to toggle every one fifth

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of a second every one fifth of it.

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Second I want this channel to toggle and four channel to every half a second because I've got 500 here.

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And remember a second is equal to 1000.

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So every half a second I want Channel 2 to Tokyo and every 3 fourth of a second I want to channel 3

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to toggle and I want Channel 4 to toggle every second.

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So each channel you changed a mode to toggle on March and then you set the pulse rate so there's the

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pulse rate of each channel.

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So once that is done we move on to the next configuration.

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We can leave everything else the same click okay here and it's all set.

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Next what we have to do is generate our code and I'll just come over here and click to generate and

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I'll give my project a name timer on the score article compare my school output compare and then I'll

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choose my two chain which is to call in decay version 5 I'll select this here and everything else is

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the same so click okay and it generates and then it's done and then I'll click over here to vote in

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the project and once it is open I will just rebuild to bind everything

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and once I start I'll just set my debugger to run on reset just by clicking over here then taking this

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here.

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Okay then.

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Okay so I just explained this this one here and check the main file and the only thing I have to do

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here is at the time of Chanos and I set my sights on it would kick in and do its work.

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What I want to do is I want to come to functions and see which particular function I need for this so

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I'll click over here to see all the options I've got for this particular module.

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So let's see what we need in order to be able to start on the output compare.

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We need this particular API here.

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Hall time output to compare starts.

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Let's double click and see what it takes.

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As you can see these documents the various parameters here.

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It takes the time I know.

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And then it takes it points to the timer structure.

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So this one here takes appointed to the timer structure.

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This takes the time which I know so let's just copy this function and go and customize it to start our

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article with compare to put us here and of course I'll delete this.

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We already know our time up on the structure.

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Is this defined over here as h t n h in 4.

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I just copy this and then I'll bring it here like we saw it.

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It takes this argument with Ampersand sign like this.

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I don't believe this.

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And then no one can put the China no overhead

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I can just say time on a school China one.

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Then I've started China one I can copy and paste for the other three put is this for this and I could

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just change this too.

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And in fact that's all we need to do we just need to start out the timer and we don't need to do anything

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else.

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Let's deal with the code and download on top board and we're building No.

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And as you can see the LCD is Blinken in the sequence we programmed the pose is blinking in the time

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period we give each the D.

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So this is the use of output compare this how easy it is to create such code in this example we just

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use an LCD as output but like I said if you want to understand details of this how output compare works

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the internals just send me a message or just leave your question below this.

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This course is he had to teach you how to rapidly use the SDR SDM Cuban mix to prototype your work and

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suggest generates code with it we don't go into the details of the pair for development but if that

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is something you are interested in I'm always willing to help.

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I'll see you in the next lesson.