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Apart from the information you get from this cause it would be worth taking a look at some reference

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documents off the board like the the microcontroller data sheets for instance is fairly standard in

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a new hardware you buy you have to take some time to look through the data sheet as we go through this

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course.

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Yes we're going to go through the data sheets together to extract just what we need to worry that data

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sheet is quite large.

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You don't need to memorize it.

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You don't need to learn at all.

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It's just a reference manual like a sort of dictionary if you want to do something.

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You go and check in the data sheet.

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So it's worth downloading and having it on your computer.

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Another one is DTV see Launchpad User's Guide this.

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Also worth a read.

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And yes finally we are ready to write our first assembly code.

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How excited are you.

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I'm certainly excited.

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I remember the first time I wrote assembly.

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Yes.

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So our first program is fairly simple.

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It's called the read on what this diocese the read LCD.

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Remember we have the our GDP.

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We have green blue and green LCD already on our board.

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What this program would do is keep that red LCD on.

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It doesn't blink.

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Remember when you buy the board there is a program that makes the lights blink on this first program

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we're going to write.

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It's going to keep the lights on and we're going to write it in assembly.

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Then after that we improve these programs that by step we start adding things to it.

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And a well-structured program must begin with a requirements document.

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Yes I think it's important to have a requirement documents for every program.

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So we'll start this first one by trying to write down some requirements analysis for this program.

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And as we go on this a very simple program in fact we wouldn't we don't even need to write such a document

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for it.

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But I think it's a good practice to do.

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Yes.

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So we just go through some of the things we write and the requirement documents have the requirement

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document enforced determine determine and the needs of the system through asking questions they see

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some of the questions we can ask what is the opportunity of this project.

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Yes it is to design build and test a system that turns on the red LCD.

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How will the project be developed.

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The program will be written in color youth vision develop to use an at TVC launch part.

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How will it fit into existence systems.

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The read on program will be callable from systems having to see microcontroller.

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That's good.

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What will this system do precisely.

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Yes the system will start by setting up the required pieces on the board and then into an infinite loop

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that keeps the red LCD turned on.

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So this a fairly fair.

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Very very short requirement document.

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But I know you understand based on this if you write in a big up program you would know the questions

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to ask.

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This is just to give you what such a requirement document would.

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Now let's take a look at the projects set up every call you Vision Project contains two paths that when

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you create a new project comes along with it and these files are the same file written in C and then

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assembly.

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And what this file should do is that this sets up the starting point of the program.

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They have what we call a reset handler the block of code that is it's run every time you press the reset

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button.

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Also this file is outlined a stack size and a heap size.

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I know we've not talked about stuck in a heap.

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We'll talk about them later.

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I just wanted to know the functions of the startup files and without these files you cannot compile

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your program you would receive error messages.

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So when you create your project you get these files.

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They also contain the reset factor and all interrupt vectors.

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We'll talk about interrupt later as we mentioned earlier the reset handler runs every time the reset

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button is pressed on your microcontroller board.

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And what this does is that it jumps straight to the starting point of your program and in C program

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in code written and c the start point as to main function.

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So what this means is that if we're right in our program entirely in assembly and we want the program

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to start from the assembly side we would have to go to the reset handler and change the starting point

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to the starting points that we give our program.

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We would see this when we create our program.