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Hello fellas.

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Welcome back.

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So in this section we are going to focus on the program his perspective in terms of dealing with the

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architecture all microprocessors have a set of features that the programmer uses in most cases a program

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like yourself would not need to understand how the process is actually constructed such as the logic

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board transistors and things like that.

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You know from the programmers perspective what is necessary is a model of the device something that

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describes not only the way the process is controlled but also the features available to you as the program.

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Such as where we can data be stored and what happens when the machine detect invalid instruction where

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the registers are stacked etc. This is what is known as the program this module.

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This basically describes the architecture from the perspective of the programmer thinks that a programmer

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needs to know in order to write work in software for the hardware let's start by looking at the data

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types on the ARM architecture data in machine are represented as binary digits caught bits where one

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where one binary digits can be seen as either on or off zero or one.

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A collection of bits are often grouped together into units of eight code byte or larger or larger units

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Depending on depending on the maker of the device.

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So when describing instructions and data we normally talk in terms of the length.

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So we say things like 16 bits that two bits eight bits 64 bit extra.

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Most processors support 8 bit data type known as byte also support 16 bits data types known as the half

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word and 32 bits data types known as the word.

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There are other non common data types which we shall talk about when we start applying them in our code.

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But these are the common data types in the previous section we already learned that process is capable

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of running a classic instruction set which is that two bits in length and deform instruction set which

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is sixteen bit and lent in the next lesson we shall take a look at the various modes of the purchase

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all and I will see you in the next lesson.