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Hello.

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Welcome back.

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So in this section we're going to talk about armed design philosophy and the risk architecture and this

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very lesson we're going to talk about a risk design philosophy.

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But before we do that I want to spend some time to give a short introduction on arm as a company so

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obvious a company based in Cambridge U.K. arm is a design firm that do not manufacture any hardware

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or silicon.

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All they do is they come up with the designs of the architecture and then they sell the license to companies

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such as Apple.

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Some song while we Qualcomm Texas Instruments extra.

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So this is very key when you hear of the armed company don't produce any hardware digits.

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Design is the design the arm the architecture and then sell it out as a license to arm all the various

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brands that we know.

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So let's move on so risk stands for reduced instruction set.

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And this is sharply different from Sisk which stands for the complex instruction sets as we shall see.

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And this course proves the source used to risk architecture while internal processes use complex instruction

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sets.

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And if you don't know what instruction sets means don't worry about this for now.

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We have sections dedicated to instruction sets for now.

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You can think of instruction set as this set of instructions in a language.

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A good analogy will be the set of words in the English language all the set of words in the Chinese

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language etc. like we do in our daily lives.

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We use the set of words available in English to construct sentences to convey meaning to the person

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we are talking to in the same way we use the instructions available in a particular instruction set

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off the computer micro architecture to convey meaning to the computer hardware the risk design philosophy

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is aimed at simple but powerful instruction that execute within a single cycle a Thai clock speed risk

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focuses on reducing complexity of the instruction is performed by hardware because it is easier to provide

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greater flexibility and intelligence and software write it down in hardware.

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As a result greater demand is placed on the compiler risk philosophy is implemented with four card in

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all design rules in mind.

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One there has to be reduced number of instructions and each instruction must be executed in a single

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cycle to make sure every process a cycle executes on instruction.

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Instructions are executed in parallel using pipelines which we shall talk about later.

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This is important because in Sisk there are times the process just runs.

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While waiting for data or instruction to be ready for memory also risk.

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Machines provide a large number of general purpose registers in a register that can eat up the data

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or address registers our first local stores that we do processing and we shall look out registers later.

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SISK architecture registers how dedicated purposes therefore do you know as flexible.

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Also in risk architecture the process operates on data held in the registers.

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This is one of the other reasons risk processes are capable of one instruction per cycle.

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The next lesson which I'll look at is how uses risk architecture combined with their own design philosophy

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to design powerful process laws.

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I'll see you in the next lesson.