Summary
Summary 1.1 - systems architecture
- Course
- Institution
GCSE OCR COMPUTER SCIENCE J277 1.1 - SYSTEMS ARCHITECTURE 1.1.1 Architecture of the CPU, 1.1.2 CPU performance, 1.1.3 Embedded systems
[Show more]
Seller
Follow
harinisaseetharan
Content preview
iTALU <--
-- t
Fc
ACC
HAT
MD
Mq,ia r,^owtoyu
Ce*u.
B-Os4)
'
The CPU is the Central Processing Unit. It is used to execute instructions stored in memory using the
fetch-decode-execute cycle. The CPU contains the ALU, CU, the cache and several registers.
,rckvi\
The Control Unit (CU)
Ao.odo, - -> manages the fetch-decode-execute cycle
Ac.oAos ct vv1
P.o 1' ) controls the flow of data inside the CpU and outside the CpU
(ttslwt tcki crnS
The Arithmetic and Logic Unit (AtU)
; carries out arithmetic calculations such as addition/subtraction Co*,? a.StOr,S S\lr CU\ ctS
) carries out logical calculations such as AND/OR/NOT
) contains the accumulator
The cache
) fast memory in the CPU. slower than registers but faster than RAM
) stores regularly used data
) Iow capacity, expensive compared to RAM
The fetch-decode-execute cycle
) memory address is copied from the program counter to MAR
, the instruction in the MAR address is copied to the MDR {el-c[.
) increment the program counter
; instruction in MDR is decoded by control unit
o.nol. tltert s{ noLs cqyr[',,ol g',q *nc1ls hc
Ju.o r(q o) o.+Sio(e |Lta ccannpvtaerrtt witt^i.,,
) the instruction if executed tLc cPU [t^q[^eeob k ac\-
h ho\Ainfonvlahanr un""doJ for tt-r C?U lowa/c,t^olAs ( Woi(ic 1ie.n o{ ,*[*,.,tatou
aru\sQd'
The Von Neumann architecture describes a system where the CPU runs programs stored in memory.
Registers temporarily hold bits of data needed by the CpU
) Proglam Counter (PC) - holds the memory address of the next instruction to be processed
; Accumulator (ACC) - results of operations carried out by the ALU are stored
; MemoryAddress Register (MAR) - holds the memory location of the current instruction to be fetched
-)Memory Data Register (MDR) - holds data when it is fetched from memory or data that is waiting to be
written to memory
t)lxprl llrire
(entrrl Pmte*ciry Unit {CFU)
Control Uni!
It*6i*tenr
i*arty Ar*h*
r Aritln*fir & totic
I uilr (Arul
T
Iryril l}firc }itcnxFf :
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller harinisaseetharan. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $9.89. You're not tied to anything after your purchase.
Can Stuvia be trusted?
4.6 stars on Google & Trustpilot (+1000 reviews)
81033 documents were sold in the last 30 days
Founded in 2010, the go-to place to buy study notes for 14 years now