COAL MIDTERM REVIEWER

Chapter 1-4

computer architecture

• those attributes of a system visible to a programmer

• direct impact on logical execution of a program

Instruction Set Architecture (ISA)

instruction formats, opcodes, registers, and data memory

computer organization

operational units and their connections

Organizational attributes

hardware details transparent to the programmer

function

operation of each individual component as part of structure

• data processing

• data storage

• data movement

• control

4 basic functions of a computer

data processing

data may take a wide variety of forms, and the range of processing requirements is broad

data storage

computer must temporarily store at least those pieces of data that are being worked on

data movement

computer’s environment consists of devices that serve as either sources or destinations of data

control

manages the computer’s resources

structure

the way in which the components are interrelated

CPU

controls the operation and performs the data processing functions

control unit

controls the operation of CPU

arithmetic and logic unit (ALU)

data processing function

registers

provides storage

CPU interconnection

some mechanism for communication

main memory

stores data

input/output

moves data between the computer and its external environment

system interconnection

provides communication among CPU

core

individual processing unit on a processor chip

processor

piece of silicon combining one or more cores

motherboard

main printed circuit board

chip

single piece of semiconducting material

integrated circuit

resulting product

charles babbage

invented calculator

1st Generation of Computers

used vacuum tubes for digital logic elements and memory

stored program concept

fundamental design and 1st used in the IAS computer

john von neumann

mathematician who proposed stored-program concept on a computer called EDVAC

electronic discrete variable computer

meaning of EDVAC

transistors

• solid-state device made from silicon

• invented at Bell Labs in 1947

microelectronics

small electronics

gate

implements a single boolean or logical function

memory cell

device that can store 1 bit of data

semiconductor memory

construction of the processor out of integrated circuit chips

fairchild

produced the first relatively capacious semiconductor memory

embedded systems

use of electronics and software within a product

internet of things (IoT)

expanding interconnections of smart devices ranging from appliances to tiny sensors

information technology

PCs, servers, routers, firewalls

operational technology

medical machinery, kiosks, non-IT companies

personal technology

smartphones, tablets, eBooks, wireless

sensor/actuator technology

single-purpose devices bought by consumers

embedded operating systems

• take an existing OS and adapt it for the embedded applications

• design and implement an OS intended solely for embedded use

cloud computing

a model for enabling ubiquitous, convenient, on-demand network access

cloud networking

the networks and network management functionality that must be in place

cloud service provider

maintains computing and data storage resources that are available on the internet

software as a service

provides service in the form of software

platform as a service

service in the form of platform

infrastructure as a service

provides virtual machines and other abstracted hardware 

hardwired program

process of connecting the various components in the desired configuration

• data and instructions are stored in a single read-write memory

• the contents of this memory are addressable by location

• execution occurs in a sequential fashion

3 key concepts of von Neumann architecture

• reads/fetches

• executes 

two steps of instruction processing

instruction cycle

processing require for a single instruction

• processor-memory

• processor-I/O

• data processing

• control

4 categories of instruction fetch and execute

processor-memory

data may be transferred from processor to memory vice versa

processor-i/o

data may be transferred to or from a peripheral device by transferring between the processor and I/O module

data processing

the processor may perform some arithmetic or logic operation on data

control

an instruction may specify that the sequence of execution is altered

• instruction address calculation (iac)

• instruction fetch (if)

• instruction operation decoding (iod)

• operand address calculation (oac)

• operand fetch (of)

• data operation (do)

• operand store (os)

instruction cycle states

instruction address calculation

determine the address of the next instruction to execute

instruction fetch

read instruction from its memory location into the processor

instruction operatioon decoding

analyze instruction to determine type of operation to perform

operand address calculation

determine the address of the operand

operand fetch

fetch the operand from memory

data operation

perform the operation indicated

operand store

write the result into memory or out to I/O

interrupts

a way to improve processing efficiency

multiple interrupts

a program may be receiving data from communications line and printing results

disabled interrupts

processor can and will ignore the interrupt request signal

I/O functions

exchange data directly with the processor

interconnection structures

a computer consists of a set of components of 3 basic types 

bus interconnection

communication pathway connecting two or more devices

system bus 

a bus that connects major computer components

data lines

provide a path for moving data among system modules

data bus

may consist of separate lines

width of data bus

key factor in determining overall system performance 

address lines

used to designate the source or destination of the data on data bus

width of the address bus

determines the maximum possible memory capacity

control lines

used to control access to and the use of data and address lines

control signals

transmit both command and timing information

timing signals

indicate the validity of data and address information

command signals

specify the operations to be performed

• memory write

• memory read

• i/o write

• i/o read

• transfer ACK

• bus request

• bus grant

• interrupt request

• interrupt ACK

• clock

• reset

typical control lines

memory write

cases data on the bus to be written into the address location

memory read

causes data from the addressed location to be placed on the bus

i/o write

causes data on the bus to be output to the addressed i/o port

i/o read

cases data from the addressed i/o port to be placed on the bus

transfer ack

data have been accepted from the bus

bus request

module needs to gain control of the bus

bus grant

module has been granted control

interrupt request

interrupt is pending

interrupt ack

pending interrupt has been recognized

clock

used to synchronized operations

reset

initializes all modules

quickpath interconnect (QPI)

• introduced in 2008

• a four-layer protocol architecture

• multiple direct connections

• layered protocol architecture

• packetized data transfer

characteristics of QPI

multiple direct connections

multiple components within the system enjoy direct pairwise connections to other components

packetized data transfer

data are sent as a sequence of packets

physical

actual wires carrying the signal

link

responsible for reliable transmission

routing

framework for directing packets