Lakhasly

Computer Architecture Computer Organization oComputer Architecture oAttributes of a system visible to the programmer oHave a direct impact on the logical execution of a program oArchitectural attributes include: oInstruction set, number of bits used to represent various data types, I/O mechanisms, techniques for addressing memory oComputer Organization oThe operational units and their interconnections that realize the architectural specifications oOrganizational attributes include: oHardware details transparent to the programmer, control signals, interfaces between the computer and peripherals, memory technology used

• IBM System ?A control unit manages the computer's resources and orchestrates(coordinate) the performance of its functional parts in response to instructions Structure

There are four main structural components of the computer: ?New models are introduced with improved technology, but retain the same architecture so that the customer's software investment is protected ?CPU - controls the operation of the computer and performs its data processing functions ?System Interconnection - some mechanism that provides for communication among CPU, main memory, and I/OIBM System/370 architecture ?Included a number of models ?Hierarchical system ?

Computer Architecture
Computer Organization
•Computer Architecture
•Attributes of a system visible to the programmer
•Have a direct impact on the logical execution of a program
•Architectural attributes include:
•Instruction set, number of bits used to represent various data
types, I/O mechanisms, techniques for addressing memory
•Computer Organization
•The operational units and their interconnections that realize the
architectural specifications
•Organizational attributes include:
•Hardware details transparent to the programmer, control signals,
interfaces between the computer and peripherals, memory
technology used

• IBM System
  ■ IBM System/370 architecture
  ■ Was introduced in 1970
  ■ Included a number of models
  ■ Could upgrade to a more expensive, faster model without having to
  abandon original software
  ■ New models are introduced with improved technology, but retain the
  same architecture so that the customer’s software investment is
  protected
  ■ Architecture has survived to this day as the architecture of IBM’s
  mainframe product line
  370 Architecture


• Structure and Function
  ■ Hierarchical system
  ■ Set of interrelated
  subsystems
  ■ Hierarchical nature of complex
  systems is essential to both
  their design and their
  description
  ■ Designer need only deal with
  a particular level of the system
  at a time
  ■ Concerned with structure
  and function at each level
  ■ Structure
  ■ The way in which
  components relate to each
  other
  ■ Function
  ■ The operation of individual
  components as part of the
  structure

Function
■ There are four basic functions that a computer can perform:
■ Data processing
■ Data may take a wide variety of forms and the range of
processing requirements is broad
■ Data storage
■ Short-term
■ Long-term
■ Data movement
■ Input-output (I/O) - when data are received from or delivered to
a device (peripheral) that is directly connected to the computer
■ Data communications – when data are moved over longer
distances, to or from a remote device
■ Control
■ A control unit manages the computer’s resources and
orchestrates(coordinate) the performance of its functional parts
in response to instructions
Structure
+
There are four
main structural
components
of the computer:
✦ CPU – controls the operation of
the computer and performs its
data processing functions
✦ Main Memory – stores data
✦ I/O – moves data between the
computer and its external
environment
✦ System Interconnection – some
mechanism that provides for
communication among CPU,
main memory, and I/O