1. Chapter 2 Hardware Trends in Computing Systems
Generally classified into three groups
Mainframe computers
Midrange (mini) computers
Microcomputers (PCs)

2. Microcomputer Applications
Often referred to as personal computers
Many uses, styles, purposes
Workstations - High power PCs used for analytical processing, mathematical calculations, statistical analysis
Network Servers - Used to manage resources on a network (usually a Local Area Network)

3. Microcomputers (cont)
Personal Digital Assistants - Highly specialized and mobile devises
Use special software to allow for optical character recognition, touch pads, pen-based interface, etc.
This is the latest trend in communications devices

4. Multimedia Systems Personal computers with a variety of media devices
Allow for more robust displays, music, voice recognition and synthesis
More expensive than a traditional machine, but much more useful and capable

5. Network computers
Designed primarily for work situations where users access an Intranet (network using Internet technologies
These machines usually have little or no disk storage space
Main benefits are low cost, ease of upgrades, manageable

6. Computer terminals
Dumb terminal - No processing occurs at the terminal level. Usually associated with a mainframe or client/server system
Intelligent terminals - Have the capability to process at the local level (includes transaction terminals in grocery store, banks, department stores, etc)

7. Midrange Systems
Multi user systems that manage network traffic, file access, device management
More powerful than a personal computer
Less powerful than a mainframe
Less costly to purchase, operate, maintain
Most efficient when scope of use is narrow but processing needs are high

8. Midrange (cont)
Used largely in scientific research, process control situations, engineering (CAD, CAM, CAO)
Sometimes used as front end processors to aid a mainframe system
Good devices for telecommunications and network control (network servers)

9. Midrange (cont)
Can be used to host an Intranet, Extranet, Internet, or client/server system
Can be configured and programmed to operate virtually unaided
Do not require special climate controlled areas

10. Mainframe Systems
Physically larger than midrange, microcomputers, file servers
Can process more data and faster
Processing measured in MIPS (millions of instructions per second)
High storage capacity
Require climate controlled operating areas

11. Mainframe Applications
Support the information and processing needs of large corporations, government offices, military
Can handle vast computational tasks
Super-server for communications need of large client/server networks
Data warehousing

12. Supercomputer Applications
Used by major universities, multinational corporations, largest government divisions
Cooperative applications between countries
Use multiple processors (any of which could constitute as a mainframe)
$5million to $50 million cost

13. Components of a Computer System
It is important to understand the components of a computer as a system
Input > Processing > Output > Storage > Control

14. Input
Input devices allow for the feeding of data to the computer system
Keyboard/keypad
Touch screen
Light pens
Mouse
OCR
Voice activation

15. Processing
Central processing unit (microprocessor in a personal computer)
Performs three functions
Control unit
Arithmetic-Logic unit
Primary storage unit

16. Output Processed data in the form designated by the user
Devices include
video display (monitors)
Audio response
Printers

17. Storage
Used to store programs (computer instructions), data, processed information
Two types
Primary storage (main memory)
Secondary storage (magnetic disk, compact disc, magnetic tape)

18. Control
The control unit manages and interprets programs, transmission to other components of the system
Is part of the CPU
other part is ALU
CPU contains cache memory

19. Primary Storage Main memory - microelectronic semiconductors
Commonly known as RAM (random access memory)
Sometimes main memory can use ROM (read only memory)
Loss of data if power loss

20. Secondary storage Commonly known as permanent storage
Physical storage versus electronic storage
Support for primary storage

21. Multiple Processor Systems
Some systems use more than one processor unit
Several configurations
Usually splits the control unit and the logic unit

22. Multi Processor Configurations
Support Processor - Free up the main processor to execute program instructions (can be a math co-processor, video display controller or magnetic disk controller)
Coupled Processor - Used mostly to provide for fault tolerance
Parallel Processors - Execute instructions in sequence

23. cont
Massively Parallel Processors - Many processors aligned to execute hundreds or thousands of instructions at the same time
RISC - Reduced Instruction Set Computer
Uses less instructions

24. Conclude chapter 2 next week
Complete coverage of chapter 3 next week