Prezentace

1
Department of Computer Science Faculty of Civil
Engineering, Brno University of Technology
Information Technology 1
Inside the Personal Computer
2
Repetition

• A computer is a data processing machine which
  isoperated automatically under the control of a
  listof instructions (called a program) stored in
  itsmain memory.
• Conventional digital computers have a common
  formthat is attributed to von Neumann.
• Von Neumann computers are general
  purposecomputers.
• Data and instructions are both storedin the main
  memory.
• Central processing unit (CPU, processor) contains
  thecontrol unit that coordinates the execution
  of instructions, and the arithmetic-logic unit
  that performs arithmetic and logic operations.

3
Repetition
Control unit
Arithmetic-logic unit
Registers
CPU
Instructions
Data
Main memory (operational)
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Repetition

• The main (operational) memory is used to
  storeprogram and data which are currently
  manipulatedby the CPU. Main memory is fast and
  of limited size.
• The peripheral (secondary) memory provides
  thelong-term storage of large amounts of data
  and program. It is relatively slow and of very
  large size.
• The most important characteristics of a memory
  arespeed (access time and data transfer rate),
  size and cost, which are mainly constrainedby
  the technology used for its implementation.
• Facts
• The faster memory is, the greater the cost/bit
  is.
• (The larger memory is, the slower is it.)

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The Anatomy of a PC Key Concepts
RAM An acronym for Random Access Memory. It is
random because any of the bits or bytes
resident in RAM can be accessed
nonseqeuntially. RAM is memory that can be both
read and written to. The information stored in
a semiconductor RAM will be lost when electrical
power is removed. ROM An acronym for Read-Only
Memory. We cannot write new data to those
memories. There are several subtypes of ROM
classical ROM, PROM (Programmable
ROM), EPROM (Erasable PROM), EEPROM
(Electrically EPROM), Flash-EEPROM.
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The Anatomy of a PC Key Concepts
BIOS An acronym for Basic Input/Output Sytem.
A collection of software codes built into a PC.
BIOS is stored in ROM (Flash-EEPROM usually)
chip on the motherboard. Boot The process that
takes place when a PC is turned on and it
performs the routines necessary to get all the
components functioning properly and then load
the operating system. POST An acronym for
Power-On Self-Test, a procedure the computer
goes through when booting to verify that the
basic components of a PC are functioning.
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The Anatomy of a PC Key Concepts
CMOS An acronym for Complementary
Metal-Oxide Semiconductor a term that
describes how a CMOS chip is manufactured.
Powered by a small battery, the CMOS memory chip
retains crucial information about what hardware
a PC comprises even when the power is turned
off. Clock A microchip that regulates the timing
and speed of all the computers functions. The
chip includes a crystal that vibrates at a
certain frequency when electricity is applied to
it. The speed of clocks and therefore
computers is expressed in megahertz (MHz) or
gigahertz (GHz). Thus a PC may be desribed as
having a 1.2 GHz processor, which means that the
processor has been designed to work with a clock
chip runnig at that speed.
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Types of RAM

• DRAM (Dynamic Random Access Memory)
• For years, the most common type of main RAM.
• Dynamic refers to the memory's method
  ofstorage basically storing the charge on a
  capacitor, which leaks the charge over time and
  must be refreshed about every thousandthof a
  second.
• SRAM (Static Random Access Memory)
• RAM that, unlike DRAM, doesn't need to have
  itselectrical charges constantly refreshed. SRAM
  isusually faster than DRAM but more expensive.

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Memory Modules

• Memory module is a small circuit board with the
  memory chips (RAM). It uses less board space and
  it is more compact.
• SIMM (Single In-Line Memory Module) 30- or
  72-pin
• DIMM (Dual In-Line Memory Module)
• RIMM (Rambus In-Line Memory Module)

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Memory Modules contd
SIMM (72-pin)
DIMM
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Cache Memory

• The speed of the main memory is relative slow
  with respect to the today's processors.
• A cache memory is a small, very fast memory
  that retains copies of recently used
  information from the main memory.
• Memory caching is effective because the running
  programs access the same data or instructions
  over and over.
• Cache capacity is much smaller than main memory
  (about 1/128 1/32 of the main memory
  capacity).
• Cache memory operates transparently to the
  programmer, automatically deciding which values
  to keep and which values to overwrite.

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Cache Memory contd

• Primary cache (Level 1, L1 cache) is built into
  the processor chip with a zero wait-state
  (delay) interface to the processor's execution
  unit, it is limited in size.
• Secondary cache (Level 2, L2 cache) can be
  found on the motherboard.

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CPU (processor, microprocessor)

• CPU Central Processing Unit
• often called the brains of a computer
• CPU is a tight, complex collection of
  transistors arranged so that they can be used
  to manipulate data
• most operations of the computer are handled by
  the processor
• processor manufacturers Intel, AMD, Cyrix

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CPU cont'd

• According to Moore's Law formulated in 1965 by
  Gordon Moore (co-founder of Intel), the number
  of transistors per integrated circuit would
  double every 18 months. Moore predicted that
  this trend would hold for the next ten years. In
  fact, as the graph illustrates, Intel has
  managed to doggedly follow this law for far
  longer. In 1978 the 8086 ran at 4.77 MHz and had
  less than 30,000 transistors. By the end of the
  millennium the Pentium 4 had a staggering 42
  million on-chip transistors and ran at 1.5 GHz.

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CPU cont'd
Source www.pctechguide.com
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Processor Registers

• Registers are very fast temporary storage
  devices typically used to hold intensively
  used data and intermediate results.
• The set of registers within the CPU represents
  the top level of the memory hierarchy.
• User Visible Registers
• Can be accessed by programmers.
• They are often called general-purpose registers.
• Control and Status Registers
• Used by the control unit to control the
  operation of the CPU not directly accessible
  by the programmer.

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Stack

• A list of data elements, with the restriction
  that elements can be added or removed at one
  end of the list only. This end is called the
  top of the stack and the other end is called
  the bottom.
• Placing a new element on top of the stack is an
  operation called push removing the top
  element is called pop.
• LIFO Last In First Out

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Generations of Processors
Data/ L1 Memory
Internal Type/Generation Year Address
Cache Speed Clock Bus KB MHz
MHz 8086/First          1978 16/20
bit None 4.77-8 4.77-8 8088/First 1979 8/20
bit None 4.77-8 4.77-8 80286/Second 1982 16/24
bit None 6-20 6-20 80386DX/Third 1985 32/32
bit None 16-33 16-33 80386SX/Third 1988 16/32
bit 8 16-33 16-33 80486DX/Fourth 1989 32/32
bit 8 25-50 25-50 80486SX/Fourth 1989 32/32
bit 8 25-50 25-50 80486DX2/Fourth 1992 32/32
bit 8 25-40 50-80 80486DX4/Fourth 1994 32/32
bit 88 25-40 75-120 Pentium/Fifth 1993 64/32
bit 88 60-66 60-200 Pentium
MMX/Fifth 1997 64/32 bit 1616 66
166-233 Pentium Pro/Sixth 1995 64/36 bit 88 66
150-200 Pentium II/Sixth 1997 64/36
bit 1616 66 233-300 Pentium
II/Sixth 1998 64/36 bit 1616 66/100
300-450 Pentium III/Sixth 1999 64/36
bit 1616 100 450-600 AMD Athlon/Seventh 1999 6
4/36 bit 6464 100-200 500-600 Pentium
4/Seventh 2000 64/36 bit 128 100 1.4 2 GHz
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Block Diagram of the 8086 Processor
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AMD Processors
Athlon
Duron
K6-2
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Motherboard (mainboard)

• The main circuit board inside the PC which holds
• processor,
• main (operational) memory RAM,
• CMOS memory (it is used to store basic
  information about the PC's configuration)
• BIOS stored in ROM (usually Flash-EEPROM)
• integrated floppy drive and hard drive
  controller
• expansion slots (ISA, PCI, AGP, ...)
• I/O ports and other interfaces (parallel and
  serial port, USB, )
• connectors to connect other parts of a computer
  (keyboard, small speaker, reset switch,
  power LED, CPU fan, )
• ...
• The above-stated information is dependent on the
  type of motherboard.

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Motherboard (mainboard) cont'd
Graphics card, soundcard, faxmodem, etc. canbe
integrated on the motherboard (All-In-One
motherboard).
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Expansion (I/O) Buses

• peripherals are connected to the I/O buses in
  various ways, primarily through connectors
  directly on the motherboard and through
  different interfaces such as expansion cards
• I/O bus depends on the type of processor
• slots (connectors of I/O bus) are placed on the
  motherboard
• different types of I/O buses
  ISA, MCA, EISA, VL-Bus, PCI, AGP

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ISA Expansion Bus

• ISA Industry Standard Architecture (also
  AT-Bus)
• the oldest, slowest and soon to become obsolete
  I/O bus
• designed for 80286 processor
• specifies a 16-bit transfer driven by a 8 MHz
  clock
• It has a theoretical data transfer rate of up to
  16 MBps. Functionally, this rate would reduce
  by a half to 8 MBps since one bus cycle is
  required for addressing and a further bus
  cycle for the 16-bits of data. In the real
  world it is capable of more like 5 MBps -
  still sufficient for many peripherals - and the
  huge number of ISA expansion cards ensured its
  continued presence into the late 1990s.

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Block Diagram of the ISA Architecture
(simplified)
ISA Bus
Processor
16-bit slots
ISA controller
System bus
8-bit slots
Main memory
L2 cache
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PCI Expansion Bus

• PCI Peripheral Component Interconnect
• designed for 80486 a Pentium processors
• in its original implementation PCI ran at 33
  MHz, it was later raised to 66 MHz
• theoretical throughput to 266 MBps (33 times
  faster then ISA)
• it can be configured both as a 32-bit and a
  64-bit bus
• supports the PnP standard (Plug and Play)

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Block Diagram of the PCI Architecture
(simplified)
ISA Bus
Processor
PCI/ISA Bridge
ISA slots
PCI slots
CPU/PCI Bridge
System bus
PCI bus
Main memory
L2 cache
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PCI Slots
ISA Slots
Source www.howstuffworks.com
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AGP

• AGP Accelerated Graphics Port
• designed for Pentium II processor
• used for graphics cards only
• significantly speeds the performance in graphics
  app's (3D graphics, texture mapping and so on)
• operates at the speed of the processor bus
• AGP 1x (264 MBps), AGP 2x (528 MBps), AGP
  4x (1056 MBps)

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Block Diagram of the AGP Architecture
Source www.pctechguide.com
31
AGP-based Graphics Card (example)
Source www.howstuffworks.com
32
Parallel Port

• is most often used to connect a printer
• some drives (e.g. ZIP) and other peripherals
  (e.g. scanner) may piggyback on the parallel
  port
• Canon connector, 25-pin female, marked LPT or
  PRN, (interface Centronics)
• standard IEEE 1284 provides bi-directional
  communication and faster data flow
• Compatible Mode (Centronics), Nibble Mode,
  Byte Mode, EPP (Enhanced Parallel Port) Mode,
  ECP (Extended Capabilities Port) Mode
• EPP mode is mostly used

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Serial Port

• is most often used to connect a mouse or a modem
• Canon connector, 9- (or 25-) pin male, marked
  COM or RS 232
• slower than parallel port
• today's computers usually use a mouse that
  connects to a PS/2 port (connector)

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USB

• USB Universal Serial Bus
• up to 127 peripheral devices can be connected
• supports fast data transfer rates
• along with the signal USB carries a 5 V power
  supply so small devices, such as hand held
  scanners or speakers, do not have to have
  their own power cable
• was designed to be user-friendly and it is
  truly PnP

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Motherboard SL-77KV
Specification
www.soltek.com.tw Processor AMD Athlon
Chipset VIA APOLLO KX133, FSB 200 MHz, AGP 4x
Memory 3 x 168-pin 3.3V DIMM Sockets,
Supports 8MB to 768MB (maximum) DRAM Size, PC
133 compliant Cache Memory Built-in to AMD
Athlon Processor Module On-Board EIDE 2 x
PCI Bus Master UATA 33/66 IDE ports (up to 4
ATAPI Devices) Supports for PIO Mode 3, 4,
UATA 33/66 IDE ATAPI CD-ROM
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Motherboard SL-77KV cont'd
On-Board Super I/O 1 x Floppy Port, 2 x
serial ports (high-speed 16550 FIFO UART Ports),
1 x Parallel Port with EEP/ECP/SPP
Capabilities, PS/2 Mouse connector, Keyboard
connector, 4 x USB Ports Expansion Slots 1
x AGP Slot, 1 x AMR Slot, 5 x 32-bit PCI Bus
Master Slots, 1 x 16-bit ISA Slots Form Factor
ATX Form Factor (190mm x 305mm) BIOS AWARD
Plug-and-Play BIOS Supports Advanced Power
Management Function Flash Memory for easy
upgrade Other Features Supports AGP4x, PC 133
compliant, Ultra ATA/66, AC'97 Audio
Function, H/W Monitor
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Motherboard SL-77KV cont'd
38
Motherboard SL-77KV cont'd
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Power Supply

• converts the AC input (230 V) to lower DC
  voltages (3.3 V, 5 V, 12 V, 5 V, 12 V)
• the 3.3- and 5-volts are typically used by
  digital circuits, while the 12-volt is used
  to run motors in disk drives and fans
• the main specification of a power supply
  is in watts (usually about 250 W or more)

Source www.howstuffworks.com
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Power Supply cont'd
According to PC Power Cooling, Inc., some power
consumption values (in watts) for common items
ina personal computer are
AGP card 20 to 30 W PCI card 5 W floppy
disk drive 5 W network interface card 4 W
50x CD-ROM drive 10 to 25 W RAM 10 W
per 128 MB 5200 RPM IDE hard disk drive 5 to
11W 7200 RPM IDE hard disk drive 5 to 15W
Motherboard (without CPU or RAM) 20 to 30W 550
MHz Pentium III 30W 733 MHz Pentium III
23.5W 300 MHz Celeron 18W 600 MHz Athlon
45W
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Input/Output Processing

• 1. Programmed I/O
• The CPU executes a sequence of instructions,
  being in direct control of the I/O operations
  (sensing device status, read/write commands,
  etc.).
• When the CPU issues a command to the I/O
  module, it must wait until the I/O operation
  is complete.
• A lot of waisted time, because the CPU is much
  faster then devices.

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Input/Output Processing

• 2. Interrupt-driven I/O
• IRQ Interrupt Request
• After issuing an I/O command, the CPU has not to
  wait until the operation has finished instead
  of waiting, the CPU continues with other
  useful work.
• When the I/O operation has been completed, the
  I/O module issues an interrupt signal on the
  bus.
• After receiving the interrupt, the CPU moves the
  data to/from memory, and issues a new command
  if more data has to be read/written.

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Input/Output Processing

• 2. Interrupt-driven I/O cont'd
• Advantage over programmed I/O
• Instead of waiting the operation to be
  finished, the CPU can do some useful work.
• Still a problem
• If large amounts of data have to be moved, this
  technique is still not efficient, because the
  CPU has to take care of each data unit
  separately, to move it to/from memory.
• Handling the interrupt also takes some time.

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Input/Output Processing

• 3. Direct Memory Access (DMA)
• An additional module on the system bus, the DMA
  module (controller), takes care of the I/O
  transfer for the whole sequence of data.
• The CPU issues a command to the DMA module and
  transfers to it all the needed information.
• The DMA module performs all the operations it
  transfers all the data between I/O module and
  memory without going through the CPU.
• When the DMA module has finished, it issues an
  interrupt to the CPU.

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Device Manager MS Windows 2000
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References

• http//www.pctechguide.com
• http//www.howstuffworks.com
• http//www.zive.cz
• White, R. How computers work. Que, Indianapolis
  1999.
• Vrátil, Z. Postavte si PC. BEN, Praha 1999.
• Horák, J. Ucebnice hardware. Computer Press,
  Praha 1998.
• Precht, M. Meier, N. Kleinlein, J.
  EDV-Grundwissen Eine Einführung in Theorie und
  Praxis der modernen EDV. Addison-Wesley, 1996.
• ????????????, ?. ???????, ?. ??????????
  ???????? ??. ???, ?????-????????? 1999.
• ????????????, ?. ??????????? ?????????
  ??????????, ?????, ????????????. ?????,
  ?????-????????? 2000.