So far we have wrestled
with Memory, the CPU,
Bits and Bytes, Input and
Output.
Yep, Now it’s high time to put
some of this together. Where
else than the computer’s
MOTHERBOARD ?
CBP 2002
ITY 117 Digital Technologies
Computer Components
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ITY 117 Digital Technologies
I/O Devices sorted by bandwidth
Joystick
Keyboard
Mouse
TV Camera
CD Rom
IDE HDD
Audio
Scanner
VDU
10 B/s 100 B/s 1kB/s 10 kB/s 100 kB/s 1 MB/s 10 MB/s 100 MB/s
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ITY 117 Digital Technologies
Fast Components
Hard Disk
Memory
CPU
Video Card
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ITY 117 Digital Technologies
Slow Components
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Sorting Devices by Bandwidth
• Classify Devices by their bandwidth (speed in Bytes/sec)
• Connect devices within each class together
• Then Connect classes together
Incredibly Fast
This gives us the
structure of a PC
Motherboard
Fast
Slow
CBP 2002
ITY 117 Digital Technologies
Buses
Incredibly
Fast
The connection are
called Buses
Fast
Slow
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ITY 117 Digital Technologies
Buses – What are they ?
Coordinated means of moving
information around. Bandwidth?
PETEHOUND
Wires on pcb
CPU
Disk drive
1 0 1 1
Memory
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ITY 117 Digital Technologies
PCB Bus tracks near a Pentium 4
Physical bus –
load of tracks on
a PCB (printed
circuit board)
CBP 2002
ITY 117 Digital Technologies
Buses – They are :
•
•
•
•
Shared communication link
Single set of wires used to connect multiple subsystem
Designed speed (“Bandwidth”)
A Bus is also a fundamental tool for building complex systems
Poor
Good
CBP 2002
• It creates a communication bottleneck
• The maximum bus speed is largely limited by:
– The length of the bus
– The number of devices on the bus
• New devices can be added easily
• Peripherals can be moved between computer
systems that use the same bus standard
• A single set of wires is shared in multiple ways
ITY 117 Digital Technologies
A Grand Mother Board
Incredibly
Fast
Pentium
III
Very Fast
440
North
Bridge
Organizing components
by their speeds
Cache
Main
Memory
Graphics
PCI Bus
Fast
IDE
DIsk
USB
South
Bridge
KBd
SCSI
Graphics
Mouse
ISA Bus
Slow
Modem
CBP 2002
Printer
Sound
ITY 117 Digital Technologies
A Grand Mother Board Itox3
ISA Slots
PCI Slots
CPU Socket
North Bridge
South Bridge
simm
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ITY 117 Digital Technologies
Two Types of Bus
USB Universal Serial Bus
• Slow 1MByte / sec
• used for mice printer audio
• frame and packets – like network
Serial Bus
• PC’s mouse and keyboard
• used for mice printer audio
• frame and packets – like network
CBP 2002
ITY 117 Digital Technologies
PCI Bus
• Precursor was ISA - 8MHz 16 bit
• Original PCI 33 MHz 32 bit 100 MB/sec
• Now extended to 64 bit and 64 MHz
• Synchronous, multiplexed
• 5Volt or 3.3 Volt logic levels
• Plug and Play Support
• PCI-X 2.0 64 bit 533 MHz
ISA Slots
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ITY 117 Digital Technologies
PCI Slots (32 bit)
Connections to the Motherboard
PS-2 Kbd mouse
Printer / Parallel
Game
USB
Audio
Serial
Video
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ITY 117 Digital Technologies
A Modern Mother Intel D815
MCH
IOCH
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ITY 117 Digital Technologies
A Modern Mother’s Chipset
Incredibly
Fast
No Northbridge
No Southbridge
A New Grouping
Very Fast
Slow
Fast
Fast
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ITY 117 Digital Technologies
Slow
A Modern Mother Intel D815
Back Panel Connectors
Codec
PCI Bus
AGP
CPU Socket
MCH
IOCH
Battery
DIMM
HDD
FDD
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ITY 117 Digital Technologies
D815 Plan
Back Panel Connectors
Codec
CNR
PCI Bus
AGP
MCH
Battery
IOCH
DIMM
HDD
FDD
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CPU Socket
ITY 117 Digital Technologies
D815 CPU – Memory Control Hub
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D815 Input-Output Control Hub
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Glossary
• PCI
Peripheral Component Interconnect
• simm single inline mem module
• ISA
Industry Standard Association
• dimm dual inline memory module
• USB
Universal Serial Bus
•MCH
Memory Control Hub
• Codec Coder-Decoder (audio media)
• IOCH IO Control Hub
• AGP
Advanced Graphics Port
• IO
Input or Output
• HDD
Hard Disk Drive
• LAN
Local Area Network
• FDD
Floppy Disk Drive
• SIO
Serial Input Output
• SCSI Small Computer System Interface
• PIO
Parallel IO
• CPU
Central Processor Unit
• OTT
Over The Top
•PCB
Printed Circuit Board
• IDE
Integrated Drive Electronics
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Investigating Circuit Boards
Here’s some photographs which will help you recognize what a
printed circuit board’s function is.
Parallel Port Printer
Video Port
Ethernet (OLD)
USB
Serial Port
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PS/2 mouse,
Keyboard
BIOS ROM
Battery for CMOS
OLD Keyboard conn
Power Connector
Bleeper
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LED Display
ITY 117 Digital Technologies
Investigating Circuit Boards
Here’s some CHIP Identification Numbers that may help you
identify some Circuit Boards
• 80386 Intel CPU
• 8255 Input/Output Chip
• 80486 Intel CPU
• WD---- Disk controller chip
• 8051 Microcontroller
• 80282 ancient CPU
• 8086 Intel CPU (early)
• 8237 Disk input output
• 2732/64/128/256 EPROM
• 8254 Programmable Timer
• 68030/40 Motorola CPU
• 8041 Keyboard controller
• 8049 Keyboard controller
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Microcontrollers
• Chips containing CPU
RAM IO Ports, Timers.
• Used in Car Engine
Management Systems
• Used in Alarm Systems
• Also in Coffee Machines
• Intel 8051-family
• This one in a Furbie
CBP 2002
ITY 117 Digital Technologies
CBP 2002
ITY 117 Digital Technologies