The document discusses different types of buses, interfaces, and cards used in computer systems. It provides examples of expansion buses like ISA and PCI that provide slots on the motherboard. Disk interfaces like ATA, IDE, and SCSI are covered that connect hard disks. External buses like parallel, serial, USB are described along with communication buses for connecting systems. Common cards like graphics cards with DVI/VGA ports and sound cards with audio jacks are detailed.

1. Computer Maintenance and Technical
Support
Chapter Seven
Bus and Cards
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2. Bus and Cards
Buses - a path through which data can be sent to the different parts
of the computer system.
• Two different parts of a Bus
– Address bus -transfers information about where the data should
go
– Data bus -transfers the actual data.
• Bus width is the size of the bus lines.
• It determines the number of bits that the computer
can transmit at one time (say, one clock cycle).
– eg: a 32-bit bus can transmit 32 bits at a time.
– the larger the bus width, the faster the transmission.
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3. Examples
• Expansion buses or “slots”
• Disk interfaces/Buses
• External buses
• Communications buses
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4. Expansion Buses
• These are “slots” on the motherboard
• Examples
– ISA – Industry Standard Architecture
– PCI – Personal Component Interconnect
– EISA – Extended ISA
– SIMM – Single Inline Memory Module
– DIMM – Dual Inline Memory Module
– MCA – Micro-Channel Architecture
– AGP – Accelerated Graphics Port
– VESA – Video Electronics Standards Association
– PCMCIA – Personal Computer Memory Card International
Association (not just memory!)
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5. 3 ISA
slots
5 PCI slots
Pentium
CPU
6 SIMM
slots
2 DIMM
slots
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6. Disk Interfaces
• Examples
– ATA – AT Attachment (named after IBM PC-AT)
– IDE – Integrated Drive Electronics (same as ATA)
– Enhanced IDE
• Encompasses several older standards (ST-506/ST-412, IDE, ESDI,
ATA-2, ATA-3, ATA-4)
– SCSI – Small Computer Systems Interface
– ESDI – Enhanced Small Device Interface (mid-80s,
obsolete)
– PCMCIA
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7. External Buses
• Examples
– Parallel – sometimes called LPT (“line printer”)
– Serial – typically RS232C (sometimes RS422)
– PS/2 – for keyboards and mice
– USB – Universal Serial Bus
– IrDA – Infrared Device Attachment
– FireWire – new, very high speed, developed by
IEEE
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8. Communications Buses
• For connecting systems to systems
• Parallel/LPT
– special purpose, e.g., using special software
(Laplink) to transfer data between systems
• Serial/RS232C
– To connect a system to a voice-grade modem
• Ethernet
– To connect a system to a high-speed network
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9. Cards
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1
2
4
5
1 Processor and fan
Graphics card handles it’s own processing making it
almost independent of the processor.
2 Board connector AGP or PCI-Express
3 Memory
Graphics card has it’s own memory. This makes it much
faster. Most new cards use DDR3 memory.
4 DVI connector Digital output is supplied through this port.
5 VGA connector Analogue output is provided through this port.
Graphics card
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10. Cards
Graphic card - screen images are made up of dots
called pixels (picture elements). The graphics card
must process each of these pixels to create the image.
The resolution of a screen is the number of pixels
being displayed. Typical resolutions include:
• 800 x 600 - 480,000 pixels
• 1024 x 768 - 786,432 pixels
• 1280 x 1024: - 1,310,720 pixels
• 1600 x 1200: - 1,920,000 pixels
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11. Cards
1
2
3
Sound card
1 PCI connector Connects the sound card to a PCI slot
2 MIDI socket
Musical Instrument Digital Interface port is used
to connect digital musical instruments to the
computer.
3 Audio jacks
These are used to connect microphones, speakers,
stereo systems etc to the computer.
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12. Cards
• allows computers join a network. Can be wired
or wireless. The standard used is called
Ethernet - covers wired and wireless
networks.
The wired standards include:
• Fast Ethernet - transmission speed of
100Mbps.
• Gigabyte Ethernet - transmission speed of
1000Mbps.
PCI PC card USB
Network card
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13. Cards
The wireless standards include:
• The B standard - introduced in 1999, it has
a transmission rate of 11Mbps and a range of
30 Metres.
• The G standard - introduced in 2003, it has
a transmission rate of 54Mbps and a range of
30 Metres.
• The N standard - introduced in 2006, it has
a transmission speed of 540Mbps and a
range of 50 metres.
PCI PC Card USB 13

14. Cards
Replaces floppy drives in new computers. They can
read media cards from most digital cameras:
• Microdrive:
• Smartmedia:
• SD memory card:
• Memory stick/Duo/Pro:
• xD picture card:
Card readers
Card reader drive
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15. Quiz
Name ______________ID ______
1. Write one example of Expansion Buses/slot?
Ans =SIMM,DIMM,PCMCIA,ISA,PCI,EISA…..
2. Write one example Disk interfaces ?
Ans =ATA,IDE,SCSI,ESDI,PCMCIA…..
3. Write one example External buses ?
Ans=PARALLEL,SERIAL PS/2,VGA,USB….
4. Write one example Communications buses?
Ans =….. ., using special software (Laplink)
5. Write two examples of Cards?
Ans=GRAPHIC CARD AND SOUND CARD
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