i/o decives cpu

of 20Chapter 10

GOHEL VISHAL. H

LECTURER OF COMPUTER DEPT.

GOVERNMENT POLYTECHNIC BHUJ

9638893297

I/O Ports and Devices

Chapter 10

of 20Chapter 10

Objectives Introduce ports Identify the different ports Work with the IEEE 1394 bus Configure IRQ Troubleshoot ports

of 20Chapter 10

Ports and show Introduction from CBT

Entry and exit point for data from the system

Connects the system and a device using a connecting cable

Located at the back or the front side of the system case

Ports have different shapes and sizes and you can not insert a plug in the wrong port

You can just unplug a device that is not used and plug in another device in that port

of 20Chapter 10

Port Symbols

Identifies the type of the port

Symbol PortSerial / COMParallelUSBIEEE 1394 / FirewirePS/2 – KeyboardPS/2 – MouseLine InLine OutMicrophoneJoystick

Bluetooth

of 20Chapter 10

Types of Ports

Types of Ports

Serial Parallel DIN5 PS/2 Infrared Bluetooth USB Firewire

of 20Chapter 10

Types of Ports

of 20Chapter 10

Serial Port and show through CBT

Sends and receives one bit of data at a time Known as the Communication or COM port Has 9 or 25 pins Connect devices such as the mouse, plotters and modems Transmitting device sends a start bit then actual data byte

followed by a stop bit Maximum cable length is 50 feet If you need more serial ports, you can install multi I/O

card

of 20Chapter 10

Parallel Port – I

Transmits eight bits of data at a time Has 25 pins Connects devices such as printers, scanners, external hard

drive and tape drive You can get more parallel ports by installing an expansion

card LPT1 uses IRQ7 and LPT2 uses IRQ5

of 20Chapter 10

IEEE 1284

Compatibility Mode – used for directing data from computer to peripheral (output only)

Nibble Mode – 4 bit (Input only) Byte Mode – uses software drivers same as nibble

mode (8 bit) Enhanced Parallel Port Mode (EPP) – it is

hardware driven and bi-directional, high speed parallel port interface

Enhanced Capability Port Mode (ECP) – same as EPP uses DMA

of 20Chapter 10

Parallel Port – II Different types of parallel ports are:

• Bidirectional – Uses byte and compatible mode for data transmission

• Standard Parallel Port (SPP) - Uses nibble and compatible mode for data transmission

• Enhanced Parallel Port (EPP) - Provides data transfer speed of 500 Kb to 2 Mb of data per second. It is built into super I/O chip or south bridge chip on motherboard

• Enhanced Capabilities Port (ECP) - Provides increased data communication speed to connect printer or scanner and supports DMA

of 20Chapter 10

DIN 5

Used to connect the keyboard to the system Known as the AT port Uses 5 pins for connecting the device

of 20Chapter 10

Pin Diagram of DIN5

AT keyboard connector (DIN5)

Connector Pin # Purpose

Pin 1 KBDCLK (clock)

Pin 2 KBDAT (data)

Pin 3 KBRST (reset, not used)

Pin 4 GND

Pin 5 VCC (+5V)

of 20Chapter 10

PS/2 (Personal System/2)

Used to connect the keyboard and the mouse Available in a color that matches the color of the device

plug Uses 6 pins to connect the device

Mouse PortKeyboard Port

of 20Chapter 10

Pin Diagram of PS/2

PS/2 keyboard connector (MINI-DIN6)

Connector Pin # Purpose

Pin 1 KBDAT (data)

Pin 2 not used

Pin 3 GND

Pin 4 VCC (+5V)

Pin 5 KBDCLK (clock)

Pin 6 not used

of 20Chapter 10

Universal Serial Bus (USB) Connects upto 127 devices to a single port Supplies power to the device Plug-and-play support Maximum cable length is 30m thus you can connect 5

hubs to the USB Has two different connections: connection A and

connection B USB 1.0 – 1.5 Mbps, USB 1.1 – 12 Mbps and USB 2.0 –

480 Mbps

of 20Chapter 10

USB Pin Diagram & Configuration

of 20Chapter 10

Infrared Ports

Communicate with the system without using wires Devices send out infrared signals that enter the system

through this port

Infrared Port

of 20Chapter 10

Bluetooth Port

Allows wireless communication between devices within a ranged distance

Uses 2.45 GHz frequency range for data communication A Bluetooth adapter required for the computer and a

Bluetooth compatible device to communicate Speed is 1 or 2 Mbps depending on the version

of 20Chapter 10

IEEE 1394 Bus Enables fast and high serial data transfer rate of upto 400

Mb per second Connects and supplies power to the connected devices

such as printer, scanner, web camera and generally used for transferring audio and video data from a camera to the system

Known as FireWire by Apple and iLink by Sony

of 20Chapter 10

S-Video Port

Short for Super-Video, a technology for transmitting video signals over a cable by dividing the video information into two separate signals: one for color (chrominance), and the other for brightness (luminance). When sent to a television, this produces sharper images than composite video, where the video information is transmitted as a single signal over one wire. This is because televisions are designed to display separate Luminance (Y) and Chrominance (C) signals. (The terms Y/C video and S-Video are the same.)

of 20Chapter 10

DVI Monitor Port

Short for Digital Visual Interface, in this case data is transmitted using the transition minimized differential signaling (TMDS) protocol, providing a digital signal from the PC's graphics subsystem to the display. The standard specifies a single plug and connector that encompass both the new digital and legacy VGA interfaces, as well as a digital-only plug connector. DVI handles bandwidths in excess of 160 MHz and thus supports UXGA and HDTV with a single set of links.

of 20Chapter 10

eSATA

Benefits of eSATA:• Up to 6 times faster than

existing external storage solutions: USB 2.0, & 1394

• Robust and user friendly external connection

• High performance, cost effective expansion storage

• Up to 2 meter shielded cables and connectors

• Applications: External Direct Attached Storage for notebooks, desktop, consumer electronics and entry servers.

of 20Chapter 10

Interrupt Request (IRQ) - I

Used by devices to communicate with the microprocessor

IRQNumber

Typical Use

0 System timer

1 Keyboard

2 Interrupt for IRQs 8-15

3 Second serial port (COM2)

4 First serial port (COM1)

5 Sound card

of 20Chapter 10

Interrupt Request (IRQ) - II6 Floppy disk controller

7 First parallel port. Used by the printer or any device using the parallel port.

8 Real-time clock

9 Open interrupt

10 Open interrupt

11 Open interrupt

12 PS/2 mouse / Network Card

13 Floating point unit/coprocessor. Only used for internal signaling.

14 Primary IDE channel

15 Secondary IDE channel

of 20Chapter 10

Show Configuring IRQ from CBT and show it practically

of 20Chapter 10

6 Channel Sound Card

A new version sound card is having 6 channels, which support multi speaker output. Can be easily installed on available PCI slot through PCI interface. Different manufacturers have different features for 6 channel sound card. Some of them support the features such as Direct sound 3D and DSL based Wavetable music synthesizer and 3D positional audio. It also contains a game port which supports 3D surround effect in games.

of 20Chapter 10

Wireless LAN USB Adapter

Connects computer to wireless LAN By using this adapter desktop, notebook and laptop users

can connect to a standard mobile network Plugged to computer through a USB port Data Transfer Rate is 54 Mbps

of 20Chapter 10

Troubleshooting and show how to resolve IRQ conflict practically

While using the device, errors may occur if there is a problem with the I/O port

Different types of problems related with IO port:• Device not working properly• IRQ conflicts

of 20Chapter 10

Serial or Parallel Cable Testing

Cable tester is used to verify the connections of the cables connected to the computer. It is an electronic device, which is used to check the connections in the cable. Consists of a current source, voltmeter and a switching matrix. All the contact points in the cable are connected to a source of current and a voltmeter using a switching matrix.

of 20Chapter 10

Summary – I

A port is used to connect the system and a device together, using a connecting cable.

The ports have different shapes and sizes that prevent you from connecting a device to the wrong port.

A serial port sends and receives one bit of data at a time. The parallel port transmits eight bits of data at a time. The PS/2 port is used to connect the keyboard and mouse to

the system. The USB port connects and also supplies power to the device.

of 20Chapter 10

Summary – II

Infrared ports enable wireless communication between the device and the system.

IEEE 1394 enables fast and high speed data transfer between the system and the connected devices.

Devices use the IRQ lines to communicate with the microprocessor.

IRQ conflicts occur when two hardware devices use the same IRQ line.

i/o decives cpu

Career