Study Lab for Chapter 8

I/O ports and devices cover a lot of territory, so it's time to hit the books! Use the following sections to get ready for this topic. Use the "Key Terms and Definitions" section of the lab to review terms used in this chapter. Try the "Practice Test" to check your comprehension of the chapter. Tackle the "Lab Exercises" to apply your knowledge.

Key Terms and Definitions

5-pin DIN

Original IBM PC/AT keyboard connector. Electronically identical to 6-pin mini-DIN connector.

6-pin mini-DIN

Also called the PS/2 keyboard connector; adapters can convert between 6-pin and 5-pin keyboards and connectors.

56K modem

Common term for any modem that can download at speeds above 33.6Kbps. Includes X2, K56flex, V.90, and V.92 standards.

AT commands

Used to control a modem or display its configuration; named such because all commands start with AT (attention) .

beta

1394b port that connects only to other 1394b devices.

bilingual

1394b port that can connect to 1394a or 1394b devices.

bus mouse

Obsolete mouse connector using an 8-pin mini-DIN round connector. Used a separate add-on card or port integrated into some graphics cards.

bus- powered hub

A USB generic hub that uses the upstream USB hub for power. A bus-powered hub provides no more than 100mA of power to each device connected to it.

Centronics

A port style that uses an edge connector. Parallel printers use a 36-pin version, whereas some versions of SCSI use a 50-pin version. Also called the IEEE-1284-B connector.

COM

Short for Communications port; another name for the serial port.

COM 1

First serial port. Default resource usage: IRQ 4 and 3F8-3FFh I/O port address.

COM 2

Second serial port. Default resource usage: IRQ 3 and 2F8-2FFh I/O port address.

COM 3

Third serial port. Default resource usage: IRQ 4 and 3E8-3EFh I/O port address.

COM 4

Fourth serial port. Default resource usage: IRQ 3 and 2E8-2EFh I/O port address.

Config.sys

A text-based configuration file used by MS-DOS and Windows 9x. Windows NT/2000/XP use Config.NT to perform similar functions.

daisy-chaining

Attaching multiple devices to a single port. Parallel ports have a limited capability for this, but USB hubs and IEEE-1394 devices do a much better job.

DB-9M

Newer D-shaped 9-pin male serial port. Can be adapted to use 25-pin cables.

DB-25F

A 25-pin D-shaped connector with holes; used for parallel ports on PCs and most parallel devices other than printers. Also called the IEEE-1284-A connector.

DB-25M

Original D-shaped 25-pin male serial port. Can be adapted to use 9-pin cables.

dongle

Proprietary cable that connects to a PC Card to enable it to work with standard cables.

ECP (Enhanced Capabilities Port)

Used by daisy-chained parallel devices, it uses an IRQ, I/O port address, and a DMA channel.

EPP (Enhanced Parallel Port)

Used by most recent parallel printers, EPP uses an IRQ and I/O port address.

EPP/ECP

Supports both modes and uses the same resources as ECP mode.

external modem

Modem that plugs into a serial or USB port.

FIFO (first in, first out)

A type of data buffer used on 16550 and newer UART chips to enable multitasking without loss of serial data under Windows.

FireWire

Apple's term for IEEE-1394 ports and devices. FireWire 400 is a recent term for IEEE-1394a; FireWire 800 is the same as IEEE-1394b. When FireWire is used without numbers , it usually means IEEE-1394a.

flow control

Various methods such as Xon/Xoff or CTS/RTS used to control data flow between modems.

FM synthesis

A method of simulating MIDI instrument sounds.

full-speed USB

USB 1.1 devices running at 12Mbps.

game port

15-pin port used for analog joysticks and game controllers. Not found on some recent sound cards or integrated audio systems because USB game controllers are replacing game-port based models.

generic hub

A USB hub connected to a root hub or another generic hub.

header cable

A cable running from the motherboard or add-on card that has the I/O port connector. Used mostly with Baby-AT motherboards or multi-I/O cards.

Hi-Speed USB

Another name for USB 2.0.

hot-swap

Ability to change USB and IEEE-1394 devices without shutting down the system. Introduced with Windows 98 Second Edition. PC Cards can also be hot-swapped in these versions of Windows and older versions as well.

hybrid mouse

A mouse or other pointing device that can connect to more than one type of port.

i . LINK

Sony's implementation of IEEE-1394a; it uses a four-wire cable at both ends.

IEEE-1284

Official standard for parallel ports. An IEEE-1284compliant parallel cable supports all parallel port modes, including EPP, ECP, and EPP/ECP.

IEEE-1284-C

Small version of the IEEE-1284-B connector used on some laser printers.

IEEE-1394

A family of high-speed serial technology ports and devices. Similar in some ways to USB, IEEE-1394 devices can transfer data without a computer.

initialization string

Series of AT& commands used to configure the modem before dialing.

integrated audio

Sound card features built into the motherboard.

internal modem

Modem built into an add-on card (PCI or ISA).

IRQ conflict

Conflict between two ISA devices or an ISA and PCI device trying to use the same IRQ. Causes device failure or system crash until conflict is resolved.

K56flex

Proprietary 56Kbps modem standard developed by Rockwell; now replaced by V.90.

legacy port

General term for serial, parallel, and PS/2 mouse and keyboard ports.

legacy-free

A system without serial or parallel ports. Often lacks PS/2 mouse and keyboard ports.

line printer

Another name for a parallel printer; LPT is the abbreviated form also used to refer to a parallel port.

loopback plug

A plug that has the transmit and receive lines connected to each other. Used to test serial and parallel ports.

low-speed USB

USB 1.1 devices running at 1.5Mbps such as a mouse or a keyboard.

LPT

Parallel port.

LPT1

First parallel port; has defaults of 378-37Fh or 3BC-37Fh and IRQ 7 (in EPP or ECP modes); ECP mode also uses DMA 3.

LPT2

Second parallel port; has defaults of 278-27Fh or 378-37Fh and IRQ 5 (in EPP or ECP modes); ECP mode also uses DMA 3.

MIDI (Musical Instrument Digital Interface)

A method of playing a musical score through a sound card.

mini-PCI

An expansion slot type found in many recent notebook computers, which is used for modem, 10/100 Ethernet, and wireless Ethernet ports. Mini-PCI devices are customized for the notebook computers they are used with, and are currently not sold at retail.

mixer

The volume, balance, and other controls used by audio hardware. Open the Speaker icon in the Windows system tray or open the Sounds icon in Control Panel to adjust settings.

modem

Device that converts digital-to-analog signals or analog-to-digital signals; transmits or receives analog signals through telephone lines. Also called analog modem or dial-up modem .

multi - I/O card

Card that contains two or more different types of I/O ports. Typically includes one or more parallel and one or more serial ports, but other combinations are possible.

optical mouse

A mouse that uses a miniature camera to track mouse motion instead of a ball. Some very old mouse devices used a metal plate with a grid, but current models can work on almost any non-mirrored surface.

parallel port

Also called Line Printer or LPT port , it's used for parallel printers and other high-speed external devices. Uses a DB-25F connector on the computer and a Centronics 36-pin edge connector on printers. Other devices also use a DB-25F connector.

parity

Error-checking method; some remote computers use even or odd parity, whereas the Internet uses no parity checking.

PC Card

Credit-card sized storage, memory, or I/O devices for notebook computers that use the standards established by PCMCIA.

peripheral

An external device not required for basic computer use but added to enable a computer to perform a particular task, such as printing or communications with another computer.

PnP (Plug and Play)

A Windows 9x/Me/2000/XP feature that configures PCI and plug-and-play-compliant ISA cards and devices.

PS/2 mode or bidirectional mode

Uses eight wires for both input and output, and only I/O port addressing.

ripping

Converting CD audio tracks into compressed digital audio files such as MP3 or WMA.

RJ-11

Four-wire connector telephone jack using unshielded twisted-pair (UTP) cabling.

RJ-45

Eight-wire connector similar to RJ-11, but larger. Used for Ethernet networks.

root hub

Name for USB hub built into motherboard or I/O card. Each root hub handles two USB ports.

RS-232

Recommended Standard-232; the formal name for the serial (COM) port standard.

S/PDIF

Sony/Philips Digital Interface; a digital sound interface standard. Might use wired or optical-cable connectors.

S-registers

Modem registers used to store or adjust timing and other technical details.

self-powered hub

A USB hub that plugs into an AC power source. Can be used with devices that require more power than a bus-powered hub can provide. A self-powered hub provides 500mA of power for each USB port.

serial port

RS-232 or COM port, a 9-pin or 25-pin male port used for slow-speed devices.

Series A

Flat USB connector used to connect USB devices with fixed cables to a USB root hub or generic hub.

Series B

Notched-square USB connector found on external devices with USB ports. A typical USB cable has a Series A connector on one end and a Series B connector on the other end.

SET

A command-line command used to configure settings for a particular program.

SET BLASTER

This command sets up the software used by Sound Blaster and compatible sound cards in DOS.

soft modem

Another term for a Winmodem.

Sound Blaster

A line of sound cards from Creative Labs that have become a de facto industry standard.

standard mode

Original parallel port mode, uses only I/O port addressing.

stop bit

Bit used to indicate a byte (character) has been sent.

switchbox

A mechanical or electronic device with multiple serial or parallel ports. Two types exist: Share one port with multiple devices, or a single device can be shared by multiple computers.

touchpad

Mouse alternative that uses a touch-sensitive pad to detect movement. Pressing the surface with the finger can also be used for double-clicking as an alternative to using the buttons provided.

trackball

Mouse alternative that uses a large ball on top of the device; the ball is moved with the thumb or other fingers.

UART (Universal Asynchronous Receive Transmit) chip

The heart of a hardware serial port. Frequently emulated on recent systems. UART types include 8250, 16450, 16550, 16550A, 16550AFM, 16650, 16750, 16850, and 16950.

Universal Serial Bus ( USB )

Flexible replacement for serial, parallel, and PS/2 mouse and keyboard ports.

USB 1.1

12Mbps version of Universal Serial Bus port.

USB 2.0

480Mbps version of Universal Serial Bus port, backward compatible with USB 1.1. Also known as Hi-Speed USB.

USB Legacy mode

BIOS setting that enables USB keyboards (and sometimes mouse devices) to work outside the Windows GUI (such as at a command prompt or in the BIOS setup program).

V.90

International standard; 56Kbps modem is the standard.

V.92

Improved version of V.90; adds support for call waiting and faster uploading.

wavetable

A method of playing MIDI scores using digitized samples of actual musical instruments.

Winmodem

A modem that depends upon Windows and the processor to perform the task of converting signals; originally developed by U.S. Robotics.

word length

Number of bits in each character (word) sent; some remote computers use 7-bit, whereas the Internet uses 8-bit.

X2

Proprietary 56Kbps modem standard developed by U.S. Robotics; now replaced by V.90.

Practice Test

1:	A client needs to daisy-chain a parallel printer and a scanner. Which combination of BIOS setting and parallel cable type will produce the best results? (Choose one) EPP and a bidirectional cable ECP and a bidirectional cable EPP/ECP and an IEEE-1284 cable PS/2-bidirectional and an IEEE-1284 cable
2:	You are trying to install a PCI sound card that must work in Sound Blaster compatibility mode into a system with two parallel ports in EPP mode. Which of the following hardware resources is most likely to conflict? (Choose one) IRQ DMA IRQ and DMA I/O port address
3:	A client asks you to connect a serial device to a computer. However, the serial device has a 25-pin cable and the serial port on the computer is a 9-pin type. Which of the following steps should you take to complete the job? (Choose one) Install a serial port or multi-I/O card with a 25-pin serial port. Replace the serial device with a similar model using a 9-pin cable. Obtain the pinouts of both devices and build a custom cable. Install a 25-pin to 9-pin serial adapter.
4:	A PC has two serial ports, COM 1 and COM 2, both using default settings. COM 1 is used by a mouse, while COM 2 is not in use. If an internal modem is installed, which of the following settings can be used? (Choose all that apply) Install the modem as COM 3 using default settings. Install the modem as COM 4 using default settings. Install the modem as COM 2. Disable COM 2 and install the modem as COM 2.
5:	A client wants to connect four USB 1.1 devices with two USB 1.1 and two USB 2.0 ports. Which connection strategy will produce the best performance now and room to add more devices later? (Choose one) Connect all USB 1.1 devices to a single USB 1.1 port with a hub. Connect two USB 1.1 devices to each port with hubs. Connect all USB 1.1 devices to a USB 2.0 port with a USB 2.0 hub. Connect one USB 1.1 device to each USB port.
6:	You need to connect the following devices to a USB hub: a device using 100mA, a device using 48mA, a device using 500mA, and a device using 498mA. You have a self-powered hub and a bus-powered hub. Which of the following statements best reflects your options? (Choose one) If you connect only the device using 500mA or 498mA to the bus-powered hub, it will work. If you connect all devices to the bus-powered hub, none of them will work. If you connect all devices to the self-powered hub, all of them will work. You need to count the ports on each hub to determine the available power before you can choose which hub to use.
7:	You need to install a modem in a computer running Windows XP that might also be used to run Linux in the near future. Which modem technologies are most likely to work both with Windows XP and with Linux? (Choose one) HSP only DSP only DSP and UART HSP, DSP, and UART
8:	Your client has been trying to adjust the modem's configuration, but has rendered the modem unable to work. Which of the following commands can be used to reset the modem to its original condition? (Choose one) ATDT ATP ATH ATZ0
9:	Your client wants to install a wireless keyboard that uses a USB-based transceiver in place of the conventional PS/2 keyboard. Which of the following BIOS settings should be enabled before switching keyboards? (Choose one) Enable USB port Enable USB 2.0 mode Enable USB Legacy mode Disable USB Legacy mode
10:	Which of the following mouse devices can be used with traditional and legacy-free systems, including systems running Windows 95 and Windows XP? (Choose one) Serial mouse with PS/2 adapter PS/2 mouse USB mouse USB mouse with PS/2 adapter
11:	Your client complains that the mouse pointer is too hard to see. Which of the following changes will satisfy the client? (Choose one) Replace the mouse. Install updated mouse software. Select a new mouse pointer. Adjust double-click speed.
12:	Your client is generally satisfied with the integrated audio on the system, but can't play music CDs. Which of the following is most likely to solve the problem? (Choose one) Enable music CD playback in the system BIOS setup. Replace the integrated audio with a sound card. Connect the optical drive to the motherboard's analog audio jack. Connect the speakers to the headset jack on the front of the drive.
13:	Your client wants to connect a fourth IEEE-1394a device to a system that has only three 1394a ports. Which of the following is the best solution to this problem? (Choose one) Install another 1394a port. Purchase a 1394a hub. Daisy-chain the new device to one of the existing devices. Determine if the new device can be connected to a USB port instead.

Lab Exercises

Required equipment: working system, I/O card(s) to install (serial, parallel, IEEE-1394a, USB, and sound), ESD protection (wrist strap and antistatic mat), device that can plug into the I/O card you will install, drivers for I/O card, and device and tools to open system

I/O Port Detective

Objective : Determine what I/O ports are already installed and available.

1. Look at all sides of the system and record the I/O ports that you find:

   Serial

   Parallel

   USB

   IEEE-1394a

   Game port

2. Does the system have onboard audio? Y/N

3. Does the system have a sound card? Y/N

4. Start the system and enter the BIOS setup program.

   Are any serial ports disabled? Y/N

   Is the parallel port disabled? Y/N

   For what mode is the parallel port set?

   EPP, ECP, EPP/ECP, or other _______

   Change the setting for one of these ports (preferably one you're not using) and save the changes. Restart the system.

5. View the Windows Device Manager. Are any ports disabled or not working? Y/N

I/O Port Upgrades

1. Shut down the system and take ESD precautions as described in Chapter 12.

2. Open the system and examine the open expansion slots.

   List the total and available number of PCI slots.

   Any other slot types available? (List)

3. Install an add-on card and configure it as needed. If you are installing a sound card, repeat the first exercise and disable onboard sound if present.

4. Restart the system and complete the configuration process.

5. View the Windows Device Manager and determine if the new I/O port works and what its settings are.

6. Connect a device to the new I/O port and try it. Install any necessary drivers. Does the device work?

Answers to Practice Test

A1:	Answer C (EPP/ECP and an IEEE-1284 cable) is correct. This setting enables both the scanner and printer to use which mode (EPP or ECP) works best, whereas the IEEE-1284 cable enables both devices to send and receive all necessary data.
A2:	Answer A (IRQ) is correct. LPT 2 uses IRQ 5 by default, and the default IRQ used by a sound card in Sound Blaster mode is also IRQ 5.
A3:	Answer D (install a 25-pin to 9-pin serial adapter) is correct. 9-pin and 25-pin serial ports carry the same signals, just on different pins.
A4:	Answers B (install the modem as COM 4 using default settings) and D (disable COM 2 and install the modem as COM 2) are correct. Both COM 2 (unused here) and COM 4 use IRQ 3 by default, while COM 1 uses IRQ 4, avoiding a conflict between the ports.
A5:	Answer C (connect all USB 1.1 devices to a USB 2.0 port with a USB 2.0 hub) is the best answer. USB 2.0 ports can manage multiple USB 1.1 devices better than USB 1.1 ports do. This answer leaves a USB 2.0 port open for future use.
A6:	Answer C (if you connect all devices to the self-powered hub, all of them will work) is correct. The key here is to remember that a bus-powered hub provides only 100mA of power per port, no matter how many devices are plugged into it.
A7:	Answer C (DSP and UART) is correct. Modems that use a DSP (digital signal processor) are easier to update than UART-based modems, but have similar performance. HSP modems (soft modems) often can't work with non-Windows operating systems.
A8:	Answer D (ATZ0) will make you an instant hero! This command resets the modem to factory configuration 0.
A9:	Answer C (enable USB Legacy mode) is the right one. USB Legacy mode makes USB keyboards work in any situation. Otherwise, as soon as you exit the Windows GUI, your keyboard becomes a paperweight.
A10:	Answer D (USB mouse with PS/2 adapter) keeps you mousing along under any circumstances. Legacy-free systems dump the serial ports overboard, and often don't have PS/2 ports either.
A11:	Answer C (select a new mouse pointer) will do the trick. You can choose several sizes of mouse pointers and also try different shapes . Do it through the Mouse icon in Control Panel.
A12:	Answer C (connect the optical drive to the motherboard's analog audio jack) will bring out the DJ in your client. Some recent media players for Windows convert the tracks into digital form through the ATA/IDE cable and then play them back, but using the analog audio jack enables older and newer systems to be used as stereos.
A13:	Answer C (daisy-chain the new device to one of the existing devices) is a winning solution. Most 1394a devices have a second pass-through port for daisy-chaining.