THE KEYBOARD BASIC FUNCTION

The keyboard is one of the most important components of a personal computer because it is the primary device through which a person communicates with a computer. The keyboard attaches to the system with a coiled cable. On many machines this cable stretches about six feet, which permits the keyboard to be positioned wherever it will be the most functional or comfortable, even on a person’s lap. Many manufacturers build two forms of feedback into keyboards: tactile and audio. Tactile feedback occurs when you press a key and feel the slight pressure that builds up and then releases, indicating that the keystroke has registered and the character or command has been sent to the computer. As this happens, the audio feedback, a soft click like the click of a typewriter key, is heard. This feedback helps make the keyboard easier to use when a person is reading from notes while entering data.

IBM and many IBM compatibles feature keyboards with 83 keys that access 256 characters. You don’t always see every character displayed on the keys themselves, but they are there, stored in 11w l.OM. For example, if you looked at the letter ‘I” on the keyboard, you would only see it displayed in uppercase. It will also lowercase, of course, but it can also display the symbol “L,” which denotes England’s currency.

The keyboard as seen in Figure 33 has a standard typewriter layout in the middle, a numeric keypad to the right (which doubles as a set of cursor-control keys), and 10 special function keys to the left

  

 FIGURE 33. Standard Keyboard Layout.

One important point: There is no way a person can damage the computer by using the wrong keys: As discussed in Chapter One, many people are afraid that if they touch the wrong key something terrible will happen. This simply isn’t so. A person may not get the results he or she was expecting, but striking a wrong key will not hurt the system itself.

Function keys

There are usually 10 special function keys (see Figure 34), which are found either on the left-hand side of the keyboard, or across the top of it. These have programmable functions that change with the software program. For example, in a word processing package they might govern how a page of text appears on a screen depending on the software package, these can have different uses.

 

Note:  Not all keys will be used with all programs. Check the reference manuals provided with your software to be sure.

Important Usage Keys:

Enter Key                         Tells the computer to process the      

                                                                                                                      Information YOU have been working on

                                                                   ESCAPE                                 Performs different functions, but

                                                                                                              Usually allows you to exit a program.

                                                           TAB                                  Moves cursor eight spaces at once   

                                       CONTROL                       Used in connection with other 

                                                                                                                keys to modify their           

                                                ALTERNATE                         Used with other keys.     

                                                SHIFT                  Enters upper case letters and 

                                                                                                   top ‘symbol’ of dual character keys.  

                                     BACK SPACE          Moves cursor back one space, and                  

                                                                                                erases each character it passes.

                                                 CAPS LOCK                Locks in upper case characters.

                      SPACE BAR                 Locks in upper case characters

 

The numeric keys are really dual purpose keys that allow you to either enter numeric data or to perform special uses. The “Numlock” key serves as a ‘toggle switch)” that allows you to change the keypads function.

Note: not all keys will be used with all programs. Check the reference materials provided with your software to be sure.

(Known as formatting), or the movement of text within a document. In another program, they can perform a completely different set of comman4s. In BASIC they can compress commands that are 15 characters long into one kçy. Instructions for the function keys are usually found at the front of the software programs manual. Many products also include templates that fit over these keys for easy reference.

Numeric keypad

The numeric, calculator-like keypad on the right side of the keyboard performs two functions:

1. It can serve as a calculator.

2. It controls the movements of, the cursor.

These functions are controlled by the “num lock” key, which acts like a toggle switch. Press it once and the numeric keypad can be used to enter numbers. Press it again and the same set keys control the cursor. The cursor can be moved up, down, left, right, to the top of the screen, or to the end of a file. Two cursor-control keys, labeled “Pg Up” and “Pg Dn,” work with word processing and other programs to view previous succeeding sections of a document. Other keys provide the ability In delete or inwii characters into an existing body of text.

Control key combinations

‘The control key is used in combination with other keys to perform

a variety of functions:

Combination Keys                                                                             Results

Ctrl + Scroll lock                                                           Causes a break in the program.

Ctrl + Num Lock                                                           Causes a pause in the program.

Ctrl + Alt + Del                                                               Causes a system reset (a warm boot).

Ctrl + left arrow                                                            Causes the cursor to move back one word.

Ctrl + right arrow                                                          Causes the cursor to move forward one word. 

Ctrl + PrtS                                                                      Sends output to both the screen and printer                           

                                                                                        Simultaneously. This is called a print echo, or a screen

                                                                                        dump. This is a good way of making a copy of one 

                                                                                         Particular screen without printing anything e1se.

Ctrl + End                                                                      Erases the screen beginning with the current cursor

                                                                                       Position to the end of the line.

Ctrl + PgDn                                                                 Erases the screen from the current cursor position to the

                                                                                                 End of the screen.

Ctrl + Home                                                                  Clears (blanks) the screen and sends the cursor to the

                                                                                               home position.

 

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SOME BASIC ESSENTIALS FOR COMPUTERS

              There is no better place to begin, than the beginning

This chapter is designed to accomplish two things:

1. Provide a basic understanding of how to work with a personal computer.

2. Serve .is guidelines for materials to include in personal computer training programs.

The information in this chapter assumes no prior knowledge of or experience with a personal computer. Anyone who has a comfortable working relationship with a personal computer may wish to skim over this section to get ideas of how to structure an introductory training course. For others starting from scratch, however, the chapter will focus on building a working knowledge of:

The keyboard

The operating system

Working with diskettes

Security and backups

GETTING STARTED

As noted earlier, the two most common types of personal computers that will be encountered in most organizations are machines containing two diskette drives, and those with one diskette drive and a hard disk.

Diskette drives refer to the number of slots on the microprocessor for inserting diskettes. Two-drive systems have one slot for the program diskette and one for working on and storing the results (see Figure 30).

Since hard disks offer the storage equivalent of 30 diskettes, they require only one diskette drive for entering information (see Figure 31), although they may be configured with two drives for more sophisticated applications. In either case, the loading process is the same. The diskette drive(s) has an opening through which diskettes are inserted into the computer. Each opening has a device similar to a door that can be opened and closed using what is called a lift load lever. Once a diskette is inserted, the door is closed behind it by pushing the load lever down. While the system reads your program, a small red light on the front of your disk drive will come on. Do not open the drive door while this light is on. Doing so may permanently damage the program, and under some circumstances the system unit itself.

 

 

 

 

FIGURE 31. Proper way of loading a diskette. Courtesy of International Business Machines.

To make things more comfortable, it is possible to make minor adjustments to the height of the keyboard and the brightness and contrast of the display monitor. If the display monitor is near a source of bright light, such as a window, or has a high degree of glare, an anti glare screen might be appropriate.

Depending on the model, most keyboards have two to three possible positions. These range from, flat to a five-degree to 15 degree angle. To adjust the height, pick up the keyboard and, make the  necessary adjustment using the knobs at each end.

Brightness and contrast can be adjusted using the control knobs generally found on the front of the monitor. On systems that share multiple users, this will probably have to be done every time a person sits down to work. Everything a computer does is governed by operating sys tern, which is a software program that manages many of the computer’s basic functions. It acts as an intermediary between hardware and software and performs such tasks as controlling the input output devices, assigning spaces in memory to programs and data, and controlling how the system processes information. -

For IBM and IBM-compatible machines the operating system is called DOS (Disk Operating System), MS-DOS, or PC-DOS. They all perform the same basic functions.

The operating system must be present whenever a system is on in order for anything to be accomplished. In addition, it must be copied to all software before that software can be installed or used. Most software is generic in nature and written to be run on more than one brand of machine. Copying the operating system onto a software program allows it to become compatible with a particular system. Instructions accompany most software programs.

Booting is the process of actually loading DOS into a system. Booting clears the memory, loads the operating system, and gets the computer ready to process its work. If this is done when a machine is first turned on, it is called a cold boot. If the operating system is loaded after a system is already up and running, it is called a warm boot.

To perform a cold boot, simply put a copy of DOS or its equivalent in Drive A, and turn the computer on. The on—off switch that controls the system unit or microprocessor is located at the rear of the unit. On IBM machines, the switch will always be on the right-hand side (see Figure 32).

This is the recommended way to activate an entire system:

First, turn on the printer

Second, turn on the monitor

Third, turn on the CPU

Follow this sequence because one of the first things a system unit does is to check what is connected to it, and whether or not they are working properly. Turning the system on as described

 

 

FIGURE 32. Locations of on/off switch on IBM system unit. Courtesy of International Business Machines.

is the most effective way to accomplish this. If a unit is connected to multisocket electrical power strip or surge suppressors check to see that it is turned on as well. Many people control the power to all their system components through such devices, using them to turn everything on simultaneously.

When the power is switched on, the first sound heard will be the motor humming as the computer checks to see how much memory it has  take from 3 to 90 seconds, depending on how much memory has been installed. Memory will be counted in units   which can be seen blinking by at the top left—hand corner of a monitor.

When the memory check is completed, the computer will emit a short beep, and then display the following message:

Current date is 01-01-1980

Enter new date:

At this point, a person may simply hit the “enter” key, or may provide the current date. If he or she is working with file materials, or materials that may require future reference, a date should be entered. To enter a date, the computer must be given the month, 1-12, day, 1-31, and year, 80-99. A correct entry might be: 10-14-1986.

The operating system will then ask for the time. Again, the choice is to simply hit “enter,” or supply the current time. Since a 24-hour clock is used, any time past noon should carry one of the following values:

1:00 = 1300 hr

2:00 = 1400 hr

7:00 = 1900 hr

8:00 = 2000 hr

3:00 = 1500 hr 9:00 = 2100 hr

4:00 1600 hr

5:00 1700 hr

6:00 = 1800 hr

10:00 = 2200 hr

11:00 = 2300 hr

12:00 = 2400 hr

The time is expressed in hours: minutes: seconds: and hundredths. Colons (:) must be used between• hours, minutes, and seconds. Any value that is omitted will be assumed to be a zero. For example, if it is 2:30 in the afternoon, you would enter 14:30 hrs. And the system would record 14:30:00.

To perform a warm boot, the system must be restarted by using the “Cntrl,”“Alt,” and “Del” keys simultaneously. The operating system disk should be in drive A, unless the system has a hard disk on which it has already been installed. As in a cold boot, the operating system will again ask to have the date and time entered.

 

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WORD GUIDE TO CHAPTER THREE

Bootstrap:

 A program that starts a computer.   

Cursor:

A patch of light or other visual indicator that shows where a person is working in a body of text.

DOS:

Disk Operating System. This is IBM’s version of the operating system1 which controls many of the functions of the computer.

Directory:

Tables of contents that lists programs and files that are stored sequentially on a diskette or hard disk. In short, a directory that describes the layout of records within a file.

Operating System:

A program or collection of programs that manages the hardware, output devices, logic operations and a number of other management functions. it provides a link between software and the computer’s internal language.

Security:

 The protection of information against disclosure, transfer, modifications, or destruction.

Write Protect:

 The process of protecting information stored on a diskette by sealing off the read/write notch with a tab or special tape. Some diskettes, such as those containing the operating systems, are  permanently sealed to prevent writing over their contents.

 

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SUMMARY OF COMPUTERS

While computers trace their lineage back several hundred years, most of the advances that led to modern computers have taken place since the late 1940s.

Most people think of computers as large cabinets with spinning tapes and blinking lights, which are locked behind security doors. This describes mainframe units—the large machines that process high volumes of information for businesses and governments. Since the invention of the microchip (very small transistors), a new generation of computers has become available. Known as personal or microcomputers, these machines have taken the same computing power that once required an entire room, and placed it in units that can sit on top of a desk or in a person’s lap.

Whether large mainframe units or the small micros, all computers operate in basically the same fashion. Computers are composed of the following functional sections:

Input

Central processing unit

Memory

Output

Input consists of the data to be processed, and the software program that provides the instructions and commands necessary for the computer to perform a specific job. These programs may be written by the computer’s operator, using a programming language that translates human instructions into a machine language the computer understands. Software programs that perform just about any task imaginable can also be purchased off the shelf.

The CPU is where the computer performs its arithmetic and logic functions, and where the operation of all the hardware is controlled.

Memory is where information (data) and instructions are stored. These are transferred between memory and the CPU by means of electrical conduits called registers.

There are two kinds of memory:

1. ROM

2. RAM

Read Only Memory can be read only by the computer itself. The computer operator has no control over it. It is the computer’s own software program, imprinted at the factory, to tell the computer how to work its own system.

Random Access Memory is under the operator’s control and is used to store information and instructions. The amount of RAM available (i.e., 64K, 256K, 640K), signifies the amount of filing-. cabinet space the computer has built into it, in which data can be filed, retrieved, and manipulated on a random basis. When the computer finishes processing the information it has been given, it returns it in the form of output. Output is made available through a printer, the video display unit, or by communicating it to another computer system. How does it all come together? The process starts by identifying a job that the computer can perform. A program is then chosen or created that will accomplish the tasks desired. The program will be written in a language the computer can understand, and that it converts to binary codes to actually carry out its assignment. All of this is governed by an operating system that tells the computer how to best perform the job, manages the filing system for storing the information, and operates the hardware needed to produce the work.

 

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Software

As noted earlier, there are software products for just about anything and everything imaginable. From games to programs designed to enhance professional development or monitor diet and nutrition, the list of possibilities seems almost limitless. Business software falls into the following categories:

Database management

Decision support

Word processing

Communications

Specialized use programs

Integrated software programs

DATABASE MANAGEMENT

Database management software allows for recording, modifying, and retrieving information without writing customized programs. Most database programs are designed to help users decide what type of information they want to record. They provide the means to enter, manipulate, and integrate the information to produce summaries, reports, or specific displays of items of interest. Most are set up to handle spur-of-the-moment inquiries, and allow records to be sorted and selected according to specific criteria. Examples of database software include PFS: File and Report and dbase III.

DECISION SUPPORT

The basic function of all decision support software, also known as financial modeling software, is to provide:

A quick and easy way to create mathematical models

Ways to enter information into the models

Reports of the results

These products can be broken down into three major categories: spreadsheets (VisiCa lc), financial modeling (IFPS), and integrated systems, which contain a database and graphing system (Lotus 1-2-3). All these products are designed to operate like an electronic multicolumnar accounting worksheet, except these worksheets have variable column widths with built-in math and financial models. Decision support software can be used to J)r1 pare budgets, analyze sales figures, calculate cash flow, or tiny other application where the information can be presented in a row or column.

WORD PROCESSING

Word processing packages allow for the creation, editing, and printing of documents, including correspondence and reports, form letters, legal papers, mailing labels, bills, and even book- length manuscripts. This book, for example, was written on a personal computer using one of the more popular word processing programs. The combination of word processing and personal computers offers more sophistication than can be found on a memory typewriter, and costs a fraction of the amount of a dedicated word processing system. The most fundamental component of any word processing package is its text editor. These editors are designed to edit a screenplay of text at a time, rather than line by line. They allow the user to scroll backward and forward through the text, rearrange it, copy it, delete words and phrases, add to an existing document, and, on some, check for spelling. Among the more popular programs are MultiMate, Word Star and the Volkswriter series.

COMMUNICATIONS

Personal computers that are linked together directly, or tied into host system, require the use of protocol software designed to allow two machines to talk with each other. A protocol is a standard that has been agreed to by hardware and software manufacturers so that different devices can transfer data between them. Without such a standard, two machines could not send or receive information at the same time or perform either function out of synchronization. A protocol provides a way for one machine to recognize that a line is tied up to the host, and that it must wait its turn. Protocols also provide the various sets of rules for controlling the transmission of information over any communications channel or cable.

Among the many functions protocol software programs perform are:

Establish and terminate the connection between two systems Maintain the integrity of the transmission through error detection procedures and requests for retransmissions Identify the sending and receiving machines handle a variety of special control functions, such as status checks, to make sure everything is working properly. Some software programs also provide a means to scramble and unscramble data communicated over telephone lines in order to protect the security of the information.

Among the more popular of these products are PC-Talk, Smart com II, and Crosstalk.

SPECIALIZED USE PROGRAMS

Specialized use packages fall into several groups:

Programs that support other software packages or enhance their use

Software that provides a specialized service, sometimes run- fling concurrently with another program

Graphics programs

Among the various packages available for specialized use are those that:

Run desktop organizers, which feature calculator, message board, telephone dialing, and appointment calendar functions that appear as windows similar to those shown in Figure 28, that overlay whatever software you may be working on. Print spreadsheet applications sideways so that they fit into reports more naturally. Increase the computer’s processing speed. Enhance keyboard operations by memorizing keystroke sequences and consolidating commands. With a program such as this, commands that normally take six or seven keystrokes can be reduced to one.

FIGURE 28. Monitor showing window display.

Produce presentation quality charts and graphs as shown in Figure 29.

Prepare line drawings, schematics, blueprints, and high resolution reproductions. The list of these specialized programs could go on. Most are available at a reasonable cost, usually for under $100, and many are offered free of charge through local personal computer user groups, or electronic bulletin boards.

 

INTEGRATED SOFTWARE

Integrated software programs offer several major functions in one package. Some of these offerings, for example, combine word processing, database management, and spreadsheets along with some form of communications. This is a one-stop-shopping approach, where you get everything in one place at one price. These are large programs that require substantial memory requirements on the order of 640K. Since they offer so much, they also have to scrimp in places to get everything in. This generally means that they can’t offer all the sophisticated features available in those programs that specialize in just doing word processing or spreadsheets. Two examples of integrated software are Symphony and Framework.

 

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