CST-091 CST-091 Click your left mouse button to continue . . . © Delta College CST Faculty Module Module 1 1 Introducti Introducti on to on to Computer Computer Systems Systems
CST-091CST-091
Click your left mouse button to continue . . .
© Delta College CST Faculty
Module Module 11
IntroductiIntroduction toon to
Computer Computer SystemsSystems
Input / Process / Output Input / Process / Output CycleCycle
Input OutputProcess
Storage
Data enters the computer.
In a payroll example, you key in 40 hours and a rate of $10.00 per hour.
The data is processed by the computer.
For example, the pay is 40 times 10.00 or $400.00
We need to see the answer – it is output.
For example, the $400.00 could be displayed.
We may want to store the results for end-of-year taxes.
The $400.00 could be stored on disk.
HardwareHardware
Physical parts of the computerPhysical parts of the computer The things you can “touch”The things you can “touch” The ProcessorThe Processor Input devicesInput devices Output devicesOutput devices Storage devicesStorage devices
ProcessProcess Using the data that is in memoryUsing the data that is in memory For example: CalculatingFor example: Calculating Processing HardwareProcessing Hardware
o Main MemoryMain Memoryo Central Processing UnitCentral Processing Unit
– Arithmetic/Logic UnitArithmetic/Logic Unit– Control UnitControl Unit
Main MemoryMain Memory Also Known As . . .Also Known As . . .
o Primary MemoryPrimary Memoryo Random Access Memory (RAM)Random Access Memory (RAM)
Holds program being runHolds program being run Holds data being processedHolds data being processed
BitsBits Memory made up of bitsMemory made up of bits BBinary Diginary Digitsits Small electronic componentsSmall electronic components Can be “On” or “Off”Can be “On” or “Off”
BitsBits
On --- has a value of 1On --- has a value of 1
Off --- has a value of 0Off --- has a value of 0
BitsBits
So memory is a bunch of one’s and zeros.So memory is a bunch of one’s and zeros.
1 1 111 00 0On Off Off OffOn On On On
ByteByte
A group of eight bits is called a byteA group of eight bits is called a byte So, this is a byte . . .So, this is a byte . . .
1 1 111 00 0
ByteByte
Look at these 40 bitsLook at these 40 bits
0100010001000101010011000101010001000001
Broken into groups of eights, they Broken into groups of eights, they become 5 bytesbecome 5 bytes
0100010001000101010011000101010001000001
The ASCII CodeThe ASCII Code
Each character is made up of 8 Each character is made up of 8 bits in a bytebits in a byte
So each byte contains a So each byte contains a charactercharactero A Number (0 1 2 3 4 5 … )A Number (0 1 2 3 4 5 … )o A LetterA Letter
– Upper Case (A B C … )Upper Case (A B C … )– Lower Case (a b c … )Lower Case (a b c … )
o A Special Character ($ # . , & … )A Special Character ($ # . , & … )
The ASCII CodeThe ASCII Code
Each character has its own Each character has its own pattern of bits – in a code pattern of bits – in a code
The code that is used is called The code that is used is called ASCIIASCIIo AAmerican merican SStandard tandard CCode for ode for
IInformation nformation IInterchangenterchangeo Pronounced: “Ask-ee”Pronounced: “Ask-ee”
The ASCII CodeThe ASCII Code
Look at these 5 bytesLook at these 5 byteso They contain 5 characters in ASCII CodeThey contain 5 characters in ASCII Codeo They happen to be upper-case lettersThey happen to be upper-case letters
0100010001000101010011000101010001000001
D E L T A
MemoryMemory
Measured in number of bytesMeasured in number of bytes K = KilobyteK = Kilobyte
o A “Kay”A “Kay”o A Thousand Bytes (1,000)A Thousand Bytes (1,000)
M = MegabyteM = Megabyteo A “Meg”A “Meg”o A Million Bytes (1,000,000)A Million Bytes (1,000,000)
MemoryMemory
So, if you have 16 “Meg” of RAMSo, if you have 16 “Meg” of RAMo You have 16,000,000 bytes of main You have 16,000,000 bytes of main
memory on your system!memory on your system! And, if your diskette is 1.4 MAnd, if your diskette is 1.4 M
o It can contain 1,400,000 characters!It can contain 1,400,000 characters!– (1.4 times 1,000,000 is 1,400,000)(1.4 times 1,000,000 is 1,400,000)
1. In the standard processing cycle of a computer, the step that happens first is __________.
A short quiz: Click on the best answer.
A Storage
B Input
C Output
D Process
?
1. In the standard processing cycle of a computer, the step that happens first is __________.A Storage
B Input
C Output
D Process
Whoops that’s wrong – please click here to try again.
1. In the standard processing cycle of a computer, the step that happens first is __________.A Storage
B Input
C Output
D Process
Good for you, you got that one right! Click FORWARD
2. Where does data have to be in order to be processed by the computer?
A short quiz: Click on the best answer.
A On the screen
B On the printer
C In RAM
D Next to the keyboard
?
2. Where does data have to be in order to be processed by the computer?
A On the screen
B On the printer
C In RAM
D Next to the keyboard
Whoops that’s wrong – please click here to try again.
2. Where does data have to be in order to be processed by the computer?
A On the screen
B On the printer
C In RAM
D Next to the keyboard
Yes, data has to be in main memory before it can be processed.
3. How many bits are in a byte?
Click on the best answer.
A 1
B 2
C 4
D 8
?
3. How many bits are in a byte?
A 1
B 2
C 4
D 8
Whoops that’s wrong – please click here to try again.
3. How many bits are in a byte?
A 1
B 2
C 4
D 8
Yes, each byte has 8 bits.
4. If a bit is “ON,” it has the value __________.
Click on the best answer.
A 0
B 1
C 8
D 1K
?
4. If a bit is “ON,” it has the value __________.
A 0
B 1
C 8
D 1K
Whoops that’s wrong – please click here to try again.
4. If a bit is “ON,” it has the value __________.
A 0
B 1
C 8
D 1K
Yes, an “ON” bit has a value of 1 and an “OFF” bit has a value of 0.
5. What is the code used to represent characters in a PC’s memory?
Click on the best answer.
A Bit-Byte
B IBM
C ASCII
D Mega-K
?
5. What is the code used to represent characters in a PC’s memory?
A Bit-Byte
B IBM
C ASCII
D Mega-K
Whoops that’s wrong – please click here to try again.
5. What is the code used to represent characters in a PC’s memory?
A Bit-Byte
B IBM
C ASCII
D Mega-K
Yes, the American Standard Code for Information Interchange.
6. Which is larger?
Click on the best answer.
A 1M
B 720K
?
6. Which is larger?
A 1M
B 720K
Whoops that’s wrong – please click here to try again.
6. Which is larger?
A 1M
B 720K
Yes, 1M is 1,000,000 bytes and 720K is only 720,000 bytes
7. How many bytes are needed to hold this: CST-091
Click on the best answer.
A 1
B 6
C 7
D 8
?
7. How many bytes are needed to hold this: CST-091
A 1
B 6
C 7
D 8
Whoops that’s wrong – please click here to try again.
7. How many bytes are needed to hold this: CST-091
A 1
B 6
C 7
D 8
Yes, there are 7 characters so 7 bytes are needed.
DataData
Raw facts you want to process and Raw facts you want to process and turn into meaningful informationturn into meaningful information
Data can be:Data can be:o NumbersNumbers 1 2 3 4 5 …1 2 3 4 5 …o LettersLetters A B C … a b c …A B C … a b c …o Special Characters $ & ! , ( ) …Special Characters $ & ! , ( ) …
InputInput
Entering data into the computer’s Entering data into the computer’s main memorymain memory
Translating data into a form the Translating data into a form the computer can understandcomputer can understand
Input devicesInput deviceso KeyboardKeyboardo MouseMouse
Input: The KeyboardInput: The Keyboard
Alphabetic keys like typewriterAlphabetic keys like typewriter Number keysNumber keys
o Across the TopAcross the Topo On Special Keypad on Right SideOn Special Keypad on Right Side
Special CharactersSpecial Characterso Often Upper Case of Other KeysOften Upper Case of Other Keys
Input: The MouseInput: The Mouse
A Pointing DeviceA Pointing Device Controls position of pointer on Controls position of pointer on
screenscreen Pointer appears as different objects Pointer appears as different objects
depending on what you are doingdepending on what you are doingo Arrow (pointing or selecting)Arrow (pointing or selecting)o Hand (pointing or selecting)Hand (pointing or selecting)o Hourglass (waiting)Hourglass (waiting)o etc.etc.
Basic Mouse Basic Mouse TechniquesTechniques
1.1. CLICKINGCLICKINGo Move pointer to item on screen & Move pointer to item on screen &
press/release left mouse button oncepress/release left mouse button once
Basic Mouse Basic Mouse TechniquesTechniques
2.2. DOUBLE-CLICKINGDOUBLE-CLICKINGo Point at item & press/release left Point at item & press/release left
mouse button twicemouse button twice
Basic Mouse Basic Mouse TechniquesTechniques
3.3. DRAGGINGDRAGGINGo Point at item, hold left mouse button Point at item, hold left mouse button
down while dragging to new location – down while dragging to new location – let mouse button uplet mouse button up
Basic Mouse Basic Mouse TechniquesTechniques
4.4. RIGHT-CLICKINGRIGHT-CLICKINGo Move pointer to item on screen & Move pointer to item on screen &
press/release right mouse button press/release right mouse button onceonce
OutputOutput
Presenting informationPresenting information We see the data that We see the data that
is in the computeris in the computer Output devicesOutput devices
o ScreenScreeno PrinterPrinter
Output: The ScreenOutput: The Screen
Also Known As:Also Known As:o MonitorMonitoro DisplayDisplayo CRT (Cathode Ray Tube)CRT (Cathode Ray Tube)
Displays:Displays:o Data being keyed inData being keyed ino Info from program processingInfo from program processing
Output: The PrinterOutput: The Printer
Prints info out on paper from Prints info out on paper from computercomputer
Called “Hard-Copy”Called “Hard-Copy” For Example:For Example:
o Non-impact Printer: Ink Jet PrinterNon-impact Printer: Ink Jet Printer– Does not strike the paperDoes not strike the paper– Can be colorCan be color
o Laser PrinterLaser Printer– Very High QualityVery High Quality
StorageStorage
Main StorageMain Storageo Holds program being runHolds program being runo Holds data being processedHolds data being processedo In the System UnitIn the System Unito Is VolatileIs Volatile
– Needs steady supply of electricity to Needs steady supply of electricity to keep its contentskeep its contents
– Pull the plug – start over!Pull the plug – start over!
StorageStorage
Secondary StorageSecondary Storageo ““Auxiliary Storage”Auxiliary Storage”
– Hard DiskHard Disk– In System UnitIn System Unit
– DisketteDiskette– PortablePortable
o Holds programs and data when not Holds programs and data when not being usedbeing used
Secondary StorageSecondary Storage
Hard DiskHard Disko ““Fixed Disk”Fixed Disk”o Inside System UnitInside System Unito Large CapacityLarge Capacityo Holds:Holds:
– Operating SystemOperating System– ProgramsPrograms– DataData
Secondary StorageSecondary Storage
3.5 Inch Diskette3.5 Inch Disketteo ““Floppy” or “Floppy Disk”Floppy” or “Floppy Disk”o PortablePortableo Relatively Small CapacityRelatively Small Capacity
– 1.4 M (1,400,000 bytes)1.4 M (1,400,000 bytes)
o Usually Holds DataUsually Holds Data– Can Transfer Data to Other SystemsCan Transfer Data to Other Systems
Secondary StorageSecondary Storage
3.5 Inch Diskette3.5 Inch Disketteo Write-Protect SwitchWrite-Protect Switch
– Protect Data From ErasureProtect Data From Erasure
o Lower-Right Corner of BackLower-Right Corner of Back– Sliding Black Plastic SwitchSliding Black Plastic Switch– UP (Closed)UP (Closed)
– Can Read or WriteCan Read or Write
– DOWN (Open Square)DOWN (Open Square)– Can ReadCan Read– CAN’T Write!CAN’T Write!
ReadRead
WriteWrite
Not Not ProtectedProtected
Read Read OnlyOnly
Protected!Protected!
Suppose you are running a payroll Suppose you are running a payroll program on your computer.program on your computer.
The program will ask you for John The program will ask you for John Doe’s data – how many hours he Doe’s data – how many hours he worked and what his rate of pay is.worked and what his rate of pay is.
Once the program has John’s data, it Once the program has John’s data, it will calculate his pay.will calculate his pay.o For example, if John worked 40 hours at a For example, if John worked 40 hours at a
rate of $10.00 per hour, he has $400.00 rate of $10.00 per hour, he has $400.00 coming to him – before all the deductions coming to him – before all the deductions are taken out!are taken out!
Once John’s pay is calculated the Once John’s pay is calculated the program needs to print his check.program needs to print his check.
Also, the program needs to store Also, the program needs to store John’s pay information for later tax John’s pay information for later tax processing.processing.
Another Short Quiz …Another Short Quiz …
On the next few screens, you will On the next few screens, you will be presented with several steps be presented with several steps in the Input / Process / Output / in the Input / Process / Output / Storage cycle.Storage cycle.
Click in the diagram for the step Click in the diagram for the step you are in.you are in.
8. You are sitting at the computer with John Doe’s time ticket – and you need to get his data into the computer: his hours worked and his rate of pay. Click on the step you are in …
Another short quiz: Click on the best answer. ?
PROCESS
STORAGE
OUTPUTINPUT
8. You are sitting at the computer with John Doe’s time ticket – and you need to get his data into the computer: his hours worked and his rate of pay. Click on the step you are in …
PROCESS
STORAGE
INPUT OUTPUT
No – please click here to try again.
8. You are sitting at the computer with John Doe’s time ticket – and you need to get his data into the computer: his hours worked and his rate of pay. Click on the step you are in …
PROCESS
STORAGE
INPUT OUTPUT
YES! You are INPUTTING John’s data. Click FORWARD
Probably on the keyboard
9. Once John’s data is input, it is processed in the CPU by the payroll program. Once John’s pay has been calculated, his pay check is printed. Click on the step you are in now…
?
PROCESS
STORAGE
INPUT
Click on the best answer.
OUTPUT
9. Once John’s data is input, it is processed in the CPU by the payroll program. Once John’s pay has been calculated, his pay check is printed. Click on the step you are in now…
PROCESS
STORAGE
INPUT OUTPUT
No – please click here to try again.
9. Once John’s data is input, it is processed in the CPU by the payroll program. Once John’s pay has been calculated, his pay check is printed. Click on the step you are in now…
PROCESS
STORAGE
INPUT OUTPUT
YES! The check is OUTPUT on the printer.
Pay Chec
k
By the way, which step would you be in if there was a problem with John’s data – for example, we tried to input –10 hours or he owed more on his deductions than he made? See my hint in the bottom left corner …
PROCESS
STORAGE
INPUT OUTPUT
The OUTPUT step: An error message would be displayed on the screen.
Error Message
10. Uncle Sam and the Governor want us to keep track of John’s pay – so he can pay the correct taxes at the end of the year. If we save John’s payroll data, which step are we in?
Click on the best answer.
?
PROCESS OUTPUTINPUT
STORAGE
10. Uncle Sam and the Governor want us to keep track of John’s pay – so he can pay the correct taxes at the end of the year. If we save John’s payroll data, which step are we in?
PROCESS
STORAGE
INPUT OUTPUT
No – please click here to try again.
10. Uncle Sam and the Governor want us to keep track of John’s pay – so he can pay the correct taxes at the end of the year. If we save John’s payroll data, which step are we in?
PROCESS
STORAGE
INPUT OUTPUT
YES! You are STORING John’s data.Click FORWARD
Probably on the hard disk
SoftwareSoftware
Instructions that direct the Instructions that direct the operations of the computeroperations of the computer
A “Computer Program”A “Computer Program” Two Main CategoriesTwo Main Categories
o Application SoftwareApplication Softwareo System SoftwareSystem Software
Application SoftwareApplication Software
Performs specific tasks for youPerforms specific tasks for you Tasks are called “Applications”Tasks are called “Applications”
o Word ProcessingWord Processingo SpreadsheetSpreadsheeto DatabaseDatabaseo CommunicationsCommunicationso GraphicsGraphics
Systems SoftwareSystems Software
Programs that manage the Programs that manage the computer and its devicescomputer and its devices
Perform chores for youPerform chores for you The “Operating System”The “Operating System”
o e.g. Windowse.g. Windows
Systems SoftwareSystems Software
An Interface between you and An Interface between you and the computer hardwarethe computer hardware
An Interface between your An Interface between your application software and the application software and the computer hardwarecomputer hardware
The Operating SystemThe Operating System
An Interface between you (or An Interface between you (or your application) and the your application) and the computer hardwarecomputer hardware
Starts and Initializes the Starts and Initializes the computer (“booting”)computer (“booting”)
Coordinates system’s access to Coordinates system’s access to various devices (keyboard, various devices (keyboard, screen…)screen…)
11. What is another name for “Software?”
Click on the best answer.
A System
B CPU
C Computer Program
D Processor
?
11. What is another name for “Software?”
A System
B CPU
C Computer Program
D Processor
No – please click here to try again.
11. What is another name for “Software?”
A System
B CPU
C Computer Program
D Processor
Yes, Software is a Computer Program.
12. Which kind of software controls the hardware?
Click on the best answer.
A System Software
B Application Software
?
12. Which kind of software controls the hardware?
A System Software
B Application Software
No – please click here to try again.
12. Which kind of software controls the hardware?
A System Software
B Application Software
Yes, System Software controls the hardware for you.
13. Which kind of software does some work for you – that is, which kind performs tasks for you?
Click on the best answer.
A System Software
B Application Software
?
13. Which kind of software does some work for you – that is, which kind performs tasks for you?A System Software
B Application Software
No – please click here to try again.
13. Which kind of software does some work for you – that is, which kind performs tasks for you?A System Software
B Application Software
Yes, Applications like Word Processing to create a letter.
© Delta College CST Faculty