Presentation is loading. Please wait.

Presentation is loading. Please wait.

CPSC- 120 Principle of Computer Science I Computer = Hardware + Software.

Similar presentations


Presentation on theme: "CPSC- 120 Principle of Computer Science I Computer = Hardware + Software."— Presentation transcript:

1 CPSC- 120 Principle of Computer Science I Computer = Hardware + Software

2 Hardware b Main Memory b Secondary Memory b Central Processing Unit (CPU) b Input Devises b Output Devises

3 Main Memory b Random Access Memory (RAM) b storing information and programs b information such as numbers, names, lists, pictures b An ordered sequence of storage locations called memory cell b each memory cell has associated with it a unique address

4 Secondary Memory b Additional storage capability on most computer such as a disk drive b hard disk, floppy disk, CD b inexpensive b more information can be stored measured by megabyte or gigabytes

5 Central Processing Unit (CPU) b Control computer operations b Perform arithmetic and logical operations b each operation is performed less than one millionth of a second b To process a program, CPU fetches each instructionfetches each instruction decodes the instructiondecodes the instruction executes the instructionexecutes the instruction

6 Input and Output Devices b Output Monitor, PrinterMonitor, Printer b Input Keyboard, MouseKeyboard, Mouse

7 Software b Operating Systems- - UNIX, Windows b Application Programs - - Word Processor, Spreadsheet b Software Development Tools - - compiler, editor

8 Steps in the Software Development Method b Problem Specification b Analysis b Design b Test Plan b Implementation or coding b Testing

9 Case Study b Refer to page 21

10 Programming languages b Machine Languages b Assembly Languages b High-Level Languages

11 WITH Ada.Text_IO; PRODECURE Hello IS -------------------------------------------------------------------- -- A very simple program; it is just displays a greeting. -- -- ---------------------------------------------------------------- BEGIN -- Hello Ada.Text_IO.Put(Item => “Hello there. “); Ada.Text_IO.Put(Item => “We hope you enjoy studying Ada!”); Ada.Text_IO.New_Line; END Hello; Example Ada Program

12 Chapter 3 The General Structure of Ada Programs

13 Displaying Initials Program WITH Ada.Text_IO; PROCEDURE Hello_Initials IS ------------------------------------------------------------ --| Requests, then displays, user's first and last initials. --| ------------------------------------------------------------ Initial1 : Character; -- objects that hold initials Initial2 : Character;

14 Cont. BEGIN -- Hello_Initials -- Prompt for (request user to enter) user's initials Ada.Text_IO.Put(Item => "Enter your two initials> "); Ada.Text_IO.Get(Item => Initial1); Ada.Text_IO.Get(Item => Initial2); -- Display user's initials, with a greeting Ada.Text_IO.Put(Item => "Hello "); Ada.Text_IO.Put(Item => Initial1); Ada.Text_IO.Put(Item => Initial2); Ada.Text_IO.Put(Item => ". Enjoy studying Ada!"); Ada.Text_IO.New_Line; END Hello_Initials;

15 Reserve Words and Identifiers b Reserve Words WithProcedureISBeginEND

16 b Predefined Identifiers Ada.Text_IOPutNew_LineCharacterGet

17 Displaying the User’s Name WITH Ada.Text_IO; PROCEDURE Hello_Name IS ------------------------------------------------------------------------ --| Requests, then displays, user's name --| ------------------------------------------------------------------------ FirstName: String(1..10); -- object to hold user's name

18 Cont. BEGIN -- Hello_Name -- Prompt for (request user to enter) user's name Ada.Text_IO.Put (Item => "Enter your first name, exactly 10 letters."); Ada.Text_IO.New_Line; Ada.Text_IO.Put (Item => "Add spaces at the end if it's shorter.> "); Ada.Text_IO.Get(Item => FirstName); -- Display the entered name, with a greeting Ada.Text_IO.Put(Item => "Hello "); Ada.Text_IO.Put(Item => FirstName); Ada.Text_IO.Put(Item => ". Enjoy studying Ada!"); Ada.Text_IO.New_Line; END Hello_Name;

19 Ada’s Capabilities b Control Structures b Data Structures b System Structures

20


Download ppt "CPSC- 120 Principle of Computer Science I Computer = Hardware + Software."

Similar presentations


Ads by Google