Một số câu hỏi về máy tính

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1 Co m p uter system Co m p uter Syste m Book m p uter I:co syste m funda m e ntals. Chapter INTR O D U C TI O N O M P U T E R. 1: TO C Q uestion . W h at co m p uter? 1 is a A co m p uter m a y be defined as a m ac hine which accepts data from an input device, processes it by performing arithmetical and logic operations in accordance with a progra m instructions of and returns the results through an output unit. A m p uter co is basically an electronic ac hine m operating on current. Q uestion . Co m p o n e nts a m p uter 2 of Co system? A m p uter co system m prises the co of following m p o n e nts: co 1. Central Processing Unit (CP U). - C P U heart the whole sys is the of
2 - CP U consists the of : • control unit (CU) • arithmetic logic unit (ALU) • accu m ulator (AC C) • progra m counter (PC) • instruction register (IR) • m e m ory address register(MA R) • m e m ory data register (M D R) • status register (SR) • general purpose register - The function each m p o n ents C P U: of co of • Control unit:  control and co_ordinate allhardware functions the S. of C  exa mine and decode all progra m instructions to the co m p uter and initiate their execution by sending the appropriate signals. • AL U:  performs all arithmetic and logic m p arision co two values functions required co m p uter. by • A C C:  holds the firstoperand the of temporary resultof the U. AL • P C:  contains the add the of next instruction be to excuted. • IR:  contains the current instruction be to executed. M ain e m ory m • M A R:  holds the address location to or from which data is to be transferred • M D R:  contains the data to be written to or read out of the addressed location. • S R:  keeps track the of status the of accu m alator. • G e neral Purpose Register:  for general purpose procedures. Please refer to diagra m lustratin of for an il the basic m p o n ents the P U. co of C
3 P U C I N Control unit T E Arithmetic Logic Unit R Accu m ulator N A Progra m Couter to L m ain Instruction Register B U m e m ory S M e m ory Address Register M e m ory Data Register Status Register e n eral G Purpose Register Basic m p o n ents a P U. co of C Control Unit Input Unit U O utput AL Unit M ain e m ory M Backing Storage Control signals Data flow Co m p o n e nts a S. of C 2. Input units - Used to enter data( raw unprocessed facts) and instructions to the co m p uter. 3. O utput units - Used for delevering the processed resultfrom the m p uter useful form. co in 4. Backing storage units - Backing storage units need for high capacity data storage devices that can store data in a m ore permanent form for later retrieral, updating and referencing. - Backing storage is also called secondary storage external storage and auxiliary storage.
4 Chapter MIC O P R O C E S S O R. 2: Q uestion . Cache e m ory? 1 M - Cache e m ory s m all a m o u nt very m is a of fast store with faster access time than the ain e m ory. m m - Cache m e m ory is used to temporaryty store data instructions that are likely to be retrieved a ny m times, thus speeds up the processing data. of - Sits between m ain storage and the processor acting as holding area through which alldata and instructions pass. - Old data the in cache e m ory m is over written ne w by then cache is full. Q uestion 2. Virtual M e m ory? - Virtual m e m ory m ak es both the m ain e m ory backing store. use of m and - In a virtual e m ory sys, each user has the illusion that his progra m is in m the ain e m ory m m allthe time. - The sys m aintains this illusion by keeping so m e of the “unused” portion of the progra m’s code and data on a backing store device which is usually m a g n etic disk - The m ov e m e nt of the unused portion from the backing store to the mian m e m ory is transparent the to users. - Please refer to diagra m for virtual m e m ory. Backing Store M ain e m ory M A3 A2 A1 A3 A2 A1 Virtual M e m ory Chapter B A T C H/ N LINE N D A L 3: O A RE TIME O C E S SI N G S T E M. PR SY Q uestion 1. Batch Processing Syste m ? - Def: m p uter Co processing does not begin untilallthe input data has been collected and grouped together called Batched G e nerally data is accu m ulated certain for a period time unitla of or certain quantity. - Ads:  Response time is not critical.  Need process to large volumn data. of  Co m p uter efficiency ore is m important than response time. - Dis:  Time between recording and processing source of docu m e nt is long  Rereen normally required iferrors are encountered.  Data is not current.  Error correction ore is m difficult.
5 Q uestion nline 2. O Processing Syste m ? - Def: Inputs data enters the co m p uter directly as soon as it is being transacted. There information willbe processed m e diately im and updated into the a ster m file. - Ads:  Enter availabili information tyof for decision a king. m  M ore accurate data capture.  Schedules suits user. - Dis:  CP U time is used less efficiently.  Rando m arrival of transactions, terminal operator process each transaction separately.  M ore expensive than batch processing. Q uestion 3. Real Time Processing Syste m ? - Def: O n e which controls the environm ent by receiving data processing the m and returning results sufficiently quickly to affect the functioning of the environ m ent that at time. - Ads:  Response time is very criticaland sufficient quick. - Dis:  Expensive hardware & software.  Very m plex terms hardware co in of & software. Chapter P RINTE R S N D R MI N A L S. 4: A TE Q uestion 1. Classification printers? of 1. Classifying printers according speed. to a. Serial printers Slow printers that print one character a at time. Eg: Dot atrix m printers Daisywheel printers b. Line printers M e diu m to high speed printers that can print in excess of 2000 lines per minute. Eg: Chain Printers Band Printers Dru m Printers 2. Calssifying printers according m ethod printing to of a. Impact printers Use m m ers prints strike ha or to a print rebbon order form in to the character on the paper. b. Non impact printers Use ore m silent m ethods printing. of Eg: Ther m al printers Ink Jet printers Lazers printers 3. Classifying printers according print quality to Kinds quality printers of Draft quality Near letter quality(NL Q)
6 Letter quality Graphic quality Q uestion 2. Describe m e so types printer? of 1. According speed: to a. Dot atrix m printer - Serial impact printers that can print draft,near letter quality and a limited a m o u nt graphics. of - The print resolution is generally lower than lazer printers. b. Daisywheel printers - Are serial impact printers, the speed of a daisywheel printer is slow(2055 characters per second), noisy operation. in - The print head has the letters arranged at the end of spokes round a central hub. c. Chain printers - The chains printers has its characters set rapidly rotating print chain. on a d. Band printers - The band printer has rotating scalloped steel band. e. Dru m printers - Are line printers, the print character are raised in bands around a heavy m etal dru m which rotates very at high speed. - The print ha m m ers strike the paper and a print ribbon against an apropriate character on the line. An entire line of the sa m e character is printed on one rotation the of dru m. f. Ther m al printers - Uses special heat sensitive paper and a m atrix of print wires that beco m e hot when exposed an to electric current. The heated wires m e co into close contact with the paper, burning the image the of character onto it. - The ore m advanced thermal printers are using thermal transfer printing. - They have a special heat sensitive ribbon and a print head with wires that beco m e hot when currents a is applied. - The heat from the print wires causes the ink from the ribbon to fuse to a piece regular of paper. g. InlJet Printers - The ink jet prints by using a s m all droplet generator to break special inks into tiny drops, which are then forced towards paper a supply. h. Lazer printers - Using photoconductive m. a dru - A lazer is then used write to the image the of character onto the dru m. - After exposure to the lazer, the dru m rotates through a developing station, picks up toner and transfers the itto paper. - The character is fused onto the paper heat. by i. Ion deposition printers - Ions are created in a cavity, and directed electrically through an orifice onto the dielectricsurface a of rotating cylinder. - The required characters are formed as an electric charge image on the cylinders surface. - Toner is the applied to the charged image and transferred to the paper on which itis transfixed pressure(cold by fusion). j. Electrostatic printers
7 - Letterheads and logos are created electrostatically from a changeable m etal cylinder. k. M a g n etic printers - A dru m in the printer has a surface that can be coated with sows of tiny spots m a g n etion m e a ns thousands minute of by of of recording heads. - As the dru m rotates itbeco m e s covered with these m a g n etic spots so as to from latent image the a of page be to printed. - Dry ink particles are brought into contact with the dru m’s surface and these adthere the a g n etised to m spots. The ink was then pressunal on to the surface and subsequently transferred onto the paper. Q uestion 3. Characteristics of page a printers? - Speed - Characters sets - Copies - Intelligence - O utput Chapter D A T A O R A G E E DIA. 5: ST M Q uestion 1. Data storage Requirements Characteristics? - Lo w access time: fast speed - Storage capacity:m uc h enough - Interchangeability:can be change easily - Security:safe enough - Transfer rate: fast enough - Cost: econo mic Q uestion a g n etic 2. M disks? - This co m prises a drive unit onto which one or perhaps two m a g n etic disk cartridges are loaded. - The drive consists of a control unit and a spindle housing that rotates continuously when switch on. - The cartridge are loaded by the operator so as to provide the data currently needed for the job hand. in - Bach tracks is devided up into sectors(often 4 or 8), sectors are read or written m ore a or at time blocks m e a ns a as by of read. - There are usually one head for each surface, allthe heads are ov ed. m - Sunchronously across tracks. the - O nce in position allthe data on the equiradial tracks can be read or written without further o ve m e nt the m of heads. - Cylinder set equiradial tracks. is a of - A cartridge co m prises several flat disks m o u nted on a central sprindle. W h e n o u nted m itrotates a at high speed enabling data be to read from or written to it. The data is recorded m a g n etically on both surfaces of each disk the in form concertric tracks. of •  Certain m o d els of disk units also have a nu m b er of fixed read/write heads addition the o vable in to m heads.  The fixed head are positioned permanently over certain of the outer tracks, there being one head per track, so climimating the need for head o ve m e nt. m - The heads are very close disk surface.
8 - Curshion air carried the of by rotating disk. Q uestion 3. Winchester disks( hard disks )? - Co m prises a nu m b er of platters(disks) permanently into an airtight enclosure. - All dust is excluded thus perimiting the read/write heads to be positioned even closer the to surfaces and so enabling greater recording densities to be m ployed. e - The disks have greater storage capacity and a higher rate of data transger. - It has the lubricated surfaces allowing the heads “land” when the platters cease rotate, so to eliminating head crashes. - Winchester platters are either in, 5 ¼ in 3 ½ in 14 in, 8 or diameter. Q uestion 4. Floppy disks? - Diskettes, generally called floppy disks, are single disks m a d e of flexible plastic and permanently housed is an envelope. - The data on floppy disks is in concentric tracks on the outer part of the surfaces and access itis via to slot in the envelope. - The m ost co m m o n size are 3 ½ in, 5 ¼in, and 8 in diameter disks, the 3 ½ in disks have the advantages a of shutter. - Floppy disks m ay be either single or double sided and of course the drive needs be to correspondingly equipped. - Both the drives and the floppy disks themselves are inexpensive with the result that they have co m e into extensive used by s m all business and ho m e m p uter co buffs. - The range of capacities is from 1/4 to 2 m e g a bytes and transfer rates around 125 250 to kilobytes per seconds. Q uestion ptical disks? 5. O - O ptical disk are m p aratively w co ne develop m e nt for data storage. - O ptical disks consist of a single removable glass, plastic or m etal disk coated on one side with tellurium and protected by a 1 m m layer or transpacent plastic. - The disk diameters are m o stly between 8 in and 14 in they rotate on a spindle a in similar fashion m a g n etic to disks. - The data is recorded in the form of minute pits burned into the telliurium coating a by finely focused lazer bea m. - O ptical disks hold between 0.7 and G B s, this is about 20 times greater than a g n etic m dis cartridges. - The data is read by a low po wer laser bea m which m ov ed across the surface and is reflected into photo a cell. - O ptical disks rotate m o stly at 1500 r.p.m which, allowing for the m ov e m e nt of the laser unti, given access time of between 16 & 500 m s and data transfer rates 0.6 3 V s of to M per second. - The draw back of optical disks is that the data cannot be erased so m a king them nonrewriteable. Q uestion a ss 6. M storage e dia? m - M a ss storage m e dia is a high capacity disk system as when necessary by transferring data from nu m b er “data a of cartridges” house cells. in - Each cartridge consists of a 3 in wide m a g n etic m o diu m inside a protective cover
9 - In order to load the disk system, the data cartridges are m ov ed auto m atically from the cells. - A typical system consists of 9440 cartridges giving a storage capacity of 472000 million bytes. Q uestion a g n etic 7. M dru ms? - A m a g n etic dru m consists of a cylinder upon the surface of which data is stored in m a g n etic form in tracks running around its circumference, each track has its own read/write head. - A typical m a g n etic dru m has 800 tracks each capable of holding 5000 bytes. Q uestion 8. Charge_coupled Device e m ory M (CC D)? - C C D consists of thousands tiny m etal squares each capable of holding an electric charge, thus representing bit. a - The squares are the in form an of array 64 64 x holding 4096 bits. - Itis very impact. - C C D is volate litystorage. Q uestion a g n etic 9. M Bubble e m ory? M - A thin wayer of m a g n etic garnet is capable of containing tiny do m ains or cylinders m a g n etism, of called bubbles. - By erasing un w anted bubbles, the resultant presence of a bubbles represent 1 a bit. a or 0 - The m ain ads are low po w er consu m ption, co m p actness, robustness reliabil tyand i nonvolit l ty ii . Q uestion e g n etic 10. M tape? - The m a g n etic tape usage is no w m ore as a backup m e diu m rather than a primary ethod backing m of storage. - Itis often used a as depositony for disk m p e d du from fixed data storage. - Itis in reells of up 3600 feet and is m a d e of M ylar plastic tape, 1/2 in wide and coated with m a g n etic aterial on a m one side. - The data is read from one read and written another. to - A reel of tape is loaded on a m a g n etic tape drive, and so as m a ny drives are needed reels as during processing a run. - Itis used a as backing e diu m m than primary ethod backing a m of storage. - The seconds usually have be to sequence where store m a g n etic in tape. Chapter C O M P U T E R 7: FILES. Q uestion 1. File Processes? 1. Sorting a. The records logical file are in brought into m e so sequence as determined by key the in records. b. A m p uter co is capable sorting of record into “nested” a sequence. c. Sorting is done by a “sorting generator”. This is part of the co m p uter’s software and co m prises several sophisticated sorting techniques that are called into use according the to fileand the sort requirements. d. The need sorting of has dimished line in with the mise m a g n etic de of tape as backing storage. 2. M erging - M erging implies that two m ore or files in the m e sa sequence are m bined co into one file. a. File erging m
10  T w o or m ore separate files of similar seconds and in the sa m e sequence are m arged together so as to form one file. b. Record erging m  The records from two or m ore “input” files, usually in the sa m e sequence, are co m bined one record in the output file. 3. M atching a. T w o or m ore input files (generally in the sa m e sequence) are co m p ared records against record in order to ensure that there is a co m plete set of records for each key. b. M a s m atched records are highlighted for subsequent action 4. Su m m a nizing a. Records with the sa m e key in one file are accu m ulated together to form one record the in output file. b. Su m m a nizing usually applies to a file presorted into a certain sequence and the resultant fileis in the m e sa sequence. c. Records be m m arized to su are generally of similar type. a 5. Searching a. Searching is looking for records with certain keys or holding certain data and so m e in way a king note these. m a of b. An instance is a search for and count allrecords of with a debt balance of above certain m o u nt. a a 6. Information retrieval a. Information retrieval is the process that involves the bringing together of data from several files. b. Data a y m also be extracted from several files and m bined co before being presented information. as Chapter DIRE C T C C E S S 8: A FILE R G A NIZ A TIO N N D R U C T U R E S. O A ST Q uestion 1. Storage and Access o d es? M There are principal m o d es 3 for storing and accessing accords disk dru m: on a or 1. Serial m o d e: - The record are stored contigously regardless their keys of - The sole way of accessing serial seconds is to search through the co m plete filestarting with the firstrecord. - It is so m etimes possible to partition a serial files thus reducing the search time starting by the search the at beginning a of kno wn partition. - A serialfileis normally of a temporary nature awaiting sorting into a useful sequence. 2. Sequential m o d e: - direct access sequential m o d e normally involves accessing sequential a filethat is stored sequentially. - sequential m o d e is often associated with a m a ster file held in a certain sequence and updated by a transaction file sorted into the sa m e sequence. 3. Indexed_sequential/selective_sequential m o d e - Indexed_sequential is a m o d e of storage where by records are held sequentiallyand accessed selectively. - Groups unrequired of records are skipped past.
11 - Indexed sequentialfiles ay m also be accessed haphazandly. 4. Rando m o d es: m - Each record is stored in a location determind from the second’s key by m e a ns an of add generation algorithm. - The only erricient way find record use to a is to the algorithm - Rando m o d e m is applicable m a ster to files • Ads rando m o d es of m  No index is required thus saving storage space  It is a fast access m ethod because lit le t or no searching is involved  Transaction do not need storing, thus saving time  Ne w records are easily insertly into the rando m file provided they are not excessive nu m b er in • Dis  The m ain problem with the rando m m o d e is in achieving a uniform spread of records over the storage are allocated to the file Q uestion 2. Direct Access Addressing? - The key record of is used identify by to record - The key record of also is used decide to its storage location(or address) 1. Self addressing: - Self addressing is a straight forwards m ethod because a record’s address is equal its key’s to value - The fileis inevitably stored key in sequence • Ads self addressing of  Itleads directly to the wanted record  No indexing searching or is required  The key itselfneed not necessarily be held within the stored record although itgenerally is • Dis  The storage space per second has be to the m e sa  W h e n records one missing, storage locations related to its m u st m pty be lefte 2. Self addressing with key conversion - This m ethod a basically similar to self addressing except that the key required lit leprocessing turn a t to itinto the record’s address - This leads either pricise to a address 3. M atrix addressing - In so m es case, it is necessary to find the add of a record held within a m ultidimensional atrix record m of it’scalled atrix m addressing. Q uestion 3. Direct Access Searching? - W h ere as addressing determines the location of a record by using algorithmic m ethods, searching finds the record by scanning groups of records, and index, both. or - ]The simplest m ethod is to exa mine every record a file until the required record is found shortcut a is generally desiable. 1. Indexed sequentialsearching - A cylinder index is created hold highest cylinder’s to the key
12 - Associated with each cylinder is a block index holding the highest key in each block within that cylinder - When searching record’s for a key the in index  The cylinder index is exa mined key_by_key until one is found that is larger than or equal to the wanted key this directs the search the to appropriate block index  The block index similarly exa mined a and the search The block is searched record by record until the wanted record is found 2. Binary searching( binary chopping ) - The key in the index to be binary search m u st be in sequence and form a co m plete set - The search starts at the midpoint of the index and then m o ves half way to the left or right(down or up) depending upon whether are wanted key is less than greater or than the midpoint key - In pracice, the index is unlikely to as convenient as this exa m ple because it is not always possible to exactly halve each sucessive m ov e(co m plete exact holvingis possible only when the total nu m b er keys the of in index is 0 2 1) - The average nu m b er of exa minations co m p arisons is (log2 k) 1 ( is the k nu m b er keys the of in index) 3. Block searching - A block is a subdivision of an index. A block is devised to contain, roughly the square root the m b er keys the of nu of in whole index - The search is first through the block index to find the appropriate block and then through this to find the wanted key - The average nu m b er of exa minations is square – root – k (k is the total nu m b er keys) of 4. Balanced binary tree searching - A binary tree is a relationship of keys such that the exa mination of any key leads one two to of other keys - The binary tree is actually in the form of an index containing all the keys together with a directory sho wing the braches stem ming leftand right from each key - Binary tree searching is suitable for an unsequenced file - The search is similar to binary searching in that each key exa mination holves the rinaining keys, on average Chapter 11: INTR O D U C TI O N O R TIFICAL T A INTELLIGE N C E. Q uestion 1. AI? AtificialIntell igence Ithas three braches 1. Expert systems (or kno wledge base system) - E Ss are progra ms that contain the kno wledge of hu m a n expert, encoded so a co m p uter can understand it with encated kno wledge seasoning m a chinism, E S can tackle problem that are beyond the seach of conventionally progra m m e d m p uters. co 2. Natural language systems (everyday native language) - Natural language systems are progra ms that understand the native language the of user, such E as
13 - The m o st popular natural language systems are those that act as interfaces data to bases 3. Simple perception systems (for vision, speed and touch) - They can interpret visual scenes and decide if object m e et inspection standards and quality control criteria, or m o ve a robot to the proper location grasp part for m a n ufacturing ot a Q uestion h o 2. W does the updates? - Updating the kno wledge bases is very diffirent when with updating databases because of the difference the in type of information and the in cause and effect relationship contained kno wledge in bases - A kno wledge in the area, when databases m a y be m o dified by a normal users Chapter 12: P E R T S T E M S. EX SY Q uestion h at S( 1. W is an E Expert system )? An E S is a kno wledgeintersive progra m that solves a problem that normally requires hu m a n expertise • Characteristics of Ss E - They solve problems well as better than m a n as or hu experts - They use kno wledge the in form rules frames of or - They can consider ultiple m hypotheses simultaneouly • Types E S of - An assistant  Is the leasts expert lowest or level E Ss  It helps a decision m a ker by doing routine analysis and porting out those portion the of work where m a n hu expertise is required - A colleage  The ne w discusses the problem until joint decission is a reached  W h e n system is going wrong, the user adds m ore information get to itback on track - True S E  Is system a that advises the user without question  There are no practical areas today which in decission Q uestion S 2. A E Life Cycle (ESL C)? - An accepted D L C S for expert systems has yet be to developed There are phases 6 lifecycle an S in E 1. Phase1 Selection an – of Appropriate Proble m - Phase 1 involves finding an appropriate problem for an E S, indentifying an expert contribute to the expertise - Establishing a preliminary approach - Analysing cost and the benefitsPreparing develop m e nt a plan 2. Phase – 2 Develop m e nt a of prototype system - A prototype sys is a s m all version of an E S designed to test assu m ptions about ho w to encode the facts, the relationships and the kno wledge of experts
14 - The prototype permits the kno wledge engineer to gain the expert’s co m mitm ent and to develop a deeper understanding of the field of expertise - Other subtasks this phase: in  Learning about the m ain do and the task  Specifying performance criteria  Selecting S an E building tool  Developing an implementation plan  Developing detailed a design co m plete for a system 3. Phase – 3 Develop m e nt a m plete of Co Syste m - The ain m work this phase in is the addition a of very large m b er rules nu of - The kno wledge base has to be expanded to full kno wledge base appropriate the to real world and the user interface has be to developed 2. Phase – 4 Evaluation the of system - This phase involves testing the system against the performance establised in earlier stages 5. Phase – 5 Intergration the of system - The E S has to be intergrated into the data flow and work patterns of the organization - In this stage, the expert system has to be interfaced with other databases, instruments and hardware. 6. Phase – aintenance the 6 M of system - The m aintenance of the E S involves is updating, charging in the system when operating. W h e n operating, m ore problems occur the in system, it so is necessary continue to take care the system by expert a in fix period of time - So expert system, are so co m plex that in a few year the m aintenance costs willequal the develop m e nt costs. B O O K m p uter II:Co syste ms architecture. Chapter – N U M B E R A S E S. 1 2: B Q uestion m m o n m b er 1. Co nu bases used co m p uter in hardware operation? • Decimal(denary) system: - The base is ten – there are 10 different sy m b ols, the digits 0, 1, 2, etc...upto 9 - To represent value less than ten involves only one digitlarger values need two m ore or digits • Binary system - The base u st m be two, with only the digits 0 and available 1 - To sho w values two ever of or require two m ore or binary digits • Octal system - Octal system has eight its base, as ituses the m b ol 1, up 7 sy 0, 2 to only - T w o m ore or digits are needed for values eight of and above • Hexadecimal system(hex) - Hexadecimal system has sixteen its base, as ituse the m b ols 1, sy 0, 2...,9 & A, B, C, D, E, F, to stand for the “digits” ten, eleven, twelve, thirteen, fourteen, fifteen. Q uestion 2. Converting from Bases To Bases? 1. Change the decimal
15 - Binary: Eg. (2559) 10 2559 1 1279 1 639 1 319 1 159 1 1 (2559)10 = (10111111111) 2 79 39 1 1 19 9 1 4 0 2 1 0 0 - Octal: 7690 8 49 96,1 8 10 16 120 8 2 1 15 8 40 0 7 1 (7690)10 (17012)8 = - Hexadecimal: 6396 16 159 399 16 156 79 24 16 1 1 8 1 C F (6369)10 = (CF81) 16 2. Convert others to from binary - To decimal (101010)2 (?)10 1.25 4 + 3 2 1 0 + 0.2 1.2 + 0.2 + 1.2 + 0.2 = 42 (101010)2 = (42)10 - To octal 100101101  1 st step change into denary = 8 5 3 2 0 1.2 + 1.2 + 1.2 + 1.2 + 1.2 = 256 8 + 32 + + 4 + 1
16 =(301)10  2 nd step: convert octal to 301 8 61 37 8 5 5 4 (301)10 = (455)8 (100101101) 2 = (455)8 - To hexadecimal 110111011011 1 st step = 11 10 8 7 6 4 3 1 0 1.2 + 1.2 + 1.2 + 1.2 + 1.2 + 1.2 + 1.2 + 1.2 + 1.2 = 2048+ 1024 + 256 + 158 + + + 64 + 16 + 8 2 1 10 = (3547) 2 nd step 3547 16 384 221 16 27 61 1 1 1 (3547)10 = (CC A) 16 (110111011011) 2 = (CC A) 16 3. Convert into binary and display the answ er normalized in exponential form 247 1 123 1 61 1 1 30 1 15 7 1 3 1 1 1 0 1 (247)10 = (11110111) 2 = 1111011 2 0. x normalized exponential form Q uestion 3. Integer and Floating point – arithmetic? 1. Floating point – Addition a. (0.1011 x 5 ) 2 + (0.1001 2 5 x ) = (0.1011 1001) 2 5 + 0. x = 1.0100 5 x 2 = 0.10100 6 x 2 b. (0.1001 x 3 ) 2 + (0.1110 2 5 x ) = (0.001001 2 5 + x ) (0.1110 2 5 x ) 5 = (0.001001 + 0.111000) 2 x = 1.000001 2 5 x = 0.1000 2 6 x (here have truncation) (0.1000001 2 6 x )
17 2. Floating point – subtraction a. (0.1110 x 7 ) (0.1100 2 7 ) 2 – x 7 = 0.0010 2 x 10 x 5 = 0. 2 b. (0.1001 x 8 ) ( 2 – 0.1000 2 5 x ) = (0.1001 2 – 0.0001 2 8 8 x ) ( x ) 8 = 0.1000 2 x 3. Floating point ultiplication – m a. (0.1010 x 3 ) (0.1100 x 3 ) 2 x 2 6 = (0.1010 0.1100) 2 x x = 0.01111 2 6 x = 0.1111 2 5 x b. (0.11110 2 3 ) x x ((0.01011) 2 4 x ) 7 = (0.11110 0. x 01011) 2 x = 0.001111 x 7 2 = 0.1111 x 5 2 4. Floating point – division. a. (0.11010 2 6 ) : (0.001 2 6 ) x x = (0.11010 2 6 ) x 3 ) x : (1 2 = 0.1101 2 6 2 3 x : 1x = 0.1101 2 3 x b. (0.110111 2 6 ) (0.1001 2 4 ) x : x 2 = (0.110111 : 0.1001) 2 x = : 1001) x 2 (1101.11 2 = 1.100001 x 2 2 = 0.1100001 x 3 2 Chapter TYP E S 3: OF INSTR U C TI O N N D D D R E S SI N G. A A Q uestion 1. Types instructions of used C S ? in 1. Arithmetic instructions. Arithmetic instructions include directives to the co m p uters to perform additions, subtraction, m ultiplications, divisions and exponentiations. 2. Input/ output instructions. They direct the co m p uter to read data values from the specified input devices into the ain m store for processing. They also include instructions write to the contents m e m ory of locations holding the resultof processing a to specified output device. 3. Decision control instructions. or M o st data processing application will contain situations where alternative calculations procedures or willhave be to executed based on the result of condition tests carried out. 4. Data handling instructions They include the copying the of content one e m ory of m location another setting to or a e m ory m locations an to init ialvalue. Also include the a n a g e m e nt insertion characters m or of into data items Exa m ples of such instructions include branch instructions, jump instruction & stop instruction. Q uestion 2. Types addressing? of 1. Direct addressing
18 The operands each a chine of m instructions is used retrieve to the data 2. Indirect addressing The operands used specify is to the e m ory m address which contains the address of the data be to processed p code O – OP CO D E – OPE R A N D OP COD E – OPE R A N D 12345 Data item 12345 Data item ain M storage Direct addressing Indirect addressing 3. Indexed addressing - The m ain applications of this type of addressing technique is to enable to access sequential locations m e m ory of in that are adjacent each to other - Each adjcent m e m ory address has value n+1, where n is the address of the previous location - W h e n the first of the location have been accessed, the next m e m ory location in sequence is accessed by simply increasing the add of the present location 1 by & using accessing it - The starting address of the series of locations is specified in the operand of the instruction - In order to access the next location in sequence, the content of the index register is increased 1 added the by a to opreand address - This is done repeatedly until the last m e m ory location in the series is processed Indexed addressing. OP COD E – OPE R A N D Index Register Data 1 Data 2 Data 3 Data 4 Chapter P R O G R A M M I N G N G U A G E S. 4: LA Q uestion 1. Progra m and level of language? Progra m is group constructions of that is linked together perform to specifictask. It’s necessary co m p uter for a progra m be to written a in “PL” because a m p uter at co
19 progra m is created a by progra ming using sys a analyst’s specification the of job in the hand. 1. M a chine language - M L set bit(0,1) that can performed is the of considered C P U by - Ads  fast  short prog  store s m all m e m ory in - Dis  difficultto understand & reme m b er its code  takes lot of a time progra m ming to  difficultto use 2. Lo w level language - LLL is used dercribe to exactly procedure performance C P U of of at certain time - Features:  Instruction is written natrural English natural language by or  M ore werful and the po so prog is shortest  Need less instruction  Is one one a to relationship between the written instruction and the a chine m instructions  It’sinstruction tend be a chine. to m Itruns O S in - Ads:  Easy write to  Easy understand to  Kno w n the processing data C P U in  Prog writing is shortset - Dis:  M u st m plier be co  The time running of prog is longer than a chine m language 3. High level language - HLL was developed in order further easy the work of to progra m m ers by m a king the progra m ming language ore m procedure oriented - Features:  The statements HLL of are closer natural english other to or natural language  A HLL source progra m u st m be translated into ac hine m code by e a ns a m piler an m of co or interpreter - Ads:  Easy wirte to  Easy understand to  May be used for everybody  Closed natural languages to english language - Dis:  M u st be interpreter by m piler an co or interpreter before processing the m p uter by co  The prog is long
20  The time run to the prog is longer than low level language Q uestion m e 2. So High Level Languages (HLL)? 1. C O B O L: m m o n Co Business Oriented Language - C O B O L is an exetensively used HLL and since around 1960 several versions have appeared - The original intention was that O B O L C should be capable being of co m piled and run on any o d el co m p uter m of - C O B O L is no w m ployed a ny e for m business data processing applications, and a so brief explaination its structure of follows - A C O B O L progra m consists 4 of divisions:  Identifycation division this identif ies the prog  Enviroment division specifies the m p uter be co to used for co m piling and processing  Data division specifies the format and relates these the to to na m e s used the in procedure division  Procedure division m prises co the statements the in source progra m, this is the ain m part a O B O L of C progra m 2. B A SI C: Beginners ALL purpose m b olic Sy Instruction Code - B A SI C is a straightforward HLL intended for use a in timesharing environ me nt this respect in itis particularly beneficialin educational institutions - O n e the of difficult ies with A SI C B is the welter dialects of currently in use - EssentiallyB A SI C consists statements a d e up of of m verbs & variables. The verbs are similar to those C O B O L in but there large them is a to that in effect beco m e the addresses their locations the ain of in m store - A variable m e ust na m be unique and generally consists one a of or few alphabetic characters, purhaps followed a by digit 3. P A S C A L: m e d after famous th na the 17 century French athe m atician m - Itwas expressly designed a as language m ak e to progra m ming ore m systematic and discriplired and these in respects lends itselfto structured progra m ming - Itis wever ore ho m difficultto learn than are O B O L S A SI C C B and is so unliked be to accepted a as language for microco m p uters are geared to B A SI C only Q uestion p erating 3. O Systeim? - Concept of S: O  An S O consists a of suite progra ms, of one which, of the m a ster, kernel exeactive or progra m, remains resident the in m ain store. This progra m controls the other S O progra ms in th suites and between the m they controls the application progra ms  Often the operating system includes various application packages m o n g a its suit of progra ms. such Ex of software include: word processing, electronic ail, networking, m speadsheet, graphics and filehandling - Function O S of  Pricrityassign m e nt: