jayron

Unlike DOS, which works under Real mode of processor, Windows works under protected mode of the processor. In protected mode the registers are 32-bit long and are often known as extended registers For example, corresponding to the AX, BX, CX, DX, IP registers of real mode, there exist 32-bit registers called EAX, EBX, ECX, EDX and EIP under protectedAlso under protected mode interrupt handling is a little different. The interrupt vector table is no longer kept at a low address space. Instead it is replaced by another table Interrupt Descriptor Table (IDT) which is kept anywhere in physical memory. A dedicated register called IDTR holds the address of the IDT. While booting Windows constructs the table in available physical memory and stores its address in the IDTR register via a special instruction called SIDT (Store IDT). Windows fills the IDT with addresses of various kernel routines.

Well my view is that, no wonder google is the best search engine ever but Microsoft is Microsoft. What has google done in all these years? Google was just any other search engine. The only thing that kept them ahead is the their website is extremely fast and reason being that they havent put crap on their website like yahoo has. Yahoo! was no wonder the best some years before, but thing have changed because yahoo is slow and they no more just search engine company. I remmember is used to know yahoo as a search engine. And if i share my personal experience, the only reason why i dont use yahoo search engine any more is that the website is real slow and they have a lot of unwanted stuff on their homepage in addition to seach engine.All i wanna say is that Google has Changed nothing. It is just an ordinary search engine who has GROWN in real sense. Now there is no information on the internet which is not available on google and since google progressed in their search engine technology they came up with new services like gmail, picasa, Google Earth etc. But are they up with anything new??Gmail is 2GB and fast. If you search on the net, you can find some email providers providing more than 10GB of storage.If we take Google earth, there are other softwares also similar to it. One is from NASA, well i dont remmember the name correctly.This shows that google is not up with something new. They have all the services.Now lets take Microsoft.We all know that if Microsoft would have focused on the Internet they would have gone far ahead of Google. I think they are the best. Do you think google can really make something like Windows XP or VISTA which have changed the whole world. More than 90% of this world uses Microsoft Operating Systems. Windows is simply the best (except in the case where you wanna do some hacking and all). Though Linux is more Powerfull but it aint as easy to use. Microsoft has changed the dimension of Operating Systems. They have changed something like DOS to WINDOWS and dont you people remmember, they were the first company to provide free email called HOTMAIL. And in those days Microsoft was thought of somethin like we think of Google Today. But things change with time. Microsoft didnt focus only on Internet. They focused in software technology and dominated it. They have the best products and technology around.

I have something to say. There is nothing in this earth like earning money on the internet for free or for just reading some mails or whatever. Why would they pay you. Why would they waste their money on you. They just want to earn money through you. They make you click on links and earn money. Its they who earn the money not you. They earn a lot of money. But you just waste your bandwidth on those website. Please dont go for any of these games or online mail reading programmes for which you get to earn money. They simply dont pay you.

Google is simply the best. I have been using it now for a very long time and according to one of the users google is likely to launch an email hosting service. well, i would really appreciate if google provides this service free. I would have used my domain with it. Well i believe google is one of the best email services around. Google has a lot of products except Gmail like adsense.GOOOGLE ROCKS

Hey, i have been using this overture tool for a long time. And all i have got to say is that it is useless. Most of the ads are outdated. It doesnt help. Moreover, implementing those highest paying keywords dont help.

Memory is your computer system?s primary workspace. It works in tandem with the CPU, to store data, programs and processed information that can then be made immediately and directly accessible to the CPU or to other system devices. Computer memory also determines the size and number of programs that can be run simultaneously, and help to optimize the capabilities of increasing powerful microprocessors.The memory is organized into bytes, each byte capable of storing one character of information. Each byte of memory has an address or location number which uniquely identifies it. The size of the memory is measured either in kilobytes (kb), megabytes (mb), gigabytes (gb) or terabytes (tb). Following the conversions could come in handy at a later stage:Memory could be of two types: RAM (Random Access Memory) or ROM (Read only Memory). Out of these, RAM is used for holding data, instructions and results.The RAM has two important characteristics:1. Data Stored in it can be accessed at random (without need to access all locations before it is sequentially).2. This memory is volatile. It means it contents are lost on switching off the computer. Contrast this to other storage media such as disks, tapes, and CDs that retain data even without power.There are many different kinds of RAMs, each with its own feature and benefits. The two popular varieties are Static (SRAM) and DRAM (Dynamic Ram). The DRAM is called ?dynamic? RAM because it must be refreshed or re-energized hundreds of times each second in order to retain data in its memory cells. Unlike this, SRAM does not need to be constantly refreshed.DRAM costs less and is physically smaller in size, so it is preferred for use in computer?s main memory. Cache is a small block of high-speed memory (usually SRAM) located in the CPU chip. It is used to store frequently requested data and instructions. When the processor needs data, it will check in high-speed cache first to see if the data is there. If not, then the processor will retrieve data from slower main memory. Think of your home refrigerator as a ?cache? for groceries. Now think of food inside of that as data. Instead of going to the grocery store (main memory) every time you get hungry, you first go to the refrigerator (cache) first to see if the food you want is there, If it is, then you?ve saved a lot of time. If not, then you have to spend the extra time to get it from the store.

I have written this simple description of strings in case you cannot understand the one given at the begining. The way a group of integers can be stored in an integer array, similarly a group of characters can be stored in a character array. Character arrays are many a time also called strings. Many languages internally treat strings, but sometimes conceal this fact from the programmer. Character arrays or strings are used by [programming languages to manipulate text such as words and sentences. A string constant is a one-dimensional array of characters teminated by null (\0). For example, char name[] = {H,A,E,S,L,E,R,\0};Each character in the array occupies one byte of memory and the last character is always \0. What character is this? It looks like two characters, but it is actually only one character, with the \ indicating that what follows it is something special. \0 is called null character. Note that \0 and 0 are not same. ASCII value of \0 is 0, Whereas ASCII value of 0 is 48.The elements of the character array are stored in contiguous memory locations. The terminal null (\0 is important, because it is the only way the functions that work with string can know where the string ends. In fact, a string not terminated by a \0 is not really a string, but merely a collection of characters. C concedes the fact that you would use strings very often and hence provides a shortcut for initializing strings. For example, the string used above can also be initialized as, char name[] = HEASLER;Note that, in this declaration \0 is not necessary. C inserts the null character automatically.

The first graphic card, introduced in August of 1981 by IBM, was Monochrome Display Adapter (MDA). The monitors that used these cards were typically text-only with green, amber or white text on a black background.Color for IBM-compatible computers appeared on the scene with the 4-color Hercules Graphics Card (HGC), followed by the 8-color Color Graphics Card (CGA) and 16-color Enhanced Graphics Adapter (EGA).When IBM introduced the Video Graphics Array (VGA) in 1987, a new graphics standard came into being. A VGA display could support up to 256 colors (out of a possible 2,62,144 colors) at resolutions up to 720x400. Perhaps the most interesting difference between VGA and the preceding formats is the VGA was analog, whereas displays had been digital up to that point. Why were displays moved from digital to analog when most other electronic systems like compact disk player, newer VCRs and camcorders use digital picture storage? The answer is color. A digital display generates different colors by using the red, green and blue electron beams. In addition an intensity signal is used to display each color at one of the two intensity levels. This gives rise to a capability to generate 16 colors (24).I will write more on this soon

1: The disk bootstrap Program uses the boot parameters to find the location of the root directory and then loads the file IO.SYS from the root directory into memory. As soon as IO.SYS is loaded the Disk Bootstrap Program is wiped out from memory.2: IO.SYS consists of two modules: Disk BIOS and SYSINIT. The SYSINIT module loads the file MSDOS.SYS from disk into memory and passes control to it.3: MSDOS.SYS builds some internal data structures and work areas and then returns then returns the control to SYSINIT.4: SYSINIT loads a file CONFIG.SYS file from root directory of the floppy. The optional file can contain a variety of commands that enable the user to customize the working environment. For instance the user may specify the number of disk buffers, the maximum number of files that can be opened, etc. If it is found, the entire CONFIG.SYS file is loaded into memory and each command in it is executed one line at a time.5: SYSINIT then loads Resident Portion of the file COMMAND.COM into memory. Once Resident Portion is loaded the SYSINIT module is discarded from memory and control is handed over the Resident Portion.6: The Resident Portion of COMMAND.COM loads the Transient Portion of COMMAND.COM into high end of memory. High end here means the top of base memory. The high end would vary from computer to computer since different computers are likely to have different base memory sizes. The Resident Portion figures out the high end from the base memory size stored at locations 0x413, 0x414 during RAM test.The Transient Portion of COMMAND.COM executes the file AUTOEXEC.BAT, if it is present in the root directory.7: The Transient Portion of COMMAND.COM finally displays the C> prompt.

The operations that take place when a hardware interrupt occurs are as follows:1.A special chip called Interrupt Controller chip receives the interrupt signal.2.The Interrupt Controller chip notifies the microprocessor that an interrupt has occurred.3.To keep track of what microprocessor was doing before it was interrupted, it saves the contents of registers CS, IP and Flags in stack.4.The microprocessor retrieves the number of the interrupt from the Interrupt Controller chip.5.Having found out the interrupt number, it multiplies this number by four (since each address in IVT is 4 bytes long), then goes to the Interrupt Vector Table (IVT) and finds out the address of the corresponding ISR.6.Once the ISR has completed it execution it issues an IRET instruction. As a result, the microprocessor pops the values that were earlier pushed onto the stack, back into CS, IP and Flags registers. From the values in CS:IP microprocessor comes to know which activity it was performing before the interrupt occurred.7.Microprocessor now resumes its interrupted activity.

Ports are used to connect external devices to the computer. There exist several types of ports like serial port, parallel port, USB port, AGP port. As the name suggests, the serial port transfers data serially a bit at a time. As a result, the serial port needs only wire to transmit 8 bits. The disadvantage is that it takes 8 times longer to transmit a byte. Also, it is necessary to send a start bit before each byte of data, a stop bit after the byte to mark the end of byte and a parity bit to help check the integrity of data. Serial ports come in the form of 9-pin or 25-pin male connector. Serial ports are often known as communication ports or RS232C ports. They are typically used to connect devices like mouse and modem.Parallel ports can send or receive a byte (8-bit) at a time. Unlike the serial port, these 8-bits are transmitted parallel to each other. Parallel ports come in the form of 25-pin female connector. Parallel ports are popularly used to connect printer, scanner, CD writer, zip drive, external hard disk drive, tape backup drive, etc.To spare the user botheration of 8-pin, 25-pin, male, female connectors, the USB has been designed. It gives you a single, standardized, easy-to-use way to connect up to 127 devices to a computer. These devices include printers, scanners, mice, joystick, digital camera, web cameras, speakers, telephones, zip drives, network connections, scientific data acquisition devices, etc.The AGP (Accelerated Graphics Port) port is used to connect to graphic card that provides high-speed video performance typically required in games and other multimedia applications.

Array Declaration To begin with, like other variables an array needs to be declared so that the compiler will know what kind of an array and how large an array we want. An example of declaration is: int marks[30];Here int specifies the type of variable, just as it does with ordinary variables and the word 'mark' specifies the name of the variable. the [30] however is something to stress on. The number 30 tells how many elements of the type int will be in our array. This number is often called the 'dimension' of the array. The brackets ( [] ) tells the compiler that we are dealing with an array. Accessing Elements of an Array Once an array is declared, let us see how individual elements in the array can be referred. This is done with subscript, the number in the brackets following the array name. This number specifies the elements position in the array. All the array elements are numbered, starting with 0. Thus marks[2] is not the second element of the array, but the third. In our program we are using variable I as a subscript to refer to various elements of the array. This variable can take different values and hence can refer to the different elements in the array in turn.. This ability to use variables as subscripts is what makes arrays so useful. Entering Data into an Array Here is the section of code that places data into an array: for(i=0;i<=29;i++) { printf(\nEnter Marks); scanf(%d,&marks[i]); } The for loop cause the process of asking for and receiving a students marks from the user to be repeated 30 times. The first time through the loop, I has a value 0, so the scanf() statement will cause the value type to be stored in the array element marks[0], the first element of the array. The process will be repeated until I becomes 29. This is the last time though the loop, which is a good thing, because there is no array element like marks[30]. In the scanf() statement, we have used the address of operator (&) on the element marks of the array. In so doing, we are passing the address of this particular array element to the scanf() function, rather than its value, which is what scanf() requires.

C programming provides a capability that enables a user to design a set of similar data types, called Arrays. For understanding the arrays properly, let us consider the following program main(){int x;j=5j=10;printf("\nj= %d",x);}No doubt, this program will print the value of j as 10. This is because when a value 10 is assigned to j, the earlier value of j, i.e. 5, is lost. Thus, ordinary variables are capable of holding only one value at a time. However, there are situations in which we would want to store more than one value at a time in a single variable. For example, suppose we wish to arrange the percentage marks obtained by 100 students in ascending order. In such case we have two options to store these marks in memory. 1) Construct 100 variables to store percentage marks obtained by 10 differ students, i.e. each variable containing one student;s marks. 2)Construct one variable (called Array or subscripted variable) capable of storing or holding all the hundred values. Obviously, the second alternative is better. A simple reason for this is, it would be much easier to handle one variable than handling 100 different variables. Moreover, there are certain logics that cannot be dealt without the use of an array. An array is a collective name given given to a group of 'similar quantities'. These similar quantities could be percentage marks of 100 students, or salaries of 300 employees, or age of 500 employess. What is important is that the quantity must be 'similar'. Each member in the group is referred to by its position in the group. For example, assume the following group of numbers which represent percentage marks obtained by five students. perc = {48, 88, 34, 23, 96}; If we want to refer to the second number of the group, the usual notation used is perc(2) similarly, the fourth number of the group is referred as perc(4). However, in C, the fourth number is referred as perc[3]. This is because in C the counting of elements begin with 0 and not with 1. Thus, in this example perc[3] refers to 23 and perc[4] refers to 96. In general, the notation would be perc, where, i can take a value 0,1,2,3 or 4, depending on the position of the element being regerred. Here perc is the subscripted variable (array), whereas 1 is its subscirpt. Thus, an array is a collection of similar elements. These similar elements could be all ints, or all floats, or all chars, etc. Usually, the array of characters is a called a string, whereas an array of ints or floats is simply called an array. Remember that all elements of any given array must be the same type, i.e. we cannot have an array of 10 numbers, of which 5 are ints and 5 are floats.

hi fsd, i agree with the fact that you should learn C programming before going for C++. C++ is an improvement over C. So it would be better to learn C before C++, as you will get to know about the basics. Also I think you should get a good book on C++ and learn classes yourself by reading from the book. I dont think anyone will take any pains to teach you the basics of classes. You can ask for tutorials when you have atleast some knowledge. Tutorials should be taken when you encounter a problem while programming or when you want to learn some advanced things from someones experience.I would recommend you to first get some popular C++ programming and then learn all the syntaxes and knowledge about Class in C++ and then if you encounter any problems while programming you may ask for a tutorial. Also i would like to recommend you to start learning C if you havent learned much in C++. If you have already gone too deep into C++ and have a clear concept about everything then you may not need to take up C. If you need any tutorial for C programming then i am ready to help

Hi, i agree with all of you who say that there is no problem if students get pirated copies of all these expensive softwares like photoshop, dreamweaver, flash, norton etc. And i read someone has written that the companies know that the students get pirated copies of their softwares and they have officially announced that they have no problem. When the company has no probkem why do some people have problem with that. And also someone said that it represents your character and you can even betray your friends and family if you get pirated copies of all the softwares. But i have a different view. Just because some students dont have so much money to spend on all these expensive softwares they get the pirated versions and after all they are gonna be our future software programmers, graphics designers and other computer programmers. They need all these softwares to learn them, and master them. They are infact our Future. And they ofcourse dont earn so much.. So i think if the students get pirated copies of these softwares there is nothing wrong in it.And it doesnt reflect ones character at all