C Programming Code Examples
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To Implement Recalibrate Command
/* To Implement Recalibrate Command */
#include<conio.h>
#include<stdio.h>
#include<dos.h>
void main()
{
int show;
clrscr();
//Put on the motor
outp(0x3f2,28);
// Check whether the FDC is ready
show=inp(0x3f4); //Read the status of MAIN STATUS REGISTER
show=(show&128);
if(show==128)//Check whether FDC is ready
{
//Input the command parameters
outp(0x3f5,7);//Enter command parameters
delay(200);
outp(0x3f5,0);//Enter Drive No.
delay(300);
}
// Check the status of data register
show=inp(0x3f5);
if(show==0)
printf("Succesfully executed Recalibrate command");
getch();
//Put off the motor
outp(0x3f2,0);
}
The getch() is a predefined non-standard function that is defined in conio.h header file. It is mostly used by the Dev C/C++, MS- DOS's compilers like Turbo C to hold the screen until the user passes a single value to exit from the console screen. It can also be used to read a single byte character or string from the keyboard and then print. It does not hold any parameters. It has no buffer area to store the input character in a program.
Function clrscr() clears the screen and moves the cursor to the upper left-hand corner of the screen. If you are using the GCC compiler, use system function to execute the clear/cls command. clrscr() function is also a non-standard function defined in "conio.h" header. This function is used to clear the console screen. It is often used at the beginning of the program (mostly after variable declaration but not necessarily) so that the console is clear for our output.
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Writes the C string pointed by format to the standard output (stdout). If format includes format specifiers (subsequences beginning with %), the additional arguments following format are formatted and inserted in the resulting string replacing their respective specifiers. printf format string refers to a control parameter used by a class of functions in the input/output libraries of C programming language. The string is written in a simple template language: characters are usually copied literally into the function's output, but format specifiers, which start with a % character, indicate the location and method to translate a piece of data (such as a number) to characters. "printf" is the name of one of the main C output functions, and stands for "print formatted". printf format strings are complementary to scanf format strings, which provide formatted input (parsing). In both cases these provide simple functionality and fixed format compared to more sophisticated and flexible template engines or parsers,
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