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Code: Select all

byte X1 = 0, Y1 = 0, X2 = 79, Y2 = 24, TextAttr = 7;

enum {Black = 0, Blue, Green, Cyan, Red, Magenta, Brown, LightGray, DarkGray, LightBlue, LightGreen, LightCyan, LightRed, LightMagenta, Yellow, White, Blink = 128};

void ClrScr(void)
{
   _AH = 0x6;
   _AL = 0;
   _BH = TextAttr;
   _CH = Y1;
   _CL = X1;
   _DH = Y2;
   _DL = X2;
   asm int 0x10;
   _AH = 0x2;
   _BH = 0;
   _DH = Y1;
   _DL = X1;
   asm int 0x10;
}

void GotoXY(byte X, byte Y)
{
   _AH = 0x2;
   _BH = 0;
   _DH = Y1 + Y - 1;
   _DL = X1 + X - 1;
   asm int 0x10;
}

byte ReadKey(void)
{
   _AH = 0x0;
   asm int 0x16;
   return _AL;
}

void TextBackground(byte Color)
{
   TextAttr &= 0x0F;
   TextAttr |= Color << 4;
}

void TextColor(byte Color)
{
   TextAttr &= 0xF0;
   TextAttr |= Color;
}

byte WhereX(void)
{
   _AH = 0x3;
   _BH = 0;
   asm int 0x10;
   return _DL - X1 + 1;
}
byte WhereY(void)
{
   _AH = 0x3;
   _BH = 0;
   asm int 0x10;
   return _DH - Y1 + 1;
}

void Window(byte XA, byte YA, byte XB, byte YB)
{
   X1 = XA - 1;
   Y1 = YA - 1;
   X2 = XB - 1;
   Y2 = YB - 1;
}

Code: Select all

typedef unsigned char byte;
typedef unsigned int  word;

#include <crt.h>

void main(void)
{
   _AH = 0x0; //Set 80x25x16 Text Mode
   _AL = 3;
   asm int 0x10;

   TextBackground(Blue);  //Do something
   TextColor(Cyan);
   Window(1, 1, 80, 1);
   ClrScr();
   Window(1, 25, 80, 25);
   ClrScr();
   TextBackground(Cyan);
   TextColor(Blue);
   Window(1, 2, 80, 24);
   ClrScr();

   while (1);    //stop
}

Code: Select all

#pragma inline //use TASM to compile 32bit opcode

void main(void){ //we don't need an arguments or returned values
//since parsing argument required DOS interrupt

asm{.386 //386 opcode
mov eax,0x123456
//don't forget to add prefix opcode
.286 //286 opcode
}

//and use far instruction to reach address beyond 640KB
unsigned char far *v=(unsigned char far *)0x10000000L;

v[0x123]=0xff;//assign a value 0xff to 0x1000:0x123

}