// Unfortunately, these two functions work just in real DOS mode.
#define drive_a 0
#define drive_b 1
void lightdrvon(unsigned char drive)
{
 outport(0x3f2, 12 +drive +1 << (4 +drive));
}
void lightdrvoff(unsigned char drive)
{
 outport(0x3f2, 12 +drive);
}

// Keyboard Leds
void scroll_lockon()
{
 pokeb(0x40, 0x17, peekb(0x40, 0x17) | 0x10);
}
void scroll_lockoff()
{
 pokeb(0x40, 0x17, peekb(0x40, 0x17) & 0xef);
}

void num_lockon()
{
 pokeb(0x40, 0x17, peekb(0x40, 0x17) | 0x20);
}
void num_lockoff()
{
 pokeb(0x40, 0x17, peekb(0x40, 0x17) & 0xdf);
}

void caps_lockon()
{
 pokeb(0x40, 0x17, peekb(0x40, 0x17) | 0x40);
}
void caps_lockoff()
{
 pokeb(0x40, 0x17, peekb(0x40, 0x17) & 0xbf);
}

// text mode Cursor
void showcursor()
{
 asm{
  mov ax, 0x100
  mov cx, 0x506
  int 0x10
 }
}
void hidecursor()
{
 asm{
  mov ax, 0x100
  mov cx, 0x2607
  int 0x10
 }
}

// monitor
void screenon()
{
 outport(0x3c4, 1);
 outport(0x3c5, 0x00);
}
void screenoff()
{
 outport(0x3c4, 1);
 outport(0x3c5, inport(0x3c5) | 0x20);
}