/****************************************************************************
 *                        C SAMPLE #4: SAMPLE4.C                            *
 *                                                                          *
 *  This sample will continuously read the digital input port and display   *
 *  the value bit by bit.                                                   *
 *                                                                          *
 ****************************************************************************/

#include <conio.h>
#include <stdio.h>

#define uint unsigned int

void DisplayInfo( void);
uint AskForBaseAddress( uint);

void main()
{
  unsigned int i, BaseAddress = 0x340;

  clrscr();
  DisplayInfo(); // tell the user what to expects
  gotoxy( 1, 5); // set the screen position for AskForBaseAddress()
  BaseAddress = AskForBaseAddress( BaseAddress);
  outp( BaseAddress + 1, 0); // tristate the digital port and set to zero
  outp( BaseAddress, 0x20);  // initialize the control register
  while( !kbhit())           // loop until the user presses a key
  {
    gotoxy( 30, 12);
    for( i = 0; i <= 7; i++)
    {
       if( inp( BaseAddress+1) & ( 0x80 >> i)) printf( " 1");
       else printf( " 0");
    }
  }
  puts( "\n");                        // add some space after our output line
  if( kbhit()) if( !getch()) getch(); // clean up the key buffer
  outp( BaseAddress + 1, 0);          // tristate the digital port
}

void DisplayInfo()
{
  puts( "                             C SAMPLE #4: SAMPLE4.C");
  printf( "\nThis sample will continuously read the digital input port and"
          " display the\n");
  puts( "value bit by bit.");
}

unsigned AskForBaseAddress( unsigned int OldOne)
{
	char msg[7];
	int NewOne = 0, Success = 0, Dummy;
	int AddrInputPosX, AddrInputPosY;

	puts("\nPlease enter the Base Address for your card (in hex)");
	printf("or press ENTER for %X.\n>", OldOne);
	AddrInputPosX = wherex(); AddrInputPosY = wherey();
	do {
		gotoxy(AddrInputPosX, AddrInputPosY);
		clreol();
		msg[0] = 5; msg[1] = 0;
		cgets(msg);
		sscanf(msg + 2, "%x", &NewOne);
		Success = 1;
		Dummy = NewOne;
		if (msg[1] == 0) {
			gotoxy(AddrInputPosX, AddrInputPosY);
			printf("%X", OldOne);
			Success = 1;
			Dummy = OldOne;
		}
	} while(!Success);
	return (Dummy);
} /* end of AskForBaseAddress */