C / C++ / MFC

register = register ^ 0x02;

Command    |    Cash Drawer 1    |   C code
-----------------------------------------------------------
O 4B8 01   |    Opening          | outp(0x4B8, 0x01);
O 4B8 00   |    Allow to closing | outp(0x4B8, 0x00);

unsigned int curStatus = inp(0x4B8);
curStatus = curStatus & 0x10;  // 0x10 = 0001 000 in binary. Right-most bit is bit0, 4 bits per hexadecimal digit.
if (curStatus == 0)
  printf("Drawer is open\n");  // bit 4 wasn't set
else
  printf("Drawer is closed\n");

#include <windows.h>
#include <iostream>
using namespace std;

int main()
{
    HANDLE hIn;
    HANDLE hOut;
    COORD KeyWhere;
    COORD MouseWhere;
    COORD EndWhere;
    bool Continue = TRUE;
    int KeyEvents = 0;
    int MouseEvents = 0;
    INPUT_RECORD InRec;
    DWORD NumRead;

    hIn = GetStdHandle(STD_INPUT_HANDLE);
    hOut = GetStdHandle(STD_OUTPUT_HANDLE);

    cout << "Key Events   : " << endl;
    cout << "Mouse Events : " << flush;

    KeyWhere.X = 15;
    KeyWhere.Y = 0;
    MouseWhere.X = 15;
    MouseWhere.Y = 1;
    EndWhere.X = 0;
    EndWhere.Y = 3;

    while (Continue)
    {
        ReadConsoleInput(hIn,
                         &InRec,
                         1,
                         &NumRead);

        switch (InRec.EventType)
        {
        case KEY_EVENT:
            ++KeyEvents;
            SetConsoleCursorPosition(hOut,
                                     KeyWhere);
            cout << KeyEvents << flush;
            if (InRec.Event.KeyEvent.uChar.AsciiChar == 'x')
            {
                SetConsoleCursorPosition(hOut,
                                         EndWhere);
                cout << "Exiting..." << endl;
                Continue = FALSE;
            }
            break;

        case MOUSE_EVENT:
            ++MouseEvents;
            SetConsoleCursorPosition(hOut,
                                     MouseWhere);
            cout << MouseEvents << flush;
            break;
        }
    }

    return 0;
}

include <fstream.h>
#include <conio.h>
#include <dos.h>
#include <stdlib.h>
#include <alloc.h>

const ress=0xb;

unsigned hspd,vspd,thv,button,mouse_x,mouse_y;
int dirx,diry,dir_x,dir_y,trshold;
unsigned char mousestep;



void initmouse(void)
{
  asm{
       mov ax,1h
       int 33h

     }
}

void hidemouse(void)
{
  asm{
       mov ax,2h
       int 33h

     }
}


void getmousepos(void)
{
  asm{
	mov ax,3h
	int 33h
	mov button,bx
	mov mouse_x,cx
	mov mouse_y,dx
     }
}


void getmousedirection(void)
{
  asm{
	mov ax,ress
	int 33h
	mov trshold,bx
	mov dirx,cx
	mov diry,dx
     }
}


void getmousespeed(void)
{
  asm{
	mov ax,1bh
	int 33h
	mov bx,hspd
	mov cx,vspd
	mov dx,thv
     }
}