[CarltonBirch]

I am making a really simple robot from computer components. I need a program that will open and close cd units in a time period of 5 seconds. There will be 2 cd units. So my idea is to make a program that will open the cd unit then keep it opened for 5 sec and then close it. I can sort this out with hardware accessories some electrical timers. But i want to see if i can keep it single with a program. It should run on windows xp platform.

[Ganesh]

I did some googling and it turns out it is possible to write this program in c++ or VB ? so if anyone is willing to help it would be nice!

[ShikhaTan]

I have some basic knowledge of c++ so if there is a good article out there on this i think i would be able to write it. But if someone is willing to write it for me which should take too long i think it would be perfect. As i sad i am on a project to make a robot so i have a lot of work on hardware and really little time.

[SapnaVishwas]

in python using pygame

import pygame.cdrom as cdrom
cdrom.init()
cd = cdrom.CD(0) # 0 = first cdrom device
cd.init()
cd.eject()
cd.quit()
cdrom.quit()

[Amit]

To do it in C++, use CreateFile() and give it the drive letter for the file name. When you have the handle, you can use DeviceIoControl() and use IOCTL_STORAGE_EJECT_MEDIA or IOCTL_STORAGE_LOAD_MEDIA. For a simple timer, you can use GetTickCount(). If you need something better, you can use QueryPerformanceCounter().

CreateFile

http://msdn.microsoft.com/en-us/library/windows/desktop/aa363858%28v=vs.85%29.aspx

DeviceIoControl

http://msdn.microsoft.com/en-us/library/windows/desktop/aa363216%28v=vs.85%29.aspx

GetTickCount

http://msdn.microsoft.com/en-us/library/windows/desktop/ms724408%28v=vs.85%29.aspx

QueryPerformanceCounter

http://msdn.microsoft.com/en-us/library/windows/desktop/ms644904%28v=vs.85%29.aspx

Below is a simple program that will open and close all your CD trays.

#include 
#include 

#define MAXBUFFER 512

int _tmain()
{
   HANDLE hDrive;
   TCHAR drives[MAXBUFFER];

   if (GetLogicalDriveStrings(MAXBUFFER - 1, drives))
   {
      DWORD temp;
      TCHAR * ptrDrives = drives;
      TCHAR strDrive[] = TEXT("\\\\.\\ :");

      do
      {
         if (GetDriveType(ptrDrives) == DRIVE_CDROM)
         {
            *(strDrive + 4) = *ptrDrives;

            hDrive = CreateFile(strDrive, GENERIC_READ, FILE_SHARE_READ | FILE_SHARE_WRITE, NULL, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL);

            if (hDrive == INVALID_HANDLE_VALUE)
               break;

            if (!DeviceIoControl(hDrive, IOCTL_STORAGE_EJECT_MEDIA, NULL, 0, NULL, 0, &temp, NULL))
            {
               CloseHandle(hDrive);
               break;
            }

            if (!DeviceIoControl(hDrive, IOCTL_STORAGE_LOAD_MEDIA, NULL, 0, NULL, 0, &temp, NULL))
            {
               CloseHandle(hDrive);
               break;
            }

            CloseHandle(hDrive);
         }
         while (*ptrDrives++);
      } while (*ptrDrives);
   }

   return 0;
}

[SapnaVishwas]

Here it is. It is done in Visual studio. Works perfectly except the first cycle. ( it opens and closes the first driver without delay). But after that it just does what is suppose to do.

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Diagnostics;
using System.Windows.Forms;

namespace WindowsFormsApplication1
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        [System.Runtime.InteropServices.DllImport("winmm.dll", EntryPoint = "mciSendStringA")]
        public static extern void mciSendStringA(string lpstrCommand, string lpstrReturnString, long uReturnLength, long hwndCallback);

       

        string rt = "";


        private void button1_Click(object sender, EventArgs e)
        {           
            timer1.Interval = 1000 * 5; //timer to open first and close second
            timer1.Enabled = true;
            timer1.Start();
            timer2.Interval = 1000 * 5; //revers timer
            timer2.Enabled = true;
            mciSendStringA("open D: type CDAudio alias driveD", rt, 127, 0); //defining driver
            mciSendStringA("open E: type CDAudio alias driveE", rt, 127, 0);
        }

        private void button2_Click(object sender, EventArgs e)
        {           
            //test button

            mciSendStringA("set driveF door open", rt, 127, 0);
            MessageBox.Show("Radi li");
        }       

       
        private void timer1_Tick(object sender, EventArgs e)
        {
            //open first close second
            mciSendStringA("set driveE door closed", rt, 127, 0);
            mciSendStringA("set driveD door open", rt, 127, 0);
            //MessageBox.Show("start");
            timer1.Stop();
            timer2.Start();
        }

        private void timer2_Tick(object sender, EventArgs e)
        {
            //open second close first
            mciSendStringA("set driveD door closed", rt, 127, 0);
            mciSendStringA("set driveE door open", rt, 127, 0);
            //MessageBox.Show("stop");
            timer2.Stop();
            timer1.Start();
        }

    }
}