Device,Driver,Basics, computer Device Driver Basics

Gone are those times when the companies and the organisations didn't need a hi-tech system to handle them. Owing to the considerable increase in the business sector and thus, an enormous increase in the complexity of the organisational struc ----------------------------------------------------------Permission is granted for the below article to forward,reprint, distribute, use for ezine, newsletter, website,offer as free bonus or part of a product for sale as longas no changes a

----------------------------------------------------------Permission is granted for the below article to forward,reprint, distribute, use for ezine, newsletter, website,offer as free bonus or part of a product for sale as longas no changes are made and the byline, copyright, and theresource box below is included. ----------------------------------------------------------Device Driver BasicsBy Stephen BucaroMost people understand that the "hardware" part of theircomputer is the real physical parts, like the keyboard,mouse, modem, hard drive and so on. They understand thatthe "software" is computer bits stored on the hard drive,CD-ROM, or other storage media. But most people are alittle hazy about exactly what a "driver" is.In this article, I'm going to reveal in plain English whata driver is, why we need drivers, and exactly where thedrivers are hiding. To give you a basic understanding, I'mgoing to go back, way back, to the early days of computers.The Early DaysThe year is 1981 and the world is in the midst of a severeresession. IBM's main frame business has slowed and thecompany is losing money. Up until now they had beenlaughing at the array of microcomputers on the market:Atari, Commodore, sinclair. Toys really, mostly used toplay computer games.The problem was, these "toys" were selling like hot cakes.IBM had to get into that market and get into it fast. Theydidn't have time to design and build a computer completeenough to compete in the market, so they built an "opensystem". They used commonly available electronic componentsand they published every design detail (including the code),and they even provided plug in slots so that others couldbuild components for their computer.And people did provide components for the IBM PC. Theyprovided video cards, memory expansion cards, input-outputport cards, game port cards, hard disk interface cards, andmuch more. How were all these various devices able tointerface with the PC's operating system? That's where a"driver" comes in.A hardware device is constructed with various electroniccomponents using various control signals, but the softwareinterface to the operating system is standardized. Adevice's interface to the operating system must follow theinterface specification. A driver is a piece of softwarethat translates the hardware's control signals to signalsthat the operating system expects, and translates signalsfrom the operating system to the hardware's control signals.When the computer is started up, it would look in the"system" directory for files with the extension ".drv" andload them into memory. Specific files like autoexec.bat,config.sys, and win.ini were used to inform the operatingsystem about drivers. Hardware would be configured throughthese files, or through jumpers located on the device itself.The driver specification evolved along with the PC. Todaywhen a PC starts, it executes the program ntdetect.comwhich queries the hardware components and builds theregistery keyHKEY_LOCAL_MACHINEHARDWARESYSTEMCurrentControlSet.This key exists only in memory and is created each time thecomputer boots. If all the drivers are loaded successfully,a copy of the key is saved as ControlSet00X.Under the registery key CurrentControlSet, the subkey"Enum" contains a subkey for each harware device on thecomputer. Each device key contains fields for Hardware ID,Driver ID, Device Parameters, and other configuration data.The 32-bit drivers are files with the extension ".sys" andcan be found in the folder C:/winnt/system32.Driver SigningMicrosoft has been the brunt of much criticism because ofthe poor reliability of the Windows Operating System. Ifeel that much of this criticism is justified. On theother hand, as I described in part 1 of this article, thePC was designed by IBM as an "open" system. Anyone can sella hardware device (or software) for the PC. ShouldMicrosoft be held responsible for the quality from athird-party?As I described in Part 1 of this article, the operatingsystem doesn't interface directly to a hardware device.There is a piece of software called a "driver" thattranslates the hardware's control signals to signals thatthe operating system expects, and translates signals fromoperating system to the hardware's control signals.Obviously, the hardware manufacturer provides the driver.Because the driver works between the operating system andthe hardware, a bug in the driver can cause a seriousproblem. Many of the problems with Windows have come frombugs in third-party drivers that Microsoft had nothing todo with. For this reason, Microsoft created a HardwareQuality Lab to test drivers. A hardware manufacturer cansubmit their driver for testing, and if it is passesrigorous compatibility testing, it receives Microsoft'sdigital signature.You may have received a message during the installation ofa hardware device warning that the driver was not signed.Why would a hardware manufacturer fail to have their drivercertified by Microsoft? The computer hardware market isvery competitive and the manufacturer might want to bringa new product to market before thorough testing can becompleted. Or maybe they don't want to or can't afford topay Microsoft for certification. The question is, shouldyou click on the "Continue" button to install the unsigneddriver?In my experience, I have never been able to trace a problemto an unsigned driver. If it's your home computer and youperformed a back-up recently, go ahead and install theunsigned driver. If it's a computer on a corporate network,you may want to back-out of the installation and see if youcan locate a signed driver first. Many times a manufacturerwill release a product with an unsigned driver, then laterprovide a signed driver as a free download from theirwebsite.If you decide to go ahead and install an unsigned driver,you can always update the driver later. If your computerworks with the unsigned driver, I would not update thedriver. When it comes to updating drivers (or the computersBIOS) I go by the old saying, "if it ain't broke don't fixit".To update a driver, select Start | Settings | Control Paneland double-click on the "System Properties" Utility. In the"System Properties" Utility, select the "Hardware" tab andclick on the "Device Manager" button. In the "DeviceManager" window, right-click on the device in the list andselect "Properties" in the popup menu. In the "Properties"dialog box, select the driver tab and click on the "UpdateDriver..." button.In the "Properties" dialog box driver tab, you may havenoticed the "Roll Back Driver" button. If your computer hasproblems with the new drive, you can click on the "RollBack Driver" button to roll back to the previous the driver.Driver roll back saves only one previous driver, so if youupdate a driver, then update it again, the original driveris gone. If the computer has problems with the new driver,always roll back to the original driver before trying adifferent one. That way you'll always have the originaldriver to roll back to.----------------------------------------------------------Resource Box:Copyright(C) Bucaro TecHelp. To learn how to maintainyour computer and use it more effectively to design a Website and make money on the Web visit bucarotechelp.comTo subscribe to Bucaro TecHelp Newsletter visithttp://bucarotechelp.com/search/000800.asp---------------------------------------------------------- Article Tags: Device Driver, Operating System, Hardware Device, Control Signals, Hardware's Control, Hardware Manufacturer, Unsigned Driver, Roll Back