Device Driver Basics

Device Driver Basics

by: Stephen Bucaro

Most people understand that the กhardwareก part of their computer is the real physical parts, like the keyboard, mouse, modem, hard drive and so on. They understand that the กsoftwareก is computer bits stored on the hard drive, CDROM, or other storage media. But most people are a little hazy about exactly what a กdriverก is.

In this article, Iกm going to reveal in plain English what a driver is, why we need drivers, and exactly where the drivers are hiding. To give you a basic understanding, Iกm going to go back, way back, to the early days of computers.

The Early Days

The year is 1981 and the world is in the midst of a severe resession. IBMกs main frame business has slowed and the company is losing money. Up until now they had been laughing at the array of microcomputers on the market: Atari, Commodore, sinclair. Toys really, mostly used to play computer games.

The problem was, these ‘toysก were selling like hot cakes. IBM had to get into that market and get into it fast. They didn’t have time to design and build a computer complete enough to compete in the market, so they built an กopen systemก. They used commonly available electronic components and they published every design detail (including the code), and they even provided plug in slots so that others could build components for their computer.

And people did provide components for the IBM PC. They provided video cards, memory expansion cards, inputoutput port cards, game port cards, hard disk interface cards, and much more. How were all these various devices able to interface with the PCกs operating system? Thatกs where a กdriverก comes in.

A hardware device is constructed with various electronic components using various control signals, but the software interface to the operating system is standardized. A deviceกs interface to the operating system must follow the interface specification. A driver is a piece of software that translates the hardwareกs control signals to signals that the operating system expects, and translates signals from the operating system to the hardwareกs control signals.

When the computer is started up, it would look in the กsystemก directory for files with the extension ก.drvก and load them into memory. Specific files like autoexec.bat, config.sys, and win.ini were used to inform the operating system about drivers. Hardware would be configured through these files, or through jumpers located on the device itself.

The driver specification evolved along with the PC. Today when a PC starts, it executes the program ntdetect.com which queries the hardware components and builds the registery key HKEY_LOCAL_MACHINE\HARDWARE\SYSTEM\CurrentControlSet. This key exists only in memory and is created each time the computer boots. If all the drivers are loaded successfully, a copy of the key is saved as ControlSet00X.

Under the registery key CurrentControlSet, the subkey กEnumก contains a subkey for each harware device on the computer. Each device key contains fields for Hardware ID, Driver ID, Device Parameters, and other configuration data. The 32bit drivers are files with the extension ก.sysก and can be found in the folder C:/winnt/system32.

Driver Signing

Microsoft has been the brunt of much criticism because of the poor reliability of the Windows Operating System. I feel that much of this criticism is justified. On the other hand, as I described in part 1 of this article, the PC was designed by IBM as an กopenก system. Anyone can sell a hardware device (or software) for the PC. Should Microsoft be held responsible for the quality from a thirdparty?

As I described in Part 1 of this article, the operating system doesn’t interface directly to a hardware device. There is a piece of software called a กdriverก that translates the hardwareกs control signals to signals that the operating system expects, and translates signals from operating system to the hardwareกs control signals. Obviously, the hardware manufacturer provides the driver.

Because the driver works between the operating system and the hardware, a bug in the driver can cause a serious problem. Many of the problems with Windows have come from bugs in thirdparty drivers that Microsoft had nothing to do with. For this reason, Microsoft created a Hardware Quality Lab to test drivers. A hardware manufacturer can submit their driver for testing, and if it is passes rigorous compatibility testing, it receives Microsoftกs digital signature.

You may have received a message during the installation of a hardware device warning that the driver was not signed. Why would a hardware manufacturer fail to have their driver certified by Microsoft? The computer hardware market is very competitive and the manufacturer might want to bring a new product to market before thorough testing can be completed. Or maybe they don’t want to or can’t afford to pay Microsoft for certification. The question is, should you click on the กContinueก button to install the unsigned driver?

In my experience, I have never been able to trace a problem to an unsigned driver. If itกs your home computer and you performed a backup recently, go ahead and install the unsigned driver. If itกs a computer on a corporate network, you may want to backout of the installation and see if you can locate a signed driver first. Many times a manufacturer will release a product with an unsigned driver, then later provide a signed driver as a free download from their website.

If you decide to go ahead and install an unsigned driver, you can always update the driver later. If your computer works with the unsigned driver, I would not update the driver. When it comes to updating drivers (or the computers BIOS) I go by the old saying, กif it ain’t broke don’t fix itก.

To update a driver, select Start | Settings | Control Panel and doubleclick on the กSystem Propertiesก Utility. In the กSystem Propertiesก Utility, select the กHardwareก tab and click on the กDevice Managerก button. In the กDevice Managerก window, rightclick on the device in the list and select กPropertiesก in the popup menu. In the กPropertiesก dialog box, select the driver tab and click on the กUpdate Driver…ก button.

In the กPropertiesก dialog box driver tab, you may have noticed the กRoll Back Driverก button. If your computer has problems with the new drive, you can click on the กRoll Back Driverก button to roll back to the previous the driver. Driver roll back saves only one previous driver, so if you update a driver, then update it again, the original driver is gone. If the computer has problems with the new driver, always roll back to the original driver before trying a different one. That way youกll always have the original driver to roll back to.

Copyright(C) Bucaro TecHelp.

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About The Author

Stephen Bucaro

To learn how to maintain your computer and use it more effectively to design a Web site and make money on the Web visit bucarotechelp.com To subscribe to Bucaro TecHelp Newsletter visit http://bucarotechelp.com/search/000800.asp

This article was posted on September 22, 2004

by Stephen Bucaro

PC owners the largest criminal gang ever?

PC owners the largest criminal gang ever?

by: Jamie Plenderleith

The year is 1981. IBM has just released the Personal Computer; a low cost machine it hopes will create a winning brand. Several models are produced in quick succession accompanied by an ad campaign featuring a Charlie Chaplin figure. The message is clear: It’s cheap and it’s cheerful.

The growth vector for the product turns out to be a software application called a spreadsheet. Its many early forms VisiCalc, Multiplan, Lotus 123, along with WordStar wordprocessing and of course games all help drive hardware sales.

Nobody seems to question the rapid and promiscuous spread of these programs by copying onto 5.25ข floppy disks and passing them from person to person.

That was then. This is now. Harsh fines and jail sentences are threatened to anyone involved in doing what came naturally back in the early ‘80s. It’s a Very Bad Thing to copy software without having a license to do so. They say ‘this stuff is ours, we want to be paid for it’, and of course they’re right.

But here is a problem. Software’s binary information is a kind of digital DNA, always wanting to replicate. It’s what has made and sustained the digital revolution. When transmitting information, whether from one disk to another or over the Internet, errors can be corrected, faint signals regenerated as new, and even lost portions of messages recreated. This is the essence of the digital world, and replication is its big trick.

One of the things most of us did with our first computer was to copy something. In our early PC vocabulary COPY was the most popular word. Doing it was so easy and so immediately rewarding. It did nobody any harm – did it? The user got the software and the manufacturer got their product widely distributed.

But a company has to make money, not just gain market share, and at some point in time a shift occurred. It’s as if the manufacturers decided to play the soccer offside rule and grab the high moral ground at the same time nearly every PC owner in the world was suddenly wrongfooted. And no one after all can disagree with their position. But how will they play catchup on their lost revenues? How can they now make all their customers compliant?

A London analyst who specialises in intellectual rights issues says ‘the paradigm we have at present where the license chases the product doesn’t seem to be an effective mechanism for compliance by itself.ก

In other words trying to push a license into everywhere the software has gone without the ease with which the software got there in the first place will prove difficult. But that’s not all.

An account manager for a hardware firm in the US says กIt can be difficult to keep the licensing nailed down. The hardware changes, the software moves on, departments, even companies, merge. The picture is always changingก

Demand has always fuelled innovation in Information Technology. Fluid, dynamic, competitive, the elements of IT constantly move. Suppliers apply different strategies at different times for different reasons: Market share, volume shipments, profit. Licensing is a big weapon in their arsenal. Then new technologies emerge, legislation changes, big players go bust and others are created. It’s hard to see how a static and legalistic document can cover all this.

There are also the licensing arrangements that software manufacturers employ. Licenses may be priced according to whether they are academic, charity, large volume, product upgrade, competitive upgrade, client server, thinclient, or one of several other types. On top of that there are the popular service addons of maintenance and technical support.

Of course if we all started afresh that would make things easier. But as that’s impossible we must do two things; look at new software in terms of correct quantity and correct type of license. That’s the easy part. The not so easy part is to look at what your company already has and see what licenses, if any, are missing or incorrect.

‘The biggest criminal gang in history’ is about to be disbanded.

©2003 Jamie Plenderleith

Microsoft Certified Licensing Specialist

Chief Developer Whaddayagot Pro Asset Management Suite

About The Author

Jamie is a software design engineer with Everyman Technologies of Dublin Ireland. He attends Trinity College Dublin part time and is a SciFi fan.

[email protected]

This article was posted on March 27, 2003

by Jamie Plenderleith

Burning Bridges is Bad, But Firewalls are Good

Burning Bridges is Bad, But Firewalls are Good

by: Heather Wallace

When you signed up for that ultrafast DSL or Cable connection there was probably one very important piece of information that your ISP failed to mention. By accessing the Internet via a highspeed connection, you have tremendously increased your chances of being victimized by a computer hacker.

Dialup may not have seemed like it could have held any advantages, but it actually did have one upside. It is much less prone to hacking. Every time you dialedin your computer was assigned a new IP address. That unique IP address made you a moving target that was more difficult for hackers to hit.

With a highspeed connection you are assigned a static IP address (it never changes). So, your computer went from being a moving target to staying still with a bullseye pasted on the side. That, coupled with the fact that with a highspeed connection your computer is always online, are ideal conditions for a potential hacker attack. That seemingly beneficial alwayson connection gives hackers a 24/7 open invitation to try and hack your system. Once inside they can access personal or financial details, compromise your computerกs operating system, or unleash a virus, worm, or spyware.

Which Firewall is Right For You?

Now that you know how vital a firewall is to the protection of your PC you have to decide which firewall is right for you. Software or hardware.

A software firewall is designed to monitor your computers activity at all times. Think of it as a bodyguard who won’t let anyone into your computer if he doesn’t like the look of them. With a software firewall you may to have to assist in protecting your system. The firewall might alert you to certain activity and ask you if you want to grant or deny permission. Itกs just like the bodyguard that was mentioned before. He needs the okay before telling someone to scram. After you give either the thumbs up or the thumbs down the firewall will take the appropriate action and remember your reply so that you won’t be asked in the future.

If you feel comfortable installing and configuring hardware, then you might want to consider a hardware firewall in the form of a Cable/DSL router. The hardware firewall handles everything on its own without any input from you and you also won’t have to read any reports or make any decisions. The firewall handles everything on its own. Installation, however, can be tricky, so this option is definitely more suited to the advanced computer user.

My Firewall is Installed. Now Iกm Safe, Right?

With your new firewall in place you are probably thinking that your computer is impenetrable, right? Well, maybe not. As important to the security of your system as a firewall is, some do have their limits. Most software firewalls won’t scan your system for viruses that can harm your computer and there aren’t any hardware firewalls on the market that offer virus protection. That means that you are still vulnerable to attack.

The best line of defense against viruses that can harm your system is antivirus protection.You can either buy a seperate antivirus program or shop around for a software firewall with antivirus protection builtin. You may never be able to make your computer 100% hackerproof, but the installation of a firewall coupled with antivirus protection will greatly reduce your chances of becoming a hackerกs next victim.

About The Author

Heather Wallace is a writer whose work has been published in national, regional, and online publications. Additionally, she has written articles as a newspaper correspondent. Visit http://www.fetchingsites.com/FreeFirewall.html to download a free firewall that is easytouse and will block hackers and other unknown threats.

This article was posted on December 12, 2004

by Heather Wallace

Improving SQL Performance

Improving SQL Performance

by: Marisa Pellegrino

How do you know how much hardware is really needed by your applications? And what do you do when your applications are overloading your system? The answer lies with improving your SQL performance. You have to tune your hardware SQL server and monitor performance, all of which will be explained as clearly as possible on this page.

The first thing to do when you want to improve your SQL performance is you need to learn how to optimize your system by finding out how much hardware you really need to run your applications. The best way to tune your hardware and monitor performance is through the art of performance monitoring which takes experience, knowledge, and sometimes even luck.

Performance monitoring guidelines:

Make sure you’re running your typical processes and work loads during the monitoring.

Don’t only do a realtime monitoring of your servers; capture long running logs.

Always have the disk counters turned ON.

Set up the chart windows with an interval of 18 seconds for routine, daily desktop monitoring.

Know the tools you are working with.

Don’t be afraid to experiment.

Know the terminology (ขobjectsข are lists of individual stats available; ขcounterข is a single stat; ขinstanceข is further breakdown of a counter stat into duplicate components).

A bottleneck happens when the hardware resources can’t keep up with the demands of the software. This is usually fixed in one of two ways: first, you identify the limiting hardware and increase its potential (i.e. a faster hard drive or increase the speed of the computer); second, make the software processes use the hardware more efficiently.

Five areas to watch when improving SQL performance and identifying bottlenecks:

Memory usage

CPU processor utilization

Disk input/output performance

User connections

Blocking locks

About The Author

Marisa Pellegrino is a freelance writer from Montreal and is the head researcher and content manager for www.sqlrecovery.com.

[email protected]

This article was posted on December 24, 2004

by Marisa Pellegrino

Microsoft Class Action Settlement in Minnesota S

Microsoft Class Action Settlement in Minnesota Submitting A Claim

by: John Gall

Microsoft has settled a class action lawsuit with the state of Minnesota. Based on this settlement software purchased between May 18, 1994 and March 17, 2003 may be eligible for a voucher that will provide additional monies to the claimant upon proof of both software purchase and a qualifying hardware or software purchase after July 1, 2004. Windows or MSDOS software is worth a $15.00 voucher while Microsoft Office and Excel is worth $23.00 Word, Works Suite, and Home Essentials 97 or 98 is only worth $9.00
The way it works:
To submit your claim visit http://www.microsoftminnesotasettlement.com and file a claim either as an individual or business using either a standard form or a volume license form. If you are lucky you will be filing an volume license form. Simply fill in the information related to your company and a Claims Administrator will do all the research for you. They will let you know which of your open or select license purchases qualify for the settlement voucher. Based on this you will receive the vouchers you are entitled to. If you have already purchased qualifying hardware or software after July 1, 2004 you can submit the proof of purchase with your settlement form. This will save you time as you will receive a check from Microsoft based on these purchases. Future purchases and be resubmitted for money based on the vouchers you received.
If you are filing a standard form you must supply product ID and purchase information. As with the volume license process you then receive vouchers which can be redeemed for hardware purchases made after July 1, 2004. If your claim is for five or fewer items and the value is less than $100.00 you can fill out the online claim form. You will need to have your product IDกs available to complete the form. All claim forms must be submitted on or before February 25
Whatกs a qualifying hardware or software purchase?
Qualifying hardware includes new desktop laptop or tablet computers. It also includes printers, scanners, monitors and even keyboards and pointing devices.
Qualifying software is any noncustom software which is used on qualifying hardware.
This brief article is only to serve as a quick read guide to obtaining your settlement. For all forms and detailed information please visit the official settlement site at http://www.microsoftminnesotasettlement.com. Here you will find all necessary forms and detailed instructions on filling out the forms. Be sure to read all forms and their instructions carefully to ensure you are providing the correct information regarding your claim.

About The Author

John Gall is a full time IT Manager and IT Consultant in Minnesota. He runs several websites as a hobby featuring content similar to that in this article.

http://www.gallconsulting.com

http://www.sandalspictures.com

http://www.napavalleypictures.com

http://www.winesilove.com

http://www.sturgistravels.com

http://www.hdsportsters.com

This article was posted on July 11, 2004

by John Gall