Today we?re going to look at keyboards, the simple yet hugely important part of a computer that most of us take for granted.

There are two types of keyboard connections ? one, known as PS2, is the round one that we all know and love, colour coded on most PCs with purple for keyboard (green for mouse). This is the most common, and most of us will be familiar with it.

Secondly, some keyboards use USB (stands for Universal Serial Bus, and was covered in a previous article) to connect.

The only issue here, is that PS2 is a native and very stable protocol when it comes to computer motherboards, whereas USB, is still pretty much an infant, and as such, a little unpredictable. Thus, if you have any USB issues at all, a USB connected keyboard can be rendered useless, and suddenly all access to your computer ? even for troubleshooting purposes ? is revoked.

My advice, unless you have a newer PC which does not have PS2 connections, is to keep an old PS2 keyboard and mouse and put them in a safe place, even if you normally use your USB ones, so that you do ensure access in the event of a major PC problem involving your USB.

There are also ?wireless? keyboards ? that is, keyboards driven by infra-red, which allow you to have a wirefree desktop.

These are usually PS2 connected, have a little ?access-device? which will emit the infra-red beacon which must be in line-of-sight, or at least, extremely near (within one metre) the keyboard.

There are recorded issues with these types of devices, most notable is a time-out, that is, that after a long period of inactivity, the infra-red connection between the beacon and your keyboard will simply be forgotten. Quite literally, forgotten.

Thus, you have to try and force the two to detect one another again, and, my experience is that this is not always possible and a complete reboot of your system is required.

Lets look over the main problems associated with keyboards. Most problems with keyboards can usually be dealt with by cleaning the keyboard, or removing its device driver and rebooting the system.

Cleaning is not as obvious a fix as it may sound. You need to ensure no liquid enters the keyboard. The best and most prudent item is a soft damp (but not wet) cloth.

Additionally, it is a good idea to blast out the dust and other detritus from under the keys.

You do this with a small aerosol can of high-pressure air which you can get from most hardware or office supplies type store. Laptop keyboards can usually be removed and cleaned beneath without major problems.

If that does not do the job, then we need to uninstall the software that translates your keystrokes into letters on the screen.

Such software is called a device-driver, and there is one for every item of hardware on your computer. To remove the device driver (on Windows XP), ?right click? on ?My Computer? and select ?Properties?.

Go to the Hardware tab, and select the ?Device Manager? button. You will be presented with a ?family-tree? of the devices in your computer, and against each there will be a tiny ?+? (plus) sign, which you can click on to expand the contents.

Look down the list for ?Keyboards? and expand it, by clicking on the plus-sign. Most of the time, you will see one entry here, and it will be a standard keyboard.

Select it and press the ?Delete? key on your computer (only do this if you are experiencing some problems ? do not try this just for the sake of it!).

You may now find, depending on the type of keyboard you have, that you can now no longer type anything meaningful into the computer. This is normal, and you must now press and hold (for six seconds) your power button on your PC.

When you switch it back on, during the boot process (which we will cover in detail in a few weeks time), the keyboard will be reinstalled using a fresh copy of the device driver.

@EDITRULE:

Next week we look at the keyboard?s equally important counterpart ? the mouse.

Bob Mellor is a senior business technologist with nearly two decades experience. He is a Professional Member of the British Computer Society, and currently Technical Services Manager at Bermuda Microsystems Group. E-mail him at bobbmg.bm