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Upgrade 101-6 - External peripherals

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Copyright © Myles White, 1999

Preparation and cautions (READ THIS FIRST)

• Introduction to external peripherals
• Spotter's Guide
  • AT-Style cases/motherboards
  • ATX-Style cases/motherboards
• General notes on installing
  • Exceptions
• Questions?

In part Six of Upgrading 101, we're going to tackle some real basics and have a look at the proliferation of external ports on the back of your computer. This is a level 1 assignment (no tools, no opening the case and, unless you actually buy something, no cost).

There is no end of tempting products to buy to attach to your system. Some of them will have come with it, of course, such as a keyboard, mouse, and monitor. However, if you're like the majority of relatively new computer users, you shopped around before you bought a printer. If you've had your PC for a while, particularly if you use it a lot for a combination of home and business projects, you've also been tempted by digital cameras, scanners, possibly external storage alternatives, and perhaps either a cable or high-speed "xDSL" modem.

You can spend as little as $20 for a generic mouse if yours didn't survive (or respond) after our attempts to clean the little beggar a couple of weeks ago or you could opt for Microsoft's new Intellieye Explorer ($104.95) or Wacom's latest tablet - the Graphire - with pen and mouse for US$99 (about $149 Canadian).

You can spend over $5,000 for a colour laser printer, get a more modest colour inkjet for anywhere from over $600 to under $200, or head for the middle ground - a "personal" monochrome laser at anywhere from $379 (10 ppm, 600 dot-per-inch (dpi), Brother HL-1020) to over $1,600 (16 ppm, 1200 x 1200 dpi, Lexmark Optra S1625).

There are great cameras for under $2,000 (Kodak DC290 at $1,700) and some adequate ones for under $1,000 (Sony Mavica at around $900). Good scanners cost around $650 to $1,300 and there is a whole handful of serviceable, "home" units for under $400.

So it goes. Of course, before you selected the model you favoured and paid for it, you had a nice, long chat with the salesperson about the type and age of your computer, the operating system and version you use, and any specialized software you needed to run. And, of course, the nice salesperson told you, "Sure, that's no problem," and then wrote the specifics on your invoice, right?

Once you get your purchase home, let's go 'way out on a limb and suggest that you read the manuals that came, not only with your computer, but also with the new product. Still with me? Oh.

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Spotter's Guide

Well, let's take a tour of your PC, just in case those manuals are a little on the vague side. This will also be a helpful orientation tour if you have to move it and disconnect your existing peripherals in order to work inside it later. Somewhere near this article should be a pair of graphics, showing the back of two PCs, an older unit with what is known as an AT-style, Socket 7 motherboard and case - typical of 486s, early Pentium and Pentium MMX PCs, and systems based on either AMD Kn or IBM/Cyrix processors - and a newer ATX-style motherboard/case combo - typical of Pentium II, Pentium III, and Celeron-based systems.

Most of the elements will be common to both systems (serial ports, parallel port, game port, and VGA ports, for example), although their exact location may change. Whether some of the others are present will depend on the age of the computer and its internal components.

Your system may or may not have the smaller PS/2 connectors for keyboard and mouse, or it may have only one of them. Likewise, a newer ATX system won't have the larger style of keyboard port. It also may or may not have Universal Serial Bus (USB) connectors (newer systems will have one or two, older systems are less likely to have USB).

The game port for attaching a joystick or other game controller may be on a separate circuit board called an I/O board (for input/output) along with a parallel printer port. It could also be on your sound card (not pictured on the older system), and if your computer is old enough, could even be on your graphics adapter (near the VGA port). You may have one 9-pin serial port, two 9-pin ports, one each 9- and 25-pin ports, or two 25-pin ports (it all depends on the age of your computer).

Having one parallel port for printers and other devices is common.

If you have any additional controllers in your PC, such as an internal modem (not pictured on the older system), network card (not pictured on either one), or SCSI adapter (small computer systems interface, pictured only on the AT-style PC), there will be additional ports for phone lines, network cables, and external SCSI devices.

Did you note from the AT-style graphic that SCSI connectors come in three different flavours? It's a good idea, just in case you've forgotten, to double-check what type you have so that when you bring home an external SCSI device (scanner, printer, backup storage unit, CD-RW drive, etc.) you get a cable that matches what you've got to what you buy.

Particularly because older serial ports with 25-pin connectors appear exactly the same as printer ports, it's useful to keep the following in mind. At the PC end of things, serial ports always have pins showing (i.e., they're male), while parallel ports are always female when located on the PC. Conversely, ports on external serial devices are always female. Where connecting serial devices gets interesting is that there are the two sizes (9-pin and 25-pin). A modern PC will have 9-pin serial ports, but serial devices could have either type. You save trips to the store by checking both and getting either an appropriate cable or a short converter cable of the appropriate type.

Some of the confusion about 25-pin serial and parallel ports goes away when you look at the cables you use to connect a printer or external serial device (such as a modem). The parallel cable will have a 25-pin male plug at the PC end and will generally have a larger plug known as a Centronics connector at the printer end. The exception is for printers that have a relatively new parallel connector on them - one that doesn't look remotely like either parallel or serial cable ends. However, it's useful to know that there is a new form of port shipping on some printers - because traditionally, printers rarely include cables in the box. Ask the vendor before you leave the store about appropriate cabling.

A lot of the things you connect to your PC will need port/cable connector converters to make them work. We've talked about SCSI, parallel and serial cables, but there are also USB converters, serial to PS/2 converters, older keyboard to PS/2 converters, and so-called "gender changers" to allow you to hook cables together. There is also a growing collection of darned-near-anything-to-USB converters, too. If I look around my office, I see that I have more cables and converters with different ends than I can shake a stick at. They seem to breed when I'm not looking.

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General notes on installing

How you go about installing an external peripheral will vary slightly from case to case, but there are some general guidelines (and one special one that applies to monitors). Once you've found a comfortable, stable place to put your device, the trick to avoid making yourself crazy is to "dress" any cables so that they're more or less out of sight. You don't want to run them under carpets, near telephones or radios, or hanging over fluorescent lights (or other sources of magnetic, radio frequency, or electrical interference). For certain, you want to keep them away from heat vents and open electric heaters. If you have pets who like to chew, keep an eye on them.

If your device is a printer, your first surprise is that it won't like being across the room from you. Unless you buy a specially shielded cable, the maximum suggested distance from the PC is about eight feet. Beyond that, without shielding, parallel cables are subject to all kinds of weirdness that translates into a printer that produces garbage. Alternatives here include printers with Ethernet or other network protocol adapters (or using an older computer with a network card in it acting as a print server), special converters that can act as bridge for a long serial cable, or a printer that connects to your PC via USB (where you can use up to 50-foot cables, with 12 feet being quite common).

Most external devices like to be attached to your PC before you install their software drivers. The install routine for Hewlett Packard's print drivers, for example, usually checks on the existence of the printer before it will work. And this may be the point at which we should discuss drivers. These are not the people you yelled at on the way to work today; instead they're tiny software programs that translate what your computer is doing into language the external device understands (and often vice versa, too). Software drivers are usually operating system (OS)-specific and more often than not, they're sensitive to the precise version of the OS you're using.

For example, most Windows 3.1x drivers don't work well under Windows 9x. Many Windows 95 drivers needed upgrades before working properly with Windows 98. If your new device isn't working, it's always possible you got a dud, but it's far more likely that it's a driver compatibility problem. This is why you discuss this with the vendor before you leave the store.

Device drivers are software (I know I've said that), but because they are, they're subject to the same number of bugs - and bug fixes - as the other software programs you use on your system. And their developers are always tweaking them. So, as soon as you get your new toy home, get on the Internet (or get a friend with an account to help). Go the company's Web site (it's usually listed in the manual, but generally follows the convention of www.<companyname>.com) and check to see if there have been any driver updates since the device was packed at the factory. Do not be surprised if there have been.

Once you have the correct drivers in hand, and have read the manual that came with the device to find out when to install the software, it's always a good idea to power your system down before attaching an external device - particularly a parallel device because the parallel port can carry power as well as data. Here, too, there's an exception we'll touch upon below.

When you attach the appropriate cable to both your computer and the device, take the time to tighten any screws or (in the case of Centronics connectors) spring latches to make the connection firm. Loose connections are, after driver oddities, the next most common cause of apparent device failure or intermittent operation.

Start your system. If you're running Windows 95 or 98, it should detect the new device and start the software driver installation routine. Consult the device manual.

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Exceptions

I said above that monitors deserved special attention. Your current monitor gets information from your graphics controller on how many pixels (picture elements) to display on screen (the resolution). When resolution changes, the monitor adjusts its frequencies to match. It's unlikely you're buying a new monitor that is less robust than your current one, but for ease of setup - and to avoid potentially harming your new monitor, set your resolution to 640 by 480 before you power your system down. You can readjust it later. Also, don't forget, when powering your system back up, to turn your monitor on before your computer; otherwise, the graphics card doesn't get the feedback it needs to work with the monitor correctly.

There's also an exception to the "power down before connecting" rule that applies only to Universal Serial Bus (USB) devices. Unless the device manual says otherwise, the majority of USB devices are designed to be connected while the system is powered up. Windows should detect the new device immediately and take the appropriate action to request any software drivers it needs.

Questions?

Send your query to troubleshooter@computerwriter.com or by fax at 416-425-4644. Components for this series have been provided by Grey-Tech Computers Inc., Markham, Ont. www.greytech.com 

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Part 7, Installing sound cards and modems (available only after Nov 4/99)