Adding More Printers

No USB ports on your machine, or you want to use two parallel printers? PPC has the answers in this reader's query.

Q. I've read lots of reviews in various magazines that advise me to use a laser printer for monochrome only printing, but I already have an inkjet taking up my parallel port. I'm convinced that a laser printer would be a good idea, but how will I go about connecting two parallel interfaced printers at a time to my PC?

A. There is a number of ways you can go about this. The first, and probably the simplest, is to use a switch box. What that does is to split your parallel port two (or more) ways, with the proviso that only one of your connected printers can be functional at any one time. There are automatic boxes as well as manual, and they vary in price from around £15 upwards.

Manual boxes require you to physically turn a dial to point to the right printer for the job you're working on. If you get it wrong, it can all go horribly wrong, resulting in lots of wasted paper.

Automatic boxes, on the other hand, use a little bit of software to detect which printer you've selected in your application and make the selection accordingly. This kind of solution works very well - automatic boxes are available from all good suppliers, and you may like to consider the Belkin range. Be sure, though, to select the bi-directional version. The are unidirectional auto-switches available which won't always function properly with all printers.

USB to Parallel

Next up in terms of simplicity are USB to Parallel cables. According to the blurb, using one of these is a simple matter of connecting the cable up and changing the port your printer sits on from the parallel port to the USB driver. That's fine if your PC has USB ports and is running either Windows 98 or Windows 95OSR2. Any other operating system may not work with this solution. The upside of this is that you could, in theory, have a number of printers connected to your PC. On of my machines, for instance, hosts four USB connected printers (all native USB interfaces, I hasten to add), but it's not always possible to print to two of them simultaneously - not that that's usually a problem.

More Interfaces

The final solution is to add another parallel port to your PC. Again, this is a reasonably straightforward operation, if you can get your hands on a PCI parallel port card. Unfortunately, these beasts are all too rare, although they are available at the likes of Staples and PC World occasionally. You are more likely to be offered a multi-function card by a vendor, which offers a couple of serial ports, an IDE port or two, maybe a joystick port and lord knows what over and above the parallel port. Inevitably, these cards are ISA slot units, rather than PCI slot, and they're not likely to be plug and play. It can take quite some time to configure these cards to provide only a parallel connection, since the jumper settings tend to be documented in system-builder speak, and they're really not intended for ordinary folks to get involved with - or to provide just a second parallel port, to be fair.

If that's the route you want to follow, though, make sure that you take a complete listing of the IRQs that are trapped by existing cards and devices in your PC. To do this, right click on <My Computer>, select <Properties>, <Device Manager> and then double click on the <Computer> icon at the top of the screen. You'll be presented with a full listing of every IRQ your system is using.

You'll need to set the parallel card's IRQ to one that is not used by any other device - IRQ 7 is usually a good bet in Windows Me, Windows 98 and later versions of 95.

With that done, you can power down your machine and install the card. When next you boot, Windows ought to detect the new parallel port, and you can install your new printer on it.

Dave Dorn