June 13, 2002

Plug and Play, or PnP, what is it and why do you care?

Well, PnP has made life much simpler when purchasing and installing hardware for computers.  Plug-and-Play automatically tells the software (device drivers) where to find various pieces of hardware (devices) such as modems, network cards, sound cards, etc.  Plug-and-Play's task is to match up physical devices with the software (device drivers) that operates them and to establish channels of communication between each physical device and its driver. 

Again, we'll bypass a lot of the technical stuff and concentrate on the basics.  In order for a device to work with your computer, it must be able to use the communication and drivers in order to do what it is supposed to do.  Prior to the hardware produced in the last couple of years, most all devices had their own plug-in cards (printed circuit boards) and it was necessary to have physical jumpers on the cards to setup the device so it wouldn't conflict with other devices on the computer.  Sometimes this was a task even for someone who knew what they were doing.

Today, in addition to plug-in cards, many "devices" are small chips permanently mounted on the "motherboard".  Furthermore, cards which plug into the motherboard may contain more than one device.  For the computer system to work right, each device must be under the control of its "device driver".  This is software which is a part of the operating system (perhaps loaded as a module) and runs on the CPU.  This also involves Memory addresses, IRQ channels, and direct memory access info (topics too involved for this discussion). 

Anyway, the newer computers and hardware do all the configuration stuff for you eliminating much of the time and expertise required to do these things so that's a major benefit of purchasing a newer system.  Of course, as time goes on, these features are also improved and make it much simpler to add hardware to the computer yourself.

If you have any questions or comments, please