Question about device controller?

Question

So from what I understand is that the device controller is a piece of hardware in the computer system that is connected to your device when you plug it in into a plug and socket.

From what I understand is that every particular device requires its own type of device controller.  A keyboard device requires that kind of controller, a mouse device requires that kind of controller, etc.

But majority of device slots in a modern computer system (apart from the Ethernet and HDMI, but I'm not getting into that) are just plain USB slots.  I can connect a mouse to USB Slot X, or a keyboard, or a camera... no problem.  So I can't seem to wrap my mind around how device controllers work.  Is there a universal device controller that manages all USB peripherals?

Joe · Answer

Part of your confusion comes from the timeline.  USB is a relatively new technology.  Prior to its adoption, computers would have dedicated, and unique, connectors and controllers for things like keyboards, mouses, and printers.

USB - Universal Serial Buss - changed all that.  It's a BUSS; that means that it can handle multiple devices at the same time, and in the same way.  Yes, your computer does have a single USB controller, capable of supporting multiple devices at the same time, since they all speak the same electronic "language".

It was a big improvement, and one of the reasons that computer price / performance keeps getting better.

Question about device controller?

1 Answer