Throwback tech: Taking a closer look at the original USB-to-PS/2 adapter

Editor's take: One of the first upgrades I bought for my very first computer around the turn of the century was a Microsoft IntelliMouse Explorer. Its standout feature was IntelliEye, an optical tracking system that replaced the traditional mouse ball and afforded unprecedented precision with minimal maintenance. The pointer shipped with a then-standard PS/2 port but also worked with USB when using the included adapter. What you may not know is that this small, green adapter was purely a mechanical component. As Microsoft's Raymond Chen recently explained, PS/2 and USB are completely different protocols that are not compatible in any way. The adapter simply connected one set of pins to another, but featured zero circuitry. Indeed, it was the mouse (or keyboard, or whatever other device you were trying to use) that did all the work. Chen likened the adapter to those inexpensive electrical outlet adapters popular among international travelers. In those, the adapter just connects one s ... Read full article.