Review on Logitech Brand PS2 Converter: Monoprice USB Male to PS2 Adapter (102209) by Kris Martin

It's important for people to understand that this is a passive converter. The USB ports have 2 data pins (D+ and D-), a Vcc pin and a GND pin. The PS/2 also has two data pins (DATA and CLK), a Vcc pin and a GND pin. This passive converter just routes the two data pins of the PS/2 port to the two data pins of the USB port and Vcc to Vcc and GND to GND. It is not actively converted between protocols. You can't just use this adapter to get a PS/2 keyboard working through a USB port as the CPU can't talk directly to a USB port, but most of them will work through a USB controller. and this USB controller only understands USB protocol and cannot understand PS/2. The converter only really works if you are using an older computer. Older computers use the PS/2 protocol over USB, and older USB keyboards therefore support the PS/2 protocol. So if you connect an old USB keyboard to an old computer, this adapter will work. But there is no other way. You must be sure that your device supports the PS/2 protocol over USB as most devices do not.