# What is inside a PS2\>USB adaptor? **URL:** \ **Category:** Factual Questions\ **Created:** [July 29, 2003, 2:21pm UTC](https://boards.straightdope.com/t/what-is-inside-a-ps2-usb-adaptor/191652 "2003-07-29T14:21:51Z")\ **Posts on this page:** 3\ **Page:** 1
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [July 29, 2003, 2:21pm UTC](https://boards.straightdope.com/t/what-is-inside-a-ps2-usb-adaptor/191652/1 "2003-07-29T14:21:51Z")
You know, those little green adaptors that you sometimes get with USB mice, enabling them to plug into a PS2 port - do they have any/much in the way of circuitry inside, or is the gestalt of [electronics inside the mouse + software drivers] sufficient to make it a simple case of connecting things to the right place? ---
**Author:** ![scr4](https://avatars.discourse-cdn.com/v4/letter/s/59ef9b/32.png) [@scr4](https://boards.straightdope.com/u/scr4)\ **Post date:** [July 29, 2003, 2:52pm UTC](https://boards.straightdope.com/t/what-is-inside-a-ps2-usb-adaptor/191652/2 "2003-07-29T14:52:47Z")
I’ve taken one apart. There’s nothing in there, it’s just two connectors wired together. The circuit inside the mouse must be smart enough to figure out whether it’s connected to a USB or PS2 port and act accordingly. ---
**Author:** ![milk\_milk\_lemonade](https://avatars.discourse-cdn.com/v4/letter/m/ecccb3/32.png) [@milk\_milk\_lemonade](https://boards.straightdope.com/u/milk_milk_lemonade)\ **Post date:** [July 29, 2003, 3:16pm UTC](https://boards.straightdope.com/t/what-is-inside-a-ps2-usb-adaptor/191652/3 "2003-07-29T15:16:21Z")
Exactly as scr4 says. For what it’s worth the wiring goes like this: usb - ps/2 GND - 5 GND RxD - 2 RxD TxD - 3 TxD +5V - 7 RTS