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How can you make a homemade ps/2 to usb converter for a ps/2 keyboard without buying one? Answered

I have an Inspiron 6000 laptop, and the keyboard and screen are broken. The screen issue I am not really worried about, as the laptop has a video out port, but the keyboard issue is quite annoying, as there are no ps/2 connectors on the laptop, and the only keyboard i have is ps/2. I have spare usb cords, and I am pretty sure my keyboard has a four pin connector, but just in case, i would like to know how to do it with four or six, or whatever the standard is.


Not sure of the pin out, but there's a ps/2 to usb converter made by zio tech that works perfectly converting my ancient IBM m4 keyboard with every usb motherboard that I've tried it on. So all that remains is to hide the converter withing an IBM m4 keyboard case and run a nice coiled usb cable from the inside of the keyboard to the computer.

Here is some pinouts.

USB mouse/keyboard to 5-Pin DIN or 6-Pin Mini-DIN adaptor

USB Function 5 Pin DIN 6 Pin ps/2
Pin 1 +5V Pin 5 Pin 4
Pin 2 -Data Pin 2 Pin 1
Pin 3 +Data/clock Pin 1 Pin 5
Pin 4 Ground Pin 4 Pin 3
shield shield shield

I also tried only to change the ps/2 keyboard jack a usb jack. But, it was not recognized by the computer. So it is not possible.

well, sir, a PS/2 port carries 3/4 signals. These signals are, Data+, Ground, and Power+5v DC. A USB cord also carries the 3 signals. However, 2 pins are not connected and are only used for filler. The last pin, however, carries a Clock signal.

Go here to find all the pinouts you want.

They are right that only a keyboard that has the usb mode built in will work. But in all the years I've been using computers when they switched to usb on MB's I've never had a keyboard that wouldn't work with an adapter. And the adapters were the cheap ones that had to have been just a pin changer with no electronics inside to convert the signal.

So maybe you'll have good luck. If the keyboard was one of the later ones it'll probably work if you wire it up correctly.

Usb can easily be made to work from a ps2 port but not the other way around.


8 years ago

ReCreate is right. You're looking to make a passive converter which is just a way to change the plug shape to fit the existing connection. No harm in trying because its an easy Mod. But, chances are pretty good a passive converter won't work. In which case you will need a signal converter to actually make your old keyboard work. If you need a USB keyboard, check out a thrift store, I regularly see 'em there for a couple of bucks.

PS/2 is more "analog" than USB, Thus, Never really works except for the rare cases when the keyboard can work in USB mode or PS/2 Mode. About making the converter, look up some pinouts of the 2.