Introduction: Turn a Trackpad From a Broken Laptop Into a PS/2 Mouse

A friend gave me a broken HP Pavilion laptop. With just a little work, you can remove the trackpad and connect to a PS/2 or 9-pin Serial port . Connect to your PC and use as a simple mouse, or even wire to an Arduino for a unique interface for your project. You can make this project entirely from recycled parts you may just have lying around.

What you need:
-trackpad (I used a Synaptics TM41PUZ307)
-male PS/2 connector with cable (or a 9-pin serial)
-multimeter
-soldering iron
-screwdriver
-razor blade
-electrical tape

Step 1: Remove Trackpad From Laptop

Unscrew all the parts to the trackpad. Gently pry up any plastic. I used a hair dryer to help loosen the glue that held the pad to the laptop palm rest.

Step 2: Salvage a PS/2 Cable

I removed the PS/2 cable from an old broken keyboard. Alternatively, you can also wire to a 9-pin Serial cable.

Step 3: Cofirm Pinout of PS/2 Cable

Use a multimeter to confirm what the pinout of the PS/2 cable is.
Your wire colors may differ, mine where as follows:
pin1 = DATA = Red
pin3 = GND = Grey
pin4 = +5V = Brown
pin5 = CLK = Yellow

Or, you can wire to a 9-pin Serial port old school mouse style. This is also nice idea to use on a desktop as a secondary mouse.
pin4 = DATA
pin5 = GND
pin7 = CLK
pin8 = +5V

*You could even wire to an AT keyboard.

Step 4: Find Pinout for Trackpad.

Use the Internet and search for the pinout of your pad. Or you could use your multimeter again.
Synaptics has a great resource for helping you determine the pinouts of many of their models HERE.
My Synaptics TM41PUZ307 wasn't on the list, but an internet search turned up this:
pin5/6 = GND
pin7/8 = CLK
pin9/10 = DATA
pin11/12 = +5V

Step 5: Solder

I used a razor blade to carefully cut the ribbon cable to connect the 4 wires from the PS/2 cable. A quick dab of some cooling solder (too hot and you'll destroy the cable) and some electrical tape to reinforce.

Step 6: Mount

Ok, you'll want to test first. Just plug it in quickly and the standard windows mouse driver should work just fine. Without installing any drivers, I was able to navigate the mouse, left click, and use the mouse scroll wheel. I mounted it on my keyboard for now. But I plan on eventually using it in an Arduino project. Details on interfacing a trackpad to an Arduino can be found HERE
If you wish to use with USB, you must purchase a "PS/2 to USB Keyboard and Mouse Converter."

Comments

author
antonewtr (author)2017-02-12

Hi,

I'm unable to find the datasheet/specs of my touchpad so I don't know the pinout...

Can someone tell me how to do so with a multimeter ?

Synaptics TM2997 / 920-002811-01rev2

Thanks

author
Afzal cassim (author)2016-01-15

Got a broken Toshiba LAPTOP from a friend & love to try this out!

author
sonicdude10 (author)2013-06-09

I have a pad from a now gone HP Pavillion laptop circa 2005 hooked to my desktop. I couldn't find the pinouts to it online but a little multimeter work found what I needed. It is a Synaptics model. Forgot the model and don't feel like pulling the tape off it to find the model number. The pinout was easy. There were only 6 points on the connection and 3 of them were GND. VCC was easy to find as well. That left the DATA and CLK to guess. 50/ 50 chance and I got it right first time. With the official Synaptics driver that was released around April I now have Mac like gesture abilities with it. I don't even have physical buttons since I set it up with all possible functions I use on my mouses with the driver on the right side of the pad.

Fun to use when I get tired of moving my whole arm around on the mouse.

author
NallelyG (author)sonicdude102015-10-28

im trying to determine pinout on a chromecast touch pad, the flex cable also has 6 pins. my question is how do you determine which cable is GND, VCC data and clk?

author
sonicdude10 (author)NallelyG2015-10-28

Chromecast touchpad? I looked but no such thing exists. Chromecast is a dedicated device for streaming media to from other devices. There is no mention of a dedicated chromecast touchpad anywhere. Best bet is to follow what I did to determine the power and ground connections. They will be thicker lines. The signal lines will be thin. Then you have to determine if it's PS/2 or USB as well as which ones are CLK and DATA (for PS/2) or DATA + and DATA - (for USB). Best bet is to look at the pad model label (if it's still on the pad) and see if you can find the tech specs for it. The wiring pinout will be in the specs if they can be found. That's all I can provide.

author
NallelyG (author)sonicdude102015-10-29

sorry I had a big mental fart. I meant chromebook -_- but thanks I'll look into that

author
didgitalpunk (author)2011-10-02

like recordmasta001 said, how do you right clik? but first of all, is it even possible to right click?
and for my own trackpad, i used a usb-B connector(went on pinout.ru and search for the usb connector page)
and i got help from this instrutables(thanks Jamby):
https://www.instructables.com/id/How-to-build-your-own-USB-Keylogger/step3/Solder-First-Zone/

author

look at step one again.

author
TCPMeta (author)2013-10-04

I need a pinout/diagram for a TM41PUG350

author
zapskate (author)2010-09-13

i don't know for sure but ctrl click should work!? try it out

author
VirtualBoxer (author)zapskate2013-06-28

Wait, what? That only works in Mac.

author
Admiral Sym (author)2013-03-19

Based on the button above the trackpad and the indicator lights below I have that same laptop and same exact trackpad. I will follow your steps quite nicely

author
Michael_Bell (author)2012-11-28

I'm working on a different project, but has anyone found a simple way to take the glue off of the sensor?

author
cheft (author)Michael_Bell2012-11-28

I used rubbing alcohol for those things, and a q-tip

author
darthvader39560 (author)2012-06-09

Does anybody have the pinout for the Synaptic TM-00372-005? If so please give it to me.

author
yaly (author)2012-05-10

Mine is TM-00372-011 I need pinout quick

author
yaly (author)yaly2012-05-10

please PM me

author
hg341 (author)2009-04-06

hum... any idea on how to do usb?

author
Fodaro (author)hg3412011-01-04

I believe that to adapt PS/2 to a USB port is a simple matter of connecting different pins of the PS/2 connector to pins on the USB plug. http://pinouts.ru/InputCables/usb_ps2_mouse_pinout.shtml looks like it's got a pin-out for it.

author
Kasm279 (author)hg3412010-12-21

Some trackpads are USB, depends on the model, but most aren't. Only one I can think of is the MacBook line's trackpads.

author
cheft (author)hg3412009-04-06

You'd need to purchase (or build) a 'USB to PS/2 mouse and Keyboard Converter'. Or you could salvage an old mouse and piggyback this onto it.

author
hg341 (author)cheft2009-04-07

hum i have a usb to ps/2 to din!

author
Kasm279 (author)2010-12-21

What model of HP laptop was that? Let me guess, death by overheating?

author
joearkay (author)2010-06-29

how do you right click though?!

author
etsitservice (author)2009-07-24

I like the idea, but where's the buttons? I understand that the actual touchpad unit does not contain mouse buttons, but how would they be added? Could I piggyback onto an old mouse for the button functionality?

author

On my mouse pad, the ribbon cable has 6 connectors: power, ground, data, clock, and two for buttons. The mouse pad may not have buttons on it, but it probably has the inputs for buttons. (On mine, the button lines are designed for buttons that short pull up resistors to ground. The lines are also protected by double diodes that clamp stray voltages to the power and ground lines.)

author
freerunnin1 (author)etsitservice2009-09-04

if you enable the number pad as a mouse can be done in control panel> accessibility options> mouse> use mouse keys then the 5 button will be left click and the button next to right ctrl will be left if he wires it up so he has extra buttons on the touch pad then it will be like a propper mouse :D

author
comsa42 (author)2010-03-31

You could also bun the cable on some models

author
f86sabre (author)2009-06-25

from an old mouse, otherwise the colors do not match

author
stephenniall (author)2009-04-19

Omg this is perfect i am gonna do this (have a trackpad in one of my drawers somewhere) and make a rubber pen for it n use it as a sorta mini graphics tablet

author
twocvbloke (author)2009-04-09

Cool, I have a spare touchpad from the old upper casing of my Tosh. Satellite A50 (was going to respray, but got parts from a Tecra A2), and I have always wanted to make use of a touchpad on a PC!!! :D With a little work, you could make a case for the touchpad and buttons using the old laptop's casing, and a bit of wood or a project box... :) I think I shall do this, just to see if I can... :D

author
jstelzer (author)2009-04-07

Any pictures of the wires all soldered and whatnot? How did you strip the ribbon wire to connect them?

author
cheft (author)jstelzer2009-04-09

I used the razor blade to carefully scrape the plastic on the cable. There are already small bits exposed on it, I just increased by 100%. I added a photo of the solder work. Sorry, my camera does not take close pictures well.

author
stone3408 (author)2009-04-07

Great job! I've been looking for this exact idea for soem time now for a specfic project. Thanks!

author
CameronSS (author)2009-04-06

Cool, now I don't feel guilty about not writing it up when I did this.

and I forgot to take pictures

and I mangled the soldering

author
munchman (author)2009-04-06

I love it. And I look forward to seeing the arduino project.

author
munchman (author)2009-04-06

Nice, will do this when I can dig up that old, broken laptop. Very Cool.

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