An ode to my trackball

Logitech Trackman Marble Trackball

2025-03-10 Added instructions below to shorten the USB cable.

Background

In the ‘90s the huge trend in peripherals was ergonomics. Early trackballs back then were pretty horrible. It was a mechanical ball mouse, just upside down. On a whim I bought a Logitech Marble Trackball way back in 2002 (Trackman ver in 2013).

It has some really advanced features (even by today’s standards):

The ball is bigger and had a pattern the led sensors could interpret accurately.
PS/2 & USB capatible. Remember this was released when Windows XP was current.
Ambidextrous design (Though I am a right-handed guy)
It was cheap when it came out. $22.69!
The later trackman version added 2 extra small buttons (worth it!)

Fast forward more than 20 years later, I am still using them (sadly they were discontinued a few years ago). The trackball is absolutly rock solid. I clean the sensors about once a year and have never had a mechanical breakdown. I’ve never had any fatigue or strain while using it countless hours a day.

Linux Use

Configuring for linux was not very intuitive but I managed to come up with a button mapping with Xorg that has served me well over the years. Ubuntu has an absolutely amazing page outlining all the functions.

Left/Right big buttons work as usual.
Middle click is pressing both left & right at the same time.
Left grey button is scroll mode. Hold down to engage scrolling with ball (both horizontal & vertical)
Right grey button is ‘Back’ button in a browser.

/etc/X11/xorg.conf.d/marble-mouse.conf

Section "InputClass"
    Identifier     "Marble Mouse"
    Option         "ButtonMapping" "1 2 3 4 5 6 7 9 8"
    Option         "Emulate3Buttons" "true"
    Option         "EmulateWheel" "true"
    Option         "EmulateWheelButton" "8"
    Option         "HorizontalScrolling" "true"
    Option         "MatchIsPointer" "on"
    Option         "MiddleEmulation" "true"
    Option         "ScrollButton" "8"
    Option         "ScrollMethod" "button"
    Option         "XAxisMapping" "6 7"
EndSection

Tech Specs

Model:  T-BC21
USB:    v1.x ID 046d:c408 Logitech, Inc. Marble Mouse (4-button)
DPI:    300
Cord:   6ft/1.83m
Width:  3.43in/87mm
Length: 6.5in/165mm
Height: 1.5in/42mm
Weight: 6.98oz/198g

Cable Shortening

When these trackballs were first released, it made sense to have a 6ft/1.83m cord to reach your tower PC on the floor. My latest (RasPi) keyboard has a USB hub which makes the long cord excessive. This can be true for those with laptops as well.

Logitech Trackman Marble Trackball Sort Cable

I did a tear down and found to my surprise the USB cable is plugged into it’s controller board (not soldered!). This is apparently common in most all pointing devices. You can even order replacement cables on ebay/amazon. I found this amazing reference on overclock that details the pinouts and connectors of all the major pointing devices.

The connector is “JST 2.0 PH 5-Pin”, you will need a specialized crimper and a LOT of patience.

Keep in mind you need a USB cable with 4 wires and a 5th (case ground) wire. I chopped a bunch and only had 4 wires. I ended up cutting the cable the trackball came with. This was a good thing because the cable has to be a fairly thin cable to route through the case.

In my example photo I cut it down to 7in/177.8mm. Keep in mind that a good part of that wire runs to the middle of the case so bear that in mind when considering length.

Created: 2024-04-14

Modified: 2025-03-10