A warning about the Jog Wheel


shuttlexpress − control HAL pins with the ShuttleXpress device made by Contour Design


loadusr shuttlexpress [DEVICE ...]


shuttlexpress is a non-realtime HAL component that interfaces Contour Design’s ShuttleXpress device with LinuxCNC’s HAL.

If the driver is started without command-line arguments, it will probe all /dev/hidraw* device files for ShuttleXpress devices, and use all devices found. If it is started with command-line arguments, it will only probe the devices specified.

The ShuttleXpress has five momentary buttons, a 10 counts/revolution jog wheel with detents, and a 15-position spring-loaded outer wheel that returns to center when released.


The shuttlexpress module needs read permission to the ShuttleXpress /dev/hidraw* device files. This can be accomplished by adding a file /etc/udev/rules.d/99−shuttlexpress.rules, with the following contents:

SUBSYSTEM=="hidraw", ATTRS{idVendor}=="0b33", ATTRS{idProduct}=="0020", MODE="0444"

The LinuxCNC Debian package installs an appropriate udev file automatically, but if you are building LinuxCNC from source and are not using the Debian packaging you’ll need to install this file by hand.

A warning about the Jog Wheel

The ShuttleXpress device has an internal 8-bit counter for the current jog-wheel position. The shuttlexpress driver can not know this value until the ShuttleXpress device sends its first event. When the first event comes into the driver, the driver uses the device’s reported jog-wheel position to initialize counts to 0.

This means that if the first event is generated by a jog-wheel move, that first move will be lost.

Any user interaction with the ShuttleXpress device will generate an event, informing the driver of the jog-wheel position. So if you (for example) push one of the buttons at startup, the jog-wheel will work fine and notice the first click.


(bit out) shuttlexpress.0.button−0
(bit out) shuttlexpress.0.button−0−not
(bit out) shuttlexpress.0.button−1
(bit out) shuttlexpress.0.button−1−not
(bit out) shuttlexpress.0.button−2
(bit out) shuttlexpress.0.button−2−not
(bit out) shuttlexpress.0.button−3
(bit out) shuttlexpress.0.button−3−not
(bit out) shuttlexpress.0.button−4
(bit out) shuttlexpress.0.button−4−not

The five buttons around the outside, starting with the
counter-clockwise-most one.

(s32 out) shuttlexpress.0.counts

Accumulated counts from the jog wheel (the inner wheel).

(s32 out) shuttlexpress.0.spring−wheel−s32

The current deflection of the spring-wheel (the outer wheel).
It’s 0 at rest, and ranges from −7 at the counter-clockwise
extreme to +7 at the clockwise extreme.

(float out) shuttlexpress.0.spring−wheel−f

The current deflection of the spring-wheel (the outer wheel).
It’s 0.0 at rest, −1.0 at the counter-clockwise extreme, and +1.0
at the clockwise extreme. (The ShuttleXpress device reports the
spring-wheel position as an integer from −7 to +7, so this pin
reports only 15 discrete values in its range.)