Arduino Joystick Library, LinuxCNC joypad and hal_input

I’ve searched through the forums and could not find any reference to this so I’m passing on the information. Recently I’ve been working with an Arduino Micro on a project. While doing research I came across a Arduino library that can change a Micro to act as joystick.

github.com/MHeironimus/ArduinoJoystickLibrary/tree/version-2.0

The author states that you can create a joystick with the following features.

Buttons (default: 32)
Up to 2 Hat Switches
X, Y, and/or Z Axis (up to 16-bit precision)
X, Y, and/or Z Axis Rotation (up to 16-bit precision)
Rudder (up to 16-bit precision)
Throttle (up to 16-bit precision)
Accelerator (up to 16-bit precision)
Brake (up to 16-bit precision)
Steering (up to 16-bit precision)

I currently use a joystick (joypad) on my CNC mill and was curious if I could get the Arduino Micro working with hal_input on my mill. I loaded one of the example sketches for the joystick library and ran “less /proc/bus/input/devices” and got the following results:

I: Bus=0003 Vendor=2341 Product=8037 Version=0101
N: Name="Arduino LLC Arduino Micro"
P: Phys=usb-0000:00:14.0-8/input2
S: Sysfs=/devices/pci0000:00/0000:00:14.0/usb2/2-8/2-8:1.2/0003:2341:8037.0004/input/input19
U: Uniq=HIDHF
H: Handlers=event15 js1
B: PROP=0
B: EV=1b
B: KEY=ffff 0 0 0 0
B: ABS=7ff
B: MSC=10

I followed with

halrun

loadusr -W hal_input -KRAL Micro

Connected with no errors. Running “show all” revealed several pins. Here’s a partial list.

Component Pins:
Owner Type Dir Value Name
6 s32 IN 4095 input.0.abs-x-flat
6 s32 IN 255 input.0.abs-x-fuzz
6 bit OUT TRUE input.0.abs-x-is-neg
6 bit OUT FALSE input.0.abs-x-is-pos
6 float IN 0 input.0.abs-x-offset
6 float OUT -1 input.0.abs-x-position
6 float IN 32767 input.0.abs-x-scale
6 s32 OUT -32767 input.0.abs-y-counts
6 s32 IN 4095 input.0.abs-y-flat
6 s32 IN 255 input.0.abs-y-fuzz
6 bit OUT TRUE input.0.abs-y-is-neg
6 bit OUT FALSE input.0.abs-y-is-pos
6 float IN 0 input.0.abs-y-offset
6 float OUT -1 input.0.abs-y-position
6 float IN 32767 input.0.abs-y-scale
6 s32 OUT -32767 input.0.abs-z-counts
6 s32 IN 4095 input.0.abs-z-flat
6 s32 IN 255 input.0.abs-z-fuzz
6 bit OUT TRUE input.0.abs-z-is-neg
6 bit OUT FALSE input.0.abs-z-is-pos

I then verified with halmeter that I was getting input pins to work, which was successful.

From there I breadboarded a membrane keypad, a cheap rotary encoder and frankensteined some code from various web sites to create an arduino sketch. Again, I verified that buttons and the rotary encoder worked with halmeter. I have not tried to move my mill with the encoder. I’m not sure what settings I would need to get it to work in a hal file but I will continue to work with it.

My hope is the someone will find this useful. Please let me know if you do.