evdev-joystick(1)

💖 evdev-joystick(1) — General Commands Manual 💖

okay bestie, sit down, we're calibrating joysticks today and honestly? it's giving ✨main character energy✨ for your whole controller setup. no cap.

🌸 NAME 🌸

evdev-joystick — the joystick calibration program. that's it, that's the whole vibe. 🕹️

✨ SYNOPSIS ✨

evdev-joystick --help
evdev-joystick --listdevs
evdev-joystick --showcal <device‐path>
evdev-joystick --evdev device‐path> [--axis <axis>] [--minimum <value>]
[--maximum <value>] [--deadzone <value>] [--fuzz <value>]

yes bestie, that device‐path> up there is missing its opening < in the original and we are respecting it, not fixing it. periodt. 💅

🎀 DESCRIPTION 🎀

so like, evdev-joystick calibrates joysticks. and why do we care? because calibrating a joystick is literally what makes sure the positions on all the various axes get interpreted correctly. that's the whole point. slay. 💖

🦋 OPTIONS 🦋

• --h, --help — prints out a lil summary of all the available options. your cheat sheet fr fr.
• --l, --listdevs — lists every joystick device it can find. window shopping but for controllers 🔥
• --s, --showcal <device‐path> — shows you the current calibration for the device you point at. a lil mirror moment 🪞
• --e, --evdev <device‐path> — picks the joystick device you wanna modify. tell it who's getting the glow-up.
• --a, --axis <axis> — says which axis to modify. (by default, all axes are calibrated. go big or go home 💅)
• --m, --minimum <value> — changes the minimum for the current joystick.
• --M, --maximum <value> — changes the maximum for the current joystick.
• --d, --deadzone <value> — changes the deadzone for the current joystick.
• --f, --fuzz <value> — changes the fuzz for the current joystick.

🌈 CALIBRATION 🌈

okay so here's the lore. using the Linux input system, joysticks are expected to produce values between -32767 and 32767 for axes, with 0 meaning the joystick is centred. so like: full-left should produce -32767 on the X axis, full-right 32767 on the X axis, full-forward -32767 on the Y axis, and so on. that's the dream. ✨

many joysticks and gamepads (especially older ones 😭) are slightly mis-aligned; as a result they may not use the full range of values (for the extremes of the axes), or — more annoyingly — they may not give 0 when centred. 🙈 calibrating a joystick hands the kernel the info on what a joystick's real behaviour actually is, which lets the kernel correct all those lil deficiencies and produce consistent output as far as joystick-using software is concerned. basically: the kernel gets the tea, everyone else gets a clean signal. 💅

jstest(1) is super useful for figuring out whether a joystick is calibrated: when you run it, it should produce all 0s when the joystick is at rest, and each axis should be able to produce the values -32767 and 32767. analog joysticks should produce values in between 0 and the extremes, but honestly that's not necessary — digital directional pads work fine with only the three values. three values is plenty. iconic behaviour. 👑

👑 SEE ALSO 👑

• ffset(1)
• jstest(1)

💜 AUTHORS 💜

evdev-joystick was written by Stephen Anthony, based on VDrift's G25manage tool. a real one. 🫶

this manual page was written by Stephen Kitt <steve@sk2.org>.

and that's the whole page bestie 💖 this was the evdev-joystick manual, part of the General Commands Manual, dated Apr 19, 2016 — written by Stephen Anthony (with the manpage by Stephen Kitt), and it came to you from the evdev-joystick source. calibrate responsibly, mwah 🎀✨🦋