This is a dead simple driver for Mac OS X to revive the Bluetooth version of the Griffin Powermate in modern versions of OS X. Tested on Catalina (.15).
This app runs in the menu bar and sends and receives NSDistributedNotifications for knob actions.
The topic is kPowermateKnobNotification.
The values are:
kPowermateKnobPress,
kPowermateKnobRelease,
kPowermateKnobCounterClockwise,
kPowermateKnobClockwise,
kPowermateKnobPressedCounterClockwise,
kPowermateKnobPressedClockwise,
kPowermateKnobPressed1Second,
kPowermateKnobPressed2Second,
kPowermateKnobPressed3Second,
kPowermateKnobPressed4Second,
kPowermateKnobPressed5Second,
kPowermateKnobPressed6Second
Note that kPowermateKnobRelease is only sent after a long-press event, not after a single click.
Publish to the topic kPowermateLEDNotification.
It takes an NSDictionary userInfo with the keys fn and level.
Off and on (obviously) do not take levels. Just send kPowermateLEDOn or kPowermateLEDOff as the fn.
To dim the knob, send fn kPowermateLEDLevel with a float from 0 to 1.
To flash the knob, send fn kPowermateLEDFlash with an int 0-32, the higher the faster the flash.
I use this as volume/mute knob for Zoom, but the possibilities are endless with Hammerspoon. See knob.lua for an example on how to easily control your system volume and mute your mic with Hammerspoon. Of course, there are way more advanced setups. For example, you can make Hammerspoon look at the current foregrounded app and do specific things per app (scrub a timeline, scroll pages, etc.), or you could add multiple global modes.
Install and run Hammerspoon.
You need to install the MicMute Spoon. Just download and doubleclick.
Then, drop the contents of knob.lua into your Hammerspoon init.lua and reload the config. Download (or clone & compile) and then run this app.
You'll have to click your knob once or twice to wake it up and connect. Once it does, the menu bar item should change from ⭕ to 🎛️.
I hacked this together quickly to meet my needs but this is clearly that: a hack. Improvements welcome!
GNU GPL v3. See LICENSE