Only want MIDI output, not the keystroke

[ThomasMavian]

Hi all...

I've tried to search but it's so hard to navigate the answers on this particular question, so sorry if it may have popped up somewhere before.

I have an external USB NumPad which I'd like to convert to MIDI-messages. No problem, works great and all but I don't want the key from the numpad to reach my apps, I only want to output MIDI.

I'm clueless. Searched actions for "disable", "stop", "break", "block" and the like but I haven't found anything working yet.

Thanks for reading!

[ThomasMavian]

Anyone?!?

[tiffle]

Hi @ThomasMavian - welcome!

@ThomasMavian

I have an external USB NumPad which I'd like to convert to MIDI-messages. No problem, works great and all

It would help if you posted the KM macro you're using to achieve this and then we might be able to suggest a solution.

See this:

How Do I Get The Best Answer in the Shortest Time to Questions on the KM Forum?

Tip: How Do I Get The Best Answer in the Shortest Time? Summary: The better quality and more complete the information you post about your issue, the quicker we can give you a useful answer. Tell us your complete workflow along with your end-objective up front – do not spoon-feed it to us one post at a time -- i.e. don't waste your time or ours. At the very least provide a summary of what you're doing. By having a more complete picture of your task we can often suggest more efficient me…

[ThomasMavian]

Ok, sorry but I thought this was a kind of a pretty straightforward question: how do you stop a keystroke to reach the application?

I haven't found any "evidence" that Keyboard Maestro can do that, yet.

The macro is very basic, take a look at the screenshot.

[tiffle]

Just found this in the KM forum:

Device Trigger

What happens if you do not have the macro enabled at all and you press the TAB key? The thing with USB Device Key triggers is that they do not interfere with the normal behaviour of the key/button at all, they just detect it. So the trigger itself will have no affect on the keyboard or number pad. The TAB key might, or the macro might do something that affects things, but the trigger just detects the device change.

Sounds like there is no way to swallow the keypress from a USB device (cf. the final post in that thread). That's about as far as my knowledge extends. Maybe someone else here has an approach for you that might work.

[ThomasMavian]

Thanks, I figured that was the case. Well, then it's "back" to ControllerMate for this purpose I guess. ControllerMate captures/hijacks the key presses and then you can do what you want (for example not letting it through).

ControllerMate shouldn't work on Catalina but mine does. Probably because I did an update instead of a new install from High Sierra.

[peternlewis]

Hot keys will swallow the keystroke, but will not be able to differentiate different keyboards.

USB Device Key triggers cannot swallow the keystroke (at the level they are implemented, they are not even keys yet).

Event Taps can process events and can swallow keys, but if you do swallow a keystroke and then optionally let it through later, you will get out of order key events which leads to all sorts of problems.

Karabiner may be able to remap the keys on the device to something unique that could then be used with hot keys, or remap them to keys that will be ignored (like F20).

[ThomasMavian]

Thanks Peter.

I've actually already done what you recommend, I installed USB Overdrive to remap the keys to SHIFT+CMD+OPT+FunctionKey just to not trigger anything in any application. So now I have an external Numpad converted into MIDI.