I see the problem now: it is the "real time" patching.
What I forgot was the "/".
So it is/was my mistake.
I asume in the software uses an input state machine which knows about the next steps an input can go for. What about highlighting the next possible command key for a running input.
For example: if you select an Universe and a DMX addres at once and you select "Patch Fixture" than you could highlight the number keys and after you typed the first number the "/" could be highlighed to give a hint what can be done in the next step.
I tried many times the "@" key instead of "/" because I thought: "patch fixture 1 100@1" would be: patch fixture 1 on DMX 200 in Universe 1
But with such a highlighting one could give a hint to the user what is possible as next steps.
I created many input and processing state machines in my life as developer and from my experience there is a relativly easy way to do such a highlighting: In the state machine engine one can figure out which state transition key events are possible from the current state. That are exactkly the elemets to highlight, if a found transition reacts on an external key press.
Take it as a suggetions, not more.
My best regards,