I got to thinking that their might actually be quite a simple solution that does not take up too much resources, and a patch bay type scenario is just one of many that could easily be adapted. I am not Synth guy, so please bare with me.
The way I see it, just like in an object, we want to go from somewhere to somewhere, in this setup, you could go A to B, A to B to C, but not B to A, C to A or C to B.
In this example, lets focus on A to B.
In the Axo patch,
- B is a monopole dial connected to a midi CC value.
- A is a Midi Internal send object where the CC value is connected a value read from an analogue input pin.
In the hardware,
- Build an output port for B with Resistor / 3.3V / GND setup to create a unique analogue value sent out of port B, single wire only required.
- Build an input port for A connected to an analogue pin so the unique analogue value read will set the CC value on the midi internal send object to the same CC value set on the monopole dial that you want the values to go to.
The above describes a simple approach that could easily be expanded in a patch without too much impact on resources, not only that, it should work fine in live mode, might be a bit twitchy when connecting depending on the plugs you use, but I think what I like about it is, it could easily be extended to other styles without patch cords etc.. and it could easily be implemented between several Axo boards as well.
I am sure that are many ways the idea could be fine tuned, but there it is.
I hope I have explained it well enough to get the idea across.