Thanks very much for the extra details, Black Knight!
Ah, FL Studio... I didn't know there's extra scripts needed to support more than 8 faders for a Mackie Control surface. With most other DAWs, you can just connect two Proboxes, and arrange in what order you'd like the faders to appear.
As far as the touchscreens go... sounds like you don't connect them directly to the D8B, but to a Windows computer? How do the touchscreens control the D8B? Indirectly, via Mackie Control through FL Studio, or directly via a connection to the D8B?
So far, I've been trying to connect a USB touch-screen display directly to the D8B, but since there is no USB mouse support, this doesn't work. I was mainly focussed on trying to convert the USB HID-Device signal the touchscreen outputs, into PS/2 mouse data the D8B can understand... but no luck so far.
If I interpret what you wrote correctly, then you're not connecting the touchscreen's outputs to the D8B, but to the computer running FL Studio. Then the touch-screens would control FL Studio components, which control the D8B console in Mackie Control mode, via MIDI and the MCU protocol, right?
If so, that's not what I'm trying to do and won't help for my purposes. But that's awesome, if it does what you need!
What I mainly want to use the touchscreen for on the D8B, is to change D8B mixer settings... such as doing routing changes like input channel patching or BUS Assignments straight from the screen. MCU control won't help with that, I'm afraid.
Your approach gave me another idea, that I need to check into, though... the D8B has a list of MIDI parameters that are assignable. I didn't look yet, if this somehow allows me to make all these patching settings remotely via MIDI... and if so, maybe I could create a sort of touch-screen overlay that maps where the buttons on the D8B screen are, but have the USB out of the touchscreen go to the DAW (with a "virtual" screen that emulates the D8Bs on-screen control layout) and have the DAW send the needed MIDI parameters when the screen is clicked in certain areas... I could output that to the MIDI port for the D8B, and control it via touch-screen over the MIDI detour.
Hmm... anyway, just thinking out loud and it gives me something to play with next weekend, haha
Or DO you actually have the touchscreens connected to the D8B directly, somehow?
I'm using a 10-point ASUS touch-screen (VT229H) that cost $250 plus tax, and it has a USB out. It works fine on Windows 10 and macOS Big Sur (incl. 10-point DAW implementation via TUIO - e.g. in Studio One) , and even "functions" on Windows 98 using a D8B computer for the hardware (with a USB slot panel added), except for there being an offset between where I touch and where the mouse appears (it's b/c the video card doesn't support the resolution the touch screen expects).
So, the touch-screen hardware, and even the USB hardware port on a D8B rack unit will work for this... but the Mackie OS operating system doesn't have driver support for it, and I can't decrypt what I suspect are the renamed Command.com and Autoexec.bat files in Mackie's take on the DOS/Win9x OS, in order to have it load a USB mouse driver.
I was looking into IR Touchscreens as well (and am wondering if Mackie was planning to do that stock, since the newer board has an IrDA port on it... just speculating and not sure if that would even work for IR touchscreens with custom drivers), but the output for those is usually also USB... so, I expect the same behavior with being unable to translate the "incompatible" 10-point data they output via USB into PS/2... which can only deal with simple coordinates for mouse movements, and can't handle the extra data a multi-touch monitor outputs from what I now understand...
I did see some "industrial application" touch screens with RS232 outputs, and that may be my next attempt. Both Serial/RS232 ports on the D8B are already used up for communication with the console (and if there's no serial-mouse driver in the OS, this wouldn't help either, anyway), but RS232 should only transmit simple coordinates for the mouse, so it would likely be easier to convert to PS/2. Not sure...
Looks like I got a couple of avenues to explore, and your post definitely helped with thinking them up! (But if you connect the touch-screens to the D8B directly and that works... that's really the "holy grail" for me right now, so, if you got that going PLEEEEEEASE let me know how, haha!)
Anyway... again, your setup looks AMAZING and it sounds like it works exactly as you need it to! I hope I'll reach that point, too, eventually (but have a slightly different set of requirements for how I'd like to use my D8B).
Have fun with that setup! But looks like that's gonna be a given, anyway