EV-Controls TC-2 CAN control functions?

I don't have a huge amount to say, Other than I also have a SDU that I'm still working out what control system to use.
The TC-2 is one of the control systems at the top of my list.

Zack and Christopher have used the TC-2 to control the SDU they put in their van, They may be a good source for a few questions. They are good blokes and their youtube series is pretty good.

I'm also looking at the AEM VCU200, I spoke with AEM about this, they have a drop in logic board for the LDU advertised atm, but tell me they are planning to release a drop in board for the SDU some time in Q2 2022. I haven't priced out the whole system yet but I expect it'll be expensive like the TC-2. The AEM VCU200 is a 'complete' central control unit, it interfaces with the bms, dc-dc, charger, coolant pumps and a bunch of other vehicle sub systems. It seems to be designed to replace the old wiring loom/fuse box with a modern PDM. Considering many parts of the old ICE wiring loom can potentially become obsolete once the ICE is removed, depending on your build plans, It could be easier in the long run to do a lot of the wiring from a clean slate and interface it to the existing chassis hardware. That possibly also depends on how much electronics and CAN systems you already have in the chassis though, But there is probably ways to integrate those CAN modules into the new controller. In my build, it is pretty basic chassis wise, Lights, indicators, wipers, power windows, door locks, simple stuff.

To my understanding of how the TC-2 works,(and other SDU controllers) almost all of the control to the Tesla drive unit is via CAN, other than the accelerator pedal and a brake input. The PNR drive control is via CAN signal, as is the regen control levels. The TC-2 outputs all the other signals outwards on CAN, they can be displayed on a screen, or via the app on an apple device over wifi. It also can control reverse lights and brake lights under regen, as well as the main contactors (and I think pre-charge?) including a lockout when the charge cable is connected.
I'm not all that clued up on apple products, I've never used or owned them, but in an email to EV-Controls they mentioned that Ipads can be set up to wake and sleep on a keyed input, so it can be integrated better into a car, instead of being something you need to switch on and off separately by difficult to access buttons on the side or something. I'm personally not a fan of the apple only app, they have no plans to release anything android based.
The TC-2 control unit physically looks very similar to a couple of other controllers on the market, Advantics VCU 2.0, Polykup VCU, I wonder if they are all the same internal board hardware with different control software for each seller? probably not though, maybe its a ground up built product, like the 057 controller.

Anyways, I'm by no means an expert on this, just what I've learned while researching my own project. Hope there is something there that helps.

After some discussions it looks like all existing CAN controller providers 057, ingenext and the common platform of EV-Controls/Advantics/Polykup do actually modify and re-program the existing drive unit firmware to make it work with their controllers. This is true for all S/X and 3/Y models of the drive train.

As they replace firmware with something unknown, in my eyes this entirely voids the CAN controller's only and single advantage: an unmodified, safer and potentially more efficient drive unit.

If they reprogram with a particular original Tesla firmware version, a hacked Tesla firmware - in order to e.g. remove immobilizer code - or if they replace it with their completely own software or maybe even violate GPL basing it on Johannes' OpenInverter code - they are not telling.

With CAN controllers you still don't have to open and re-wire the inverter and the modification is revertible for a resell. But OpenInverter had dozens if not hundreds of eyes reading and verifying the code and designs and we know exactly what we install. At least I as a software- and hardware engineer know. With CAN Controller firmware we get something, where we do not know if it is really Tesla's likely more efficient but hacked intellectual property, just a GPL violation or a home brew of unknown quality.

And I do not like the vendor's unwillingness to share information - unheard of in my own area of the software industry. While I totally appreciate others going for the easier option, my own personal decision is to give all my trust points out to OpenInverter.