first of thank you for your amazing work. I was always annoyed at the lack of support for MOST Bus. Your PiMost is exactly what i have been looking for.
As I have seen, nobody has tried to use it with a Mercedes yet. Since I have just bought a W211 E-Class with the Command system, I want to try to modernize it a bit and add bluetooth audio with steering wheel control. Since the Headunit and CD Changer only have power in and MOST, I need to tap into it.
As I understand streaming audio is part of the specification and should be exactly the same on all makes and models, correct? That would make it way easier to reverse engineer.
Also do you know how the can-bus is being transmitted over MOST? I haven’t found anything in that regard.
I’m waiting for the 12 Volt version of the PiMost so its easier to integrate into the car. Any ideas how long till it will be available (annoying question, i know. Sorry :D)
I already did some car hacking on BMW’s when I still had one and MOST was always annoying, but at least they had the courtesy to add some normal cables and can-bus directly to their systems.
Anyways, thank you for creating and publishing all the resources!
There has been a purchase for a mercedes, but unsure how far they have got with testing etc.
Streaming audio is part of the specification, and so far no car has not implemented it in the standard way. I would be suprised if any did, but there’s always a chance!
From my JLR experiments, can is translated in various ways, sometimes it is a copy and paste of the message to MOST, other times it is formatted in a more user friendly way.
An example of this is my parking sensors, on can they are transmitted in 5 bits, so all 8 sensors are 40bits spread accross 5 bytes. But on MOST they are translated to just 1 byte per sensor, so much cleaner!
That’s surprising - what version of Comand is in your car? Mine’s a 2009 r171, which has an NTG 2.5; with that head unit there is a quadlock connector on the back that has the MOST fibres, but also a bunch of other wires including a CAN pair.
(I don’t have my laptop with its 2020-ish copy of WIS nearby, but a w211 should definitely be old enough for the wiring diagrams to be present)
it’s a NTG 1. This version only has Most Bus connected, nothing else. In April of 2008 the NTG 2.5 was put into the W211. Since then the Quadlock was present.
Hi,
I’m bumping this thread because I also have a W211 with a Comand NTG1 so my use case overlaps.
When recently I learned of PiMost my “new project!” light immediately went on.
Rather than adding a PiMost as an additional audio device on the ring, I’m looking to completely replace the Comand headunit with a Raspberry.
I’m not sure if that would work 100% but I’d be willing to try. My goals would be:
Replace the Comand headunit with a RPi+PiMost with a touchscreen, running Crankshaft to get Android Auto functionality.
Streaming Android Auto audio (and in general, any RPi audio; might as well add a USB port, or maybe play YouTube or other streaming services on the RPi) onto the MOST ring.
Not requiring any cabling and keep using the stock Harman Kardon system via the AGW (Audio Gateway with radio tuner and amp in the back). Here I think the fact that Comand NTG1 has only power and MOST connections is an advantage - there’s also less to implement.
Controlling other devices, namely the radio tuner (located in AGW) and CD changer. The telephone module would not be needed anymore if using Android Auto and phone audio is streamed via the RPi+PiMost; my car does not have a TV tuner; and controlling the obsolete navi drive in the back is also moot if we can just navigate using Android Auto.
If possible, get and send CAN messages (which are communicated with MOST by the AGW) to enable steering wheel controls and light/dark mode switch.
If possible, add a DAB tuner component and stream the DAB audio via the RPi+PiMost.
Creating a modern UI on the RPi touchscreen to switch between Android Auto and other inputs (radio tuner or CD changer controlled via MOST, or USB input or DAB audio streamed from the RPi).
One of the things I’m not sure about is the authentication. The AGW is the MOST master device in the W211, so the RPi+PiMost would not need to be master and can run as a slave device of type matching the Comand. However, as far as I can find, both the AGW and the Comand headunit are required devices in the W211 and the entire multimedia system won’t work if not at least these 2 devices are present. So I assume there is some sort of check or authentication (anti-theft code?) done. That means in order to replace the head unit, the RPi+PiMost would need to emulate the messages for these checks the same way they are done by the Comand. @enfive: I saw another post of yours where you emulated the Comand GUI - did you also replace the entire Comand, or just add that screen as an additional device on the MOST ring? I’m curious if replacing the headunit entirely is doable.
Also, I’m unsure if the USB version or the HAT version of PiMost would be most appropriate here. For replacing the headunit, the HAT would perhaps be easier for packaging (I’d 3D-print a housing to hold the RPi+PiMost+touchscreen to fit in the Comand location in the dash), but development and debugging (for example, that authentication between AGW and headunit) would be easier on a USB version connected to a laptop…
Interesting project, it’s exactly as I have done on my XF, the PiMost + pi have replaced the OEM touchscreen, and I have incorporated all climate controls, player, radio etc into the pi app along with CarPlay.
When I find time (I have a baby on the way imminently!) I’ll do a bit more of a write up, it’s not straight forward, but it is doable!
I would 100% recommend getting a desktop setup replicating the car!
Im looking to replace my headunit too
I do have a Aliexpress Android Headunit that is supposed to be compatible (though still in its box), so that gives me a few options for testing and bench setups (once I can get a PiMost or USB [hint hint??] )
Looking forward to seeing an progress here