Vida CEM swapping

[Scoloo]

I understand what you're saying (I hope) and the same with p3? I certainly don't have the knowledge to put something like that together. I was hoping that I can create something like modunlock has. For a normal price

Soldering and ordering parts is no problem for me but the rest.... he uses a button to switch between p1 p2 and p3. I'm trying to find out how this works with teensy but with almost zero coding knowledge this is gonna be hard.

[al1Volvo]

We can maybe simple merge branch's code into one and just change cemCrackPin function into cemCrackPin_p1, cemCrackPin_P2 and cemCrackPin_P3, make the detection using the part number before and the switch on the correct function. Just an idea ...

[Scoloo]

That sounds the most easy way. I was wondering which way I need to connect a button and an oled screen to switch between the branches. Like 3 programs on the teensy. And then select with the button. Also, I would be nice if the code from vtl seed-gen.c goes automatically.

It would be fun to make the project the same as modunlock, just to piss him off

I've been reading this whole topic and I'm curious enough to order a modunlock and reverse engineer it with help from here.

[al1Volvo]

The ultimate things would be to dump the CEM to a SD card on the Tennsy, use an LCD screen to change the car config then apply it directly from the Tennsy without the need of a Dice or a computer !

[dikidera]

For that you need an sbl. A piece of software that runs exclusively on the cem that will start dumping the firmware and then also allow you to flash it back.

For the other things you need a button and literally beginner level tutorials on youtube for switching between modes.

[al1Volvo]

Handling multiple SBL using a SD card should not be a big deal, the big deal is getting the SBL for all possible config platform. Is there a way to find some existing open source SBL somewhere ?

[Scoloo]

I think that will be a hard job. Both finding them and also programming.

I believe there's no real need for it, because when you have the PIN there are enough other programs that can change it.

@dikidera : what kind of lcd should be best? Because it will also be possible to use led's for the modes. Like p1 green, p2 red, p3 blue.

I'm reading a little about switching between modes but can you point me on some good info? Than I can read and will work it out as a project in spare time. Making a schematic is not a problem for me.

[vtl]

Here is my question, I understand now a little bit how everything works. Also that for P3 I need to load my teensy with the other branch. But how is it possible that modunlock (who get the info from here) gets everything (p1, p2 and p3) from 1 device?

Combining all the cracking methods into one piece of software is not difficult. Just a matter of spending time.

But.

As an owner of Volvo, you need to crack the pin code only once in car's life. Loading up a code from specific branch is totally fine for that matter.

[dikidera]

Yes there are no open source sbls yet. Especially for the cem.

As for displays, any spi or i2c display will suffice. The cheapest will do.

Since teensy can be programmed with Arduino sdk this video is excellent

For simple pin cracking, very little logic is needed to switch between p1,p2,p3.

However for sbl things are complicated, you need to also understand how to communicate with can bus, the internal volcano protocol , how to set all can bus modules to sleep. How to write the sbl(which you also need) and how to setup two way communication. This will not be easy.

[Scoloo]

Here is my question, I understand now a little bit how everything works. Also that for P3 I need to load my teensy with the other branch. But how is it possible that modunlock (who get the info from here) gets everything (p1, p2 and p3) from 1 device?

Combining all the cracking methods into one piece of software is not difficult. Just a matter of spending time.

But.

As an owner of Volvo, you need to crack the pin code only once in car's life. Loading up a code from specific branch is totally fine for that matter.

That's true, but as a mechanic my only use will be giving second hand CEM's another live. Nothing more, nothing less. In that case it's easier if everything is in one place. I don't know what the CEM prices are in your country but overhere they're like €1000 excl vat. A secondhand one is about €100. So, I invested in io terminal for this case and used the build for the PIN. Which worked great off course.

I have no intention to sell something like modunlock but I just wanna help my customers.