Vida CEM swapping

[vtl]

Open p2 bootloader with reading and writing function is on its way.

That's really awesome!

[vtl]

P1 or P2 cracking needs a reliable 1us resolution. Anything capable of detecting CAN-L line transitions in 1 us or slightly less is fine.

[RickHaleParker]

On Github "Make it clear in schematic that it needs an external +5v power and co…"

12V - 24V input to 0.8V - 12V 3Amp output Mini Buck Converters $1.55. Power off the 12V line on the OBD2 connector.

[vtl]

Yes, any DC-DC will work.

FYI, Mark D. found that Teensy 3.x detects latency better than 4.x. He pushed a pull request to reduce 4.x frequency clock to 180 MHz, it got merged this morning. Those of us who have a problem with predictable latency detection may want to pull the change and give it a try.

Also Mark authored support for built-in CAN-controllers, only external CAN-transceiver is needed. Overall, supported hw configurations are:

Teensy 4.x + MCP2515
Teensy 4.x + built-in CAN
Teensy 3.x + built-in CAN

Works with P1 (thanks to Christian) and P2 Volvo platforms.

Which is pretty exciting to see This is a good example of how open source works: it quickly attracts mental power of many smart folks and rapidly accelerates a development of the product. People do their own research and either write new code themselves, like Christian or Mark did, or share a much valuable knowledge.

[RickHaleParker]

Yes, any DC-DC will work.

Any with the correct output.

* If the internal controllers are selected, the FlexCAN_T4 library must be
* available in your library (should already be present as part of Teensyduino).
* If it is missing it can be found here: https://github.com/tonton81/FlexCAN_T4
*
* External transcievers must be used to connect the Teensy to the CAN bus.

Transceiver is a pretty generic term that includes devices that could not possibly have anything to do with this.
What kind of Transceiver? Logic leveler ... ect.

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PS: Think I figured it out. Teensy 4.0 can receive but not transmit the CAN bus signals.
The transceiver one needs is called a CAN Transceiver.

Can_Transceiver.jpg (27.3 KiB) Viewed 1995 times

[T5Luke]

vtl, i think it would be nice if some command based menu would be added like press c for (c)rack, (e)nter pincode...
On point (r)ead i would add a reading function tomorrow for the users who cant wait to backup their cem. It would be nice if you could make this essential change in your source. When you already know the code it wont be needed to go through the detection routine again before you can read the flash. The overnext step after a flash writer would be a windows gui i can provide which should also compile on different os versions.

[vtl]

Transceiver is a pretty generic term that includes devices that could not possibly have anything to do with this.
What kind of Transceiver? Logic leveler ... ect.

-------------------------------------------------

PS: Think I figured it out. Teensy 4.0 can receive but not transmit the CAN bus signals.
The transceiver one needs is called a CAN Transceiver.

Yeah, sort of. CAN-bus needs a controller that will "speak" the protocol and a transceiver that will convert a digital signal coming from/to controller into a differential signal, and back. MCP2515 is a controller, it needs a transceiver, which is usually mounted on the same PCB as a separate chip. Various MCUs carry a built-in CAN-controller, so you only need to supply a CAN-transceiver.

[vtl]

vtl, i think it would be nice if some command based menu would be added like press c for (c)rack, (e)nter pincode...
On point (r)ead i would add a reading function tomorrow for the users who cant wait to backup their cem. It would be nice if you could make this essential change in your source. When you already know the code it wont be needed to go through the detection routine again before you can read the flash. The overnext step after a flash writer would be a windows gui i can provide which should also compile on different os versions.

I think this deserves a separate tool. Well, maybe Arduino can act as a bridge for both tasks (finding the PIN and working with the CEM flash), but an external software will be needed for sure.

I don't know much about Windows, only that you can wipe this junk out and install a real operating system: Linux...

[RickHaleParker]

I don't know much about Windows, only that you can wipe this junk out and install a real operating system: Linux...

Just bought a Apple iSight G5 on eBay. Going to swap the hard drive with a SSD then install MorphOS. Always wanted to try out MorphOS but never had compatible hardware until ... when it gets delivered in the next 7 days.

[gnalan]

I don't know much about Windows, only that you can wipe this junk out and install a real operating system: Linux...

Which distro do you use, or do you build your own from the command line?