Vida CEM swapping

MaxDenisov · Post by **MaxDenisov** » 13 Apr 2021, 15:51

T5Luke just saved me from the fridge)
Thank you very much!

Engine working well now

Post by **RickHaleParker** » 13 Apr 2021, 15:56

T5Luke wrote: 13 Apr 2021, 03:03 For me it looks like to much noise on the can bus, i dont trust this 3,3V transceivers.

Ordered some 3V - 5V CAN Transceivers based on the NPX TJA1051. Should be here next week. I'll run them at 5V and see if it makes a difference. Will post the log with no other changes in test conditions.

Post by **vtl** » 13 Apr 2021, 16:02

T5Luke wrote: 13 Apr 2021, 15:37 Good idea, the jump in would be easy, but what about the jump out, there is no RTS near, also we need to manipulate the ram the [FB] is pointing to.

How about flashing a modified dump, with RET on the needed place?

T5Luke · Post by **T5Luke** » 13 Apr 2021, 16:07

Yes, for testing only this should work, i will try to prepare...

Post by **vtl** » 13 Apr 2021, 16:24

T5Luke wrote: 13 Apr 2021, 16:07 Yes, for testing only this should work, i will try to prepare...

The point here is to measure latency with the cmp code placed at different addresses.

Post by **RickHaleParker** » 13 Apr 2021, 18:28

Updated CEM part number list, All are verified by looking at the CEM and label, except 30759114 which I cannot determine if it is CEM-L or CEM-H. When you run the CEM cracker watch the "Hardware id" and check it against this list. If you come across a CEM part number not on this list let me know.

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

P1 CEM Part numbers.
8690719 | 8690720 | 30728906 | 30765015 | 31254317 | 31327215 | 3125903 | 31254749 | 30765471 |

P2 CEM-B (Brick shaped 1999-2004 with K-line ) Part numbers.
8645716 | 8645719 | 8688434 | 8688436 | 8688513 | 30657629 | 9494336 | 9494594 | 8645171 | 9452553 | 8645205 | 9452596

P2 CEM-L ( L shaped and marked L 2005 - 2014 ) Part numbers.
30682981 | | 30728542 | 30765149 | 30765646 | 30786475 | 30786889 | 31282457 | 31314468 |

P2 CEM-H ( L shaped and marked H 2005 - 2014 ( Some sources are saying as early as 2003 but not verified ))
30786476 | 30728539 | 30682982 | 30728357 | 30765148 | 30765643 | 30786476 | 30786890 | 30795115 | 31282455 | 31394157 | 31282455

Notes: 30759114 listed as a L shaped P2 CEM. Unable to determine if it is a CEM-L or CEM-H. Cannot find the 1000 word picture.

Post by **vtl** » 13 Apr 2021, 19:01

Excellent list! I think the code can query the part number and tune CAN buses and internal routines and configuration properly, so no edit/recompile/upload cycle would be required.

Post by **RickHaleParker** » 13 Apr 2021, 19:07

vtl wrote: 13 Apr 2021, 19:01 Excellent list! I think the code can query the part number and tune CAN buses and internal routines and configuration properly, so no edit/recompile/upload cycle would be required.

That is the idea ... Auto-configuration.
If we can find some way to interrogate the development board and get an ID. We could do full Auto-configuration.

Post by **RickHaleParker** » 13 Apr 2021, 19:33

RickHaleParker wrote: 13 Apr 2021, 19:07 If we can find some way to interrogate the development board and get an ID. We could do full Auto-configuration.

Is this what I think it is? I am only about 4 Chapters into Arduino C. I'm a Grasshopper on this subject.

https://github.com/MattFryer/Board_Identify

5ft24 · Post by **5ft24** » 13 Apr 2021, 21:34

I can verify 30728539. 2005 XC90 V8 AWD