Vida CEM swapping

Post by **vtl** » 24 Apr 2021, 09:35

Yes, go to Saleae web site and download the sw for your OS.

Post by **RickHaleParker** » 24 Apr 2021, 11:36

vtl wrote: 24 Apr 2021, 09:35 Yes, go to Saleae web site and download the sw for your OS.

Got it.

I did find a Cross Platform, Open Source, Signal analysis software suite that support a lot of hardware, including the $10.00 Logic Analyzers. The sigrok project.

MaxDenisov · Post by **MaxDenisov** » 24 Apr 2021, 12:57

@vtl I am working on new pc/hardware design. Please let me know if you are interesting in spare pcb/device

3r1k · Post by **3r1k** » 24 Apr 2021, 16:49

T5Luke wrote: 24 Apr 2021, 08:08 Anybody has Dice, CODE and likes to try?
Only tested 1 time on bench and it worked. CEM allows only 100 write cycles so i dont like to do endless tests.

There are some small things i need to fix, if tests work 3 times i will upload here for all...

I would be very happy to try this out on my junk-bench CEM which i already know the pin for (used a parallel BCM interface to get it). But this comes from a MY04 P1 car = old style CEM (CEM-B??), does your program still works for this old Motorola processor based CEM?

Also, why are you limited to 100 write cycles? Is it the recommended hardware write limit of the MCU or something else?

T5Luke · Post by **T5Luke** » 24 Apr 2021, 16:56

This programm is for the P2 CEM from 2005 and newer, when we can crack the earlier one by teensy i can adopt to this also.
In datasheet is written about 100 write cycles, the early one can do 10 000 without a prob.

In total i have rewritten my bench CEM now 6 times by this prog, i can say it seems to work, but it would be nice if we find some more testers...

3r1k · Post by **3r1k** » 24 Apr 2021, 17:06

Ah, understandable. Hook me up in the future if you need testing for this older platform.

I also have a bunch of P1 CEM I am more than interested into getting hacked over the canbus, rather than solder manually.

Fun fact, here in this Volvo country it is cheaper to buy a whole CEM at the junkjard than buying separate relays/fuses placed in the CEM. Cost about 5 EUR at the local junkjard. If shipping wasn't that expensive I would have been more than happy to supply you guys with some...

Post by **RickHaleParker** » 25 Apr 2021, 02:52

If the pincode bytes are 8 bit BCD ( Range 00 - 99 ) why is the pincode BCD expressed as a hexadecimal?

found PIN: 0x25 0x43 0x27 0x93 0x52 0x93

0x25 0x43 0x27 0x93 0x52 0x93 = BCD 37 67 39 147 82 147.

Post by **vtl** » 25 Apr 2021, 08:10

MaxDenisov wrote: 24 Apr 2021, 12:57 @vtl I am working on new pc/hardware design. Please let me know if you are interesting in spare pcb/device

It also need a driver for K-line, for earlier P2s. I used mc33290d connected to serial port 3.

Post by **vtl** » 25 Apr 2021, 08:13

3r1k wrote: 24 Apr 2021, 17:06 I also have a bunch of P1 CEM I am more than interested into getting hacked over the canbus, rather than solder manually.

P1 works. The current github code was improved inadvertently in a way that broke it, but it turned out it can be cracked with P2 path, only shuffleOrder needs to be taken from P1.

I've got a P1 CEM, but have no free minute to hook it up.

MaxDenisov · Post by **MaxDenisov** » 25 Apr 2021, 09:02

vtl wrote: 25 Apr 2021, 08:10
MaxDenisov wrote: 24 Apr 2021, 12:57 @vtl I am working on new pc/hardware design. Please let me know if you are interesting in spare pcb/device
It also need a driver for K-line, for earlier P2s. I used mc33290d connected to serial port 3.

two in one or just separate device/adapter?