- Built the (shitposty) #USB2Speakon adapter
- Designed a new revision of the #SSD1303 breakout PCB
- Developed a small ESP-NOW telemetry and logging framework for a model rocket #jfzhn project
- Finished reverse engineering the #startergenerator. It spins now! \o/
- Built #TheLAEMPAN together with @techbeard and @Toble_Miner (RGB replacement PCBs for IKEA LAMPANs, more info coming sometime™)

#GoodOf2024 2/3

The general control loop is also pretty impressive, the engineers at #Bosch SEG definitely did their job well.

The lowest limit I can set is 6 RPM and it runs buttery smooth.

And it has insane amounts of torque. If you hold the pulley really tightly, it slips out of most strong hands at around 6-7 Nm (as reported via the CAN status messages).

This will be really fun once put into some small vehicle :D

(It can also recuperate really well, but can't run in reverse at all)

We also did a max RPM test of the #startergenerator using one of @patagona's rescued Pylontech batteries, because the 20A of my 1kW lab PSU weren't enough :D

I set the torque limit to 0.7 Nm (out of 55), no RPM limit and let it rip :D
It reached a peak of 43A (~2kW) at the end of the acceleration, settled at 25A (~1.2kW) and reached a peak RPM of 13400.

It was a bit scary tbh :D
(Not sure if the video accurately captured the sound it made)

(Pylontech thread: https://chaos.social/@patagona/113149877881417810 )

There's still a lot left to do.
I need to implement the #XCP stuff into the STM32 firmware, so it can run the #startergenerator stand-alone.
Stuff like:
- Checking the firmware version on the ECU, so it doesn't poke the wrong memory address
- Reading and parsing the status of the motor
- And actually controlling the motor properly instead of just sending it a hardcoded 1 Nm torque request :D

And then also cleaning it up enough, documenting and testing it thoroughly, so it can be published.

I spent many dozens of hours losing track of time in #Ghidra (I swear, it's worse than #Factorio)

Until I had figured out the #CAN message handling, signal parsing and where and when which #DTC codes get set.
With that knowledge I could figure out, slowly but surely, what the #startergenerator needs to run.
Even #FBS4 was pretty trivial to circumvent (a single 1 written to the right memory location via #XCP)

And after implementing the ~25 CAN messages in my STM32 code I finally got this today:

Update time:
At the end of December I implemented most of the messages the #startergenerator wants to see.
I knew I got it right enough because the 7 DTC codes it was previously spitting out shrank to just 1. The ones that went away were something like "communication failure power train controller", but the one remaining DTC was a bit disheartening...

"P143468: Imob_E_LOCKED - The driving authorization has not been released."

- Helped @crexodon a bit with the #Unterland badge
- Quickly hacked together some Art-Net support for @twizzarak's tail
- "Fixed" the water-damaged motor #ECU of my car
- Finally got CAN communication with the #startergenerator
- @patagona and I took a look at some cheap #BK7231N based string lights and built a #ESPHome firmware
- Attended a number of repair cafés and helped repair a handful of devices
3/3

- Bought a Mercedes #startergenerator and started reverse-engineering it
- Implemented gamma correction for #PixelBridge
- Built a control board and instrument display for the #ePocketBike
- Dabbled in upholstry and built a new seat for the #ePocketBike
- Acquired some big #SSD1303 OLEDs and desgined a breakout board + Arduino library for it.
- Released the #PawConnect (Tag-Connect #TC2030 compatible f̶o̶o̶t̶ pawprint)
- Built the now famous #PDBrick together with @techbeard
2/3

Got out the #startergenerator again today.
But (destructively) removing the back cover of the #BSG revealed even less than I had feared...

Just a big welded(!) copper distribution plate and more plastic and silicon.

Only a hint of ceramic PCB can be seen through a tiny little hole, that's it.

Going any further than that really needs some effort and would very likely lead to damage of the power electronics, so I'll probably stick to the #CAN fuzzing / information digging approach for now...

Trying to send some #CAN messages to the #startergenerator didn't prove successful either.
I'm not well versed in CAN, but the dongle just kept trying to send the single message on repeat.
So I guess it didn't receive a CAN ACK?
Afaik, all transceivers in a bus should ACK a frame, no matter if they're addressed or not.

Not sure why it didn't work. Maybe I was on the wrong baud rate or this device behaves weirdly and only sends ACKs after getting a magic message?

After much digging I at least found the pinout in some Mercedes shop software.

But unsurprisingly the #startergenerator didn't send any messages on its own on the #CAN bus when hooked up to 12V.
It did draw 11 mA tho, so at least the pinout seems correct and the controller appears awake.