Awesome! Thank you!!!
There is a place for it on the 36. on the left side there is a white connector that is for endstops. PC13, PC14, PC15
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Thanks I don’t know how I didn’t see it before. Going to blame it on being tired lol.
Man this CAN is kicking my BUTT!!! Finding documentation that doesn’t expect you to already know what to do is a real pain. I did find one great guide but now its led me to a dead end and I have no idea what to do LOL
@probrwr @azab2c or anyone else with CAN experience. Running into an issue that I cant figure out. I have added the file to create can0 on the pi and done a reboot but it still says can0 doesn’t exist. I can use WinSP and see the file there but the pi wont use it. I’m at a loss. I think once I figure this out ill be back on track but who knows LOL. I’ve made a post on the klipper forum as well.
Don’t recall the details, still thinking… This was a while back, and I probably drank a fair bit since then to work through the trauma from setting up CAN bus, my Klipper forum topic troubleshooting broken/hung (?) EBB36.
Captured and shared my Klipper with CanBus notes (more scraps, than a guide) at v1engineering-mods/mp3dp-v4/sw-klipper-with-canbus.md at main · aaronse/v1engineering-mods · GitHub
Looks like folks on the forum would appreciate a klippy.log Cannot Create Can0 Network - General Discussion - Klipper, something useful in the content of that file?
I did not do this as a separate Pi but with a Manta board. I do recall that the can bus is on the board so you enable it by making the klipper file for your board. It was CAN over USB i think.
If you scan through my posts on my build I list the resources I used. MP3DP V4 Build - SW Virginia - #80 by probrwr
I got some help from discord this morning and got past a lot of stuff to get all the way to here…
Looks like I got the same board @azab2c got lol. Swapping it now. A Google search for the problem lead me straight to your post on the klipper forum lol
Just installed the new one and it did the same thing with the dim light. Went ahead and flashed it anyways to see what would happen, this time I turned on the status led light to see if I would get can communication and that’s flashing like it should but I still cant get a uuid from it.
Don’t feel bad. I spent 30 minutes trying to get a new ESP32 DEV board with built-in TFT working… only to finally figure out that the TFT had a backlight that I wasn’t turning on 
I guess both of my EBB36 are DOA. I don’t get it though. They both flashed just fine. The second one I turned on the status light and it blinked on and off just like it should. But nothing I do will get me a UUID. Just ordered a 3rd to see if I can get one to finally work LOL
On and off every second or so, this one is definitely functioning, probably. Double check baud rates match. Anything in the klippy.log? Vaguely recall needing to check/fix my can bus wiring.
I just built a second cable and triple checked it with my meter before hooking it up. I still cant get it. I have a U2C here and I think I’m going to try it that way but now I pretty much have to start over it seems the octopus is set up to be the can bridge currently. Man all this mess has me wanting to pull my hair out lol. it should NOT be this hard!
I attached the log to see if you see anything I might be missing.
klippy (2).zip (22.8 KB)
I got klipper flashed to the ebb36 but had to do it over usb using make flash. I should have been able to do it over can but I have to have the uuid to do that and I never could get it. doesn’t make any sense why i can flash a boot loader and firmware but I cant get a uuid from it.
Come to find out the problem wasnt with the ebb36 after all. I hooked it up to a U2C and had just it hooked to the Pi and I got a uuid from it. So its communicating. Tried to start over and reflash everything on the octopus and I think its bricked. Keep getting this error…
I am thinking there is a way to reflash the stock bootloader and fix it but I haven’t been successful with that yet. The first guide I followed had me use STM32 to flash the canboot and I think that’s where things went wrong. The more I look around since then no other guide mentions using that. But I have come across mentions of being able to use it to fix a bricked board but no one explaining how lol.
Well I finally got it moving today!!! And with Canbus to the toolhead!!! Wasn’t the way I set out to do it but I did get it done lol.
I’m pretty sure I bricked the Octopus board. But I do believe there is a way to fix it I just didn’t have the patients to go down that road right now. Leave that for another day lol.
What I ended up doing was going back to the SKR Pro 1.2 and using a U2C. And that worked great! Its amazing how much stuff you can hook up on this little board and run over just 4 wires!
Now I need to put some plastic though it and do some tuning and get it actually printing again!
So what’s the verdict?
Was it worth the trouble? How much did the CAN actually save you wiring-wise?
Do you have before and after pictures?
Asking for a friend… 
Congrats @Jonathjon! Shame about your Octopus board. Worth the PITA to setup?
Some MP3DP wiring examples, mostly not CAN based…
I went from a total of 22(ish) wires going to the toolhead down to 4 so I would say its worth it. Plus as much as it aggravates me sometimes I do enjoy learning. Can is a PITA though because there is no good info out there. And the guys that know it don’t like to tell you lol. They want to give real short simple answers like you already know. I did end up finding what I think would be a really good guide but I had already followed a bad guide by that point and messed up the octopus. It would have been nice to have that and not needed the U2C along with it.
Once I see how it goes printing with it we will see if I will update any other printers to it. I’m suspecting that I will.
Also one thing that tripped me up is CanBoot is not called CanBoot anymore, its now katapult. So that changes a few name things and can mess up the install
HAHAHA Not gonna happen at this point. My wiring is a wreck!
Crap. Curious which guide(s) you recommend avoiding, and/or using? I want to update my shared notes to not cause unnecessary suffering.
The EBB36 sure has a lot going on.
fwiw ended up buying but not needing a U2C too, missed the return window. So, the U2C’s just sitting in some container as evidence of poor planning.
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I tried to upload the one I think is good but the file is too large. I got it from a facebook group I joined yesterday. “BIGTREETECH (BTT) Octopus Owners Group”
The one I originally followed that led me to brick the board was this word document. I dont have the link anymore. Tried to upload it but its too large.