Having a very difficult time with initial setup with my brand new v3.1 500mm
I am now experiencing a -MCU 'mcu' shutdown: ADC out of range- error message. The printer will turn on, run for a second and then shut off leading to this.
I've wired everything, even making sure to correctly swap the end-stop wires. I have flashed the imager file (.xz) into the Pi4 from the RatOS setup site, even downloading and going through balenaEtcher. I used the hotspot and set up the Mainsail/RatOS on my wifi. I was able to connect. I compiled firmware from the scripts menu. It was successful. I then went into firmware_binaries. Downloading the Octopus v1.1 firmware file. Putting it onto an SD card formatted as an FAT32 with a clustersize of 8kb. Flashed the octopus. After letting it sit for a few mins. Removed the SD card. File changed from a .bin to a .CUR file. I downloaded the Vcore 3 firmware I believe it was, whatever the 3 options were I selected the printer I had. I changed all the settings in the printer.cfg file to match the items that were on my printer including changing the correct bed size.
Now, while trying to problem solve myself, I joined this discord, and I found a post in here regarding MCU connection issues.
https://discord.com/channels/582187371529764864/1046952693480038500
I've gone down the list even removing a jumper that wasn't mentioned at all in the setup. So the boards can communicate via USB cable. At this point I'm thinking I have to unwire everything and do a single plug at a time, with continuous restarts until I find the wire that is apparently, wired wrong, that causing this error.
First time doing anything like this and the frustration is mounting. A lot of the solutions I've seen thus far are like looking at a foreign language. I really want to pack it up, send it to someone with a letter that just says "PLEASE, out of the kindness of your heart, fix whatever is wrong". Currently beating my head against a metaphorical wall with this one.
40 Replies
check if your thermistor is correctly connected
the ADC out of range- error messag means that you can connect the board, but the thermistor returns a value that doesnt fit into the safety margins
hilarious-sapphire•16mo ago
My thermistor is plugged into the J45 on the octopus board as indicated in the ratrig wire diagram. It is using a dupont connector tho and not a JST connector
Is it possible that the orientation of the plugged has something to do with it? Like the plug being in flipped 180? Would this also be a massive issue, like my board now being useless?
no, the orientation doesnt matter, its jsut a resistor
but it could be the dupont connector
what about the bed thermistor?
its one fo them
put this at the end of your printer.cfg
[extruder] min_temp: -250 [heater_bed] min_temp: -250that should get you around the ADC out of range for now so you can see which one is causing the error
hilarious-sapphire•16mo ago
The bed thermistor is plugged into J44, I'm currently going to turn it all off and check the entire wiring to make sure nothing is lose or out of place.
Ok. Ill try this and see if it does anything before I start unwire tying everything.
after you update the printer.cfg file, save and restart klipper
otherwise it won't do anything
hilarious-sapphire•16mo ago
Added and it seems like it stays on for just a split second longer, probably me just trying to feel better about it. However, same issue. I'm going to take the wire ties off. Follow everything and make sure its all actually plugged into each other.
what is the error you are getting?
cause that should work even if your temp probes aren't attached
hilarious-sapphire•16mo ago
Klipper reports: SHUTDOWN
MCU 'mcu' shutdown: ADC out of range
This generally occurs when a heater temperature exceeds
its configured min_temp or max_temp.
Once the underlying issue is corrected, use the
"FIRMWARE_RESTART" command to reset the firmware, reload the
config, and restart the host software.
Printer is shutdown
please share your printer.cfg and the klipper.log
as files, drag and drop them into this window
hilarious-sapphire•16mo ago
looks like your extruder is reporting over 400 degrees
is it actually heating up when you are turning your printer on?
hilarious-sapphire•16mo ago
From what I can tell, I don't think it stays on long enough for any noticeable change. Currently with it being in the shutdown state with everything technically still powered it is cold, no radiant heat coming from it at all.
I can even touch the tip of the nozzle and its cold
you dont set the sensor type in your printer.cfg
isn't that set in the Revo include?
line 109
the max chip config?
ups, sorry
wrong thread
mixed up two threads 
well safety wise that is good
so might just mean that your hotend is broken
hilarious-sapphire•16mo ago
Ok going of this, would the Revo setup line be the wrong setup with a Revo Voron Rapidchange? It was brand new out the box ðŸ˜
not sure, never heard of that one
it still can be the connector or a shortcut you cant see
does it use a
ATC Semitec 104NT-4-R025H42G?
though if that was the case, wouldn't it be reporting a negative temp instead of 400+?yeah, its a long shot, but i would control it anyway
or he switched the hotend and bed thermistor cables
the logs are showing 16ish degrees for the bed
hilarious-sapphire•16mo ago
Is that the connector type? Off the E3D site it says its a E-Semtec-50-molex
so, seems like that one is working correctly
https://github.com/Rat-OS/RatOS-configuration/blob/master/hotends/revo.cfg#L10
it's the sensor type
hilarious-sapphire•16mo ago
off the E3D site it says that, that is indeed the sensor.
Semitec 104NT-4-R025H42G
well, wherever you bought it from - I would ask for a refund
hilarious-sapphire•16mo ago
So basically my best bet right now is to just follow the thermistor wires for both the bed and hotend and make sure everything is plugged in. If it appears to be all connected. Contact my supplier and see about sending this one back and getting a new one.
I would just disconnect your hotend thermistor connection. It should change from reporting 400+ degrees to a negative value
if it doesn't, then maybe you connected the thermistor to the wrong port
hilarious-sapphire•16mo ago
That would be checked somewhere in the Klipper downloaded log file, correct?
If I'm reading the log correctly, I have unplugged the thermistor for the hotend and it is still reading over 440 degrees. I have definitely screwed something up. Unless I have to restart it all for it to refresh the log. Ill try that, see what it says but regardless, I think im going to retrace my hotend thermistor wires and make sure they are all plugged in correctly.
I hope you unplugged it while it was turned off?
hilarious-sapphire•16mo ago
Yes.
Then yeah that's not normal, it should be reading a negative temperature when nothing is attached
hilarious-sapphire•16mo ago
I restarted it. It is now running, like it used to with the fan at 100%, however I cant seem to connect to mainsail/RatOS now. So I think I have to go back to the hotspot and reset it up again.
Fan is on because it thinks your hotend is hot
Try commenting out your hotend on line 109 and choose a regular V6 so that it is configured for a different thermistor type
hilarious-sapphire•16mo ago
Hotend fan is off, which used to be on. Its the part cooling fan that is running. Which always ran. on restart. I'm going to take a break from this, there is something I have to do, but I will, turn off unplug EVERYTHING associated with the hotend assembly and make sure it was all wired correctly.
Then come back with an update.
Good luck!
hilarious-sapphire•16mo ago
I'd like to thank you both for your time and effort into this.
Well, I'm a dumb dumb. Somewhere down the line of labeling things and terminating them. This happened. So this issue is resolved again, thank you for your time and effort. It really does mean a lot. Now to continue the process until I hit another wall with either not understanding something or doing something wrong. Hopefully wont be back anytime too soon in one of these threads. 😅
it was the hotend thermistor and the heating cables from the hotend btw. Still close enough.