What is the problem?
Serial connection keeps failing. It started when we "stress-tested" the printer by pulling the serial cable from the Rpi to the printer out of the printer, and now it just won't connect, after being perfectly connected for a long time.
What did you already try to solve it?
We usually connect to the printer using the REST api, so we tried this as well as doing it manually without our API-system running.
We also monitored the htop to see if anything was out of the ordinary (as Googling' lead us to some posts where this was brought up), but nothing popped up. The htop.out is in the shared log-folder below though.
We have 8 other of the exact same printer running the exact same firmware, octoprint version as well as Raspberry version - only this one printer has the issue.
Switching out the Raspberry did "fix" the issue, but we'd very much like to figure out why this happened, so it can be avoided in the future - maybe we are doing something wrong?
Update while writing; we managed to get it connected once, but pulling the serial cable and inserting it again resulted in the same issue - all other printers can handle this just fine
The log files
The lines below is what keeps happening. It looks like it connects to the printer just fine - it receives a lot of data before suddenly saying "Connection closed"
Changing monitoring state from "Connecting" to "Offline"
Changing monitoring state from "Offline" to "Detecting serial port"
Serial port list: ['/dev/ttyUSB0']
Connecting to: /dev/ttyUSB0
Changing monitoring state from "Detecting serial port" to "Opening serial port"
Connected to: Serial<id=0x6fd340f0, open=True>(port='/dev/ttyUSB0', baudrate=115200, bytesize=8, parity='N', stopbits=1, timeout=10.0, xonxoff=False, rtscts=False, dsrdtr=False), starting monitor
Changing monitoring state from "Opening serial port" to "Connecting"
Send: N0 M110 N0*125
Send: N0 M110 N0*125
Recv: start
Send: N0 M110 N0*125
Recv: echo: External Reset
Recv: Marlin 1.0.0
Recv: echo: Last Updated: Oct 29 2016 10:22:46 | Author: (none, default config)
Recv: Compiled: Oct 29 2016
Recv: echo: Free Memory: 11431 PlannerBufferBytes: 1232
Recv: echo:Hardcoded Default Settings Loaded
Recv: echo:Steps per unit:
Recv: echo: M92 X80.00 Y80.00 Z400.00 E93.00
Recv: echo:Maximum feedrates (mm/s):
Recv: echo: M203 X500.00 Y500.00 Z5.00 E25.00
Recv: echo:Maximum Acceleration (mm/s2):
Recv: echo: M201 X500 Y500 Z100 E5000
Recv: echo:Acceleration: S=acceleration, T=retract acceleration
Recv: echo: M204 S500.00 T500.00
Recv: echo:Advanced variables: S=Min feedrate (mm/s), T=Min travel feedrate (mm/s), B=minimum segment time (ms), X=maximum XY jerk (mm/s), Z=maximum Z jerk (mm/s), E=maximum E jerk (mm/s)
Recv: echo: M205 S0.00 T0.00 B20000 X20.00 Z0.40 E5.00
Recv: echo:Home offset (mm):
Recv: echo: M206 X0.00 Y0.00 Z0.00
Recv: echo:PID settings:
Recv: echo: M301 P21.73 I1.54 D76.55
Connection closed, closing down monitor
Full logs;
Additional information about your setup
OctoPrint 1.3.12 running on OctoPi 0.15.1 - Raspberry Pi 3B
