Octoprint disconnect error mid print, Anycubic Kobra Neo

What is the problem?

My printer keeps disconnecting mid print, with the error "Unexpected error while reading serial port, please consult octoprint.log for details: SerialException: 'device reports readiness to read but returned no data (device disconnected or multiple access on port?)'"

What did you already try to solve it?

  • Changed cables (just ordered new ones and will test that tomorrow)
  • Updated Octoprint
  • Turned off and on the printer and raspberry pi zero 2 w many times

Here is the what the serial log shows:

2024-02-21 20:45:17,656 - Unexpected error while reading serial port, please consult octoprint.log for details: SerialException: 'device reports readiness to read but returned no data (device disconnected or multiple access on port?)' @ comm.py:_readline:4158
2024-02-21 20:45:17,738 - Please see https://faq.octoprint.org/serialerror for possible reasons of this.
2024-02-21 20:45:17,776 - Changing monitoring state from "Printing" to "Offline after error"
2024-02-21 20:45:17,833 - Connection closed, closing down monitor
2024-02-22 00:11:29,435 - Changing monitoring state from "Offline" to "Opening serial connection"
2024-02-22 00:11:29,456 - Connecting to port /dev/ttyUSB0, baudrate 115200
2024-02-22 00:11:29,545 - Changing monitoring state from "Opening serial connection" to "Connecting"
2024-02-22 00:11:29,554 - Connected to: Serial<id=0x707a9760, open=True>(port='/dev/ttyUSB0', baudrate=115200, bytesize=8, parity='N', stopbits=1, timeout=10.0, xonxoff=False, rtscts=False, dsrdtr=False), starting monitor
2024-02-22 00:11:29,570 - Send: N0 M110 N0*125
2024-02-22 00:11:29,620 - Recv: echo:Unknown command: "q9ÿçGfÿÿ–ÿGN0 M110 N0"
2024-02-22 00:11:29,625 - Recv: ok
2024-02-22 00:11:29,634 - Send: N0 M110 N0*125
2024-02-22 00:11:29,677 - Changing monitoring state from "Connecting" to "Operational"
2024-02-22 00:11:29,730 - Recv: ok
2024-02-22 00:11:29,743 - Send: N0 M110 N0*125
2024-02-22 00:11:29,778 - Recv: ok
2024-02-22 00:11:29,784 - Send: N1 M115*39
2024-02-22 00:11:29,834 - Recv: FIRMWARE_NAME:Marlin bugfix-2.0.x (Sep  9 2022 14:01:11) SOURCE_CODE_URL:github.com/MarlinFirmware/Marlin PROTOCOL_VERSION:1.0 MACHINE_TYPE:Anycubic Kobra Neo EXTRUDER_COUNT:1 UUID:cede2a2f-41a2-4748-9b12-c55c62f367ff
2024-02-22 00:11:29,873 - 
2024-02-22 00:11:29,883 - ---------------------------------------------------------------------------
2024-02-22 00:11:29,924 - Your printer's firmware is a development build of Marlin (build date
2024-02-22 00:11:29,924 - 20220909). It might be more unstable than a release version and should be
2024-02-22 00:11:29,924 - kept up-to-date.
2024-02-22 00:11:29,924 - 
2024-02-22 00:11:29,925 - Learn more at https://faq.octoprint.org/warning-firmware-development
2024-02-22 00:11:29,925 - ---------------------------------------------------------------------------
2024-02-22 00:11:29,925 - 
2024-02-22 00:11:29,925 - 
2024-02-22 00:11:29,984 - Recv: Cap:SERIAL_XON_XOFF:0
2024-02-22 00:11:29,997 - Recv: Cap:BINARY_FILE_TRANSFER:0
2024-02-22 00:11:30,039 - Recv: Cap:EEPROM:1
2024-02-22 00:11:30,043 - Recv: Cap:VOLUMETRIC:1
2024-02-22 00:11:30,049 - Recv: Cap:AUTOREPORT_TEMP:1
2024-02-22 00:11:30,074 - Recv: Cap:PROGRESS:0
2024-02-22 00:11:30,092 - Recv: Cap:PRINT_JOB:1
2024-02-22 00:11:30,096 - Recv: Cap:AUTOLEVEL:1
2024-02-22 00:11:30,108 - Recv: Cap:RUNOUT:1
2024-02-22 00:11:30,115 - Recv: Cap:Z_PROBE:1
2024-02-22 00:11:30,137 - Recv: Cap:LEVELING_DATA:1
2024-02-22 00:11:30,181 - Recv: Cap:BUILD_PERCENT:0
2024-02-22 00:11:30,185 - Recv: Cap:SOFTWARE_POWER:0
2024-02-22 00:11:30,201 - Recv: Cap:TOGGLE_LIGHTS:0
2024-02-22 00:11:30,219 - Recv: Cap:CASE_LIGHT_BRIGHTNESS:0
2024-02-22 00:11:30,225 - Recv: Cap:EMERGENCY_PARSER:1
2024-02-22 00:11:30,230 - Recv: Cap:PROMPT_SUPPORT:0
2024-02-22 00:11:30,252 - Recv: Cap:SDCARD:1
2024-02-22 00:11:30,259 - Recv: Cap:REPEAT:1
2024-02-22 00:11:30,290 - Recv: Cap:AUTOREPORT_SD_STATUS:0
2024-02-22 00:11:30,351 - Recv: Cap:LONG_FILENAME:1
2024-02-22 00:11:30,410 - Recv: Cap:THERMAL_PROTECTION:1
2024-02-22 00:11:30,416 - Recv: Cap:MOTION_MODES:0
2024-02-22 00:11:30,470 - Recv: Cap:ARCS:1
2024-02-22 00:11:30,474 - Recv: Cap:BABYSTEPPING:1
2024-02-22 00:11:30,481 - Recv: Cap:CHAMBER_TEMPERATURE:0
2024-02-22 00:11:30,489 - Recv: ok
2024-02-22 00:11:30,493 - Send: M21
2024-02-22 00:11:30,522 - Recv: echo:SD card ok
2024-02-22 00:11:30,536 - Recv: ok
2024-02-22 00:11:30,540 - Send: M155 S2
2024-02-22 00:11:30,565 - Recv: ok
2024-02-22 00:11:30,573 - Send: M20
2024-02-22 00:11:30,628 - Recv: Begin file list
2024-02-22 00:11:30,641 - Recv: AK_GPU~1.GCO 7396038
2024-02-22 00:11:30,643 - Recv: G1_X11~1.GCO 1157
2024-02-22 00:11:30,645 - Recv: End file list
2024-02-22 00:11:30,647 - Recv: ok
2024-02-22 00:11:30,661 - Send: M20
2024-02-22 00:11:30,694 - Recv: Begin file list
2024-02-22 00:11:30,707 - Recv: AK_GPU~1.GCO 7396038
2024-02-22 00:11:30,710 - Recv: G1_X11~1.GCO 1157
2024-02-22 00:11:30,712 - Recv: End file list
2024-02-22 00:11:30,713 - Recv: ok

I'm kind of new to this so any help will be appreciated, thanks!

Hello @SpeedRD !

Please never delete the template when you open a Get Help thread and stick to it.

A code snippet if of minor help.

Please try safe mode and attach the systeminfo bundle to your next post.

Also, in this case:

2024-02-22 00:11:29,883 - ---------------------------------------------------------------------------
2024-02-22 00:11:29,924 - Your printer's firmware is a development build of Marlin (build date
2024-02-22 00:11:29,924 - 20220909). It might be more unstable than a release version and should be
2024-02-22 00:11:29,924 - kept up-to-date.
2024-02-22 00:11:29,924 - 
2024-02-22 00:11:29,925 - Learn more at https://faq.octoprint.org/warning-firmware-development
2024-02-22 00:11:29,925 - ---------------------------------------------------------------------------

I recommend to instal a proper firmware.