No connection to printer (creality 4.2.7, marlin 2.0.7.2, usb device found) (SOLVED)

willibauer · November 23, 2020, 5:41pm

What is the problem?

well, sorry to be the 1000st to bother you with this problem...I just can't get it to connect.
The board is found ("ch341-uart converter now attached to ttyUSB0"), but the serial connection doesn't establish.
Running on a raspi 4 Model B Rev 1.2, web-interface up and running, newest operating system (octopi 0.18.0, board creality 4.2.7, marlin 2.0.7.2)

What did you already try to solve it?

3 different usb cables
with and without strip on +5v pin
reboot (pi)
safe mode
recompiled firmware (of printer) a few times
changed baud rate
tried everything on "Auto" and on manual config

Have you tried running in safe mode and if so did it solve the issue?

yes, no change

Complete Logs

octoprint.log

2020-11-23 17:15:30,718 - octoprint.server.util.sockjs - INFO - New connection from client: 2003:c9:3700:3e00:edbb:55ec:339e:bd83
2020-11-23 17:15:30,821 - octoprint.server.util.flask - INFO - Passively logging in user _admin from 2003:c9:3700:3e00:edbb:55ec:339e:bd83
2020-11-23 17:15:30,821 - octoprint.access.users - INFO - Logged in user: _admin
2020-11-23 17:15:31,951 - octoprint.server.util.sockjs - INFO - User _admin logged in on the socket from client 2003:c9:3700:3e00:edbb:55ec:339e:bd83
2020-11-23 17:15:32,613 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.178.64
2020-11-23 17:15:38,110 - octoprint.util.comm - INFO - Changing monitoring state from "Offline" to "Opening serial connection"
2020-11-23 17:15:38,112 - octoprint.util.comm - INFO - Connecting to port /dev/ttyUSB0, baudrate 115200
2020-11-23 17:15:38,149 - octoprint.util.comm - INFO - Changing monitoring state from "Opening serial connection" to "Connecting"
2020-11-23 17:16:01,496 - octoprint.util.comm - INFO - Changing monitoring state from "Connecting" to "Offline"
2020-11-23 17:16:01,506 - octoprint.plugins.action_command_notification - INFO - Notifications cleared
2020-11-23 17:16:06,977 - octoprint.util.comm - INFO - Changing monitoring state from "Offline" to "Detecting serial connection"
2020-11-23 17:16:07,006 - octoprint.util.comm - INFO - Serial detection: Performing autodetection with 1 port/baudrate candidates: /dev/ttyUSB0@115200
2020-11-23 17:16:07,006 - octoprint.util.comm - INFO - Serial detection: Trying port /dev/ttyUSB0, baudrate 115200
2020-11-23 17:16:07,007 - octoprint.util.comm - INFO - Connecting to port /dev/ttyUSB0, baudrate 115200
2020-11-23 17:16:07,047 - octoprint.util.comm - INFO - Serial detection: Handshake attempt #1 with timeout 2.0s
2020-11-23 17:16:07,050 - octoprint.util.comm - INFO - M110 detected, setting current line number to 0
2020-11-23 17:16:09,052 - octoprint.util.comm - INFO - Serial detection: Handshake attempt #2 with timeout 2.0s
2020-11-23 17:16:09,058 - octoprint.util.comm - INFO - M110 detected, setting current line number to 0
2020-11-23 17:16:11,060 - octoprint.util.comm - INFO - Serial detection: Handshake attempt #3 with timeout 2.0s
2020-11-23 17:16:11,065 - octoprint.util.comm - INFO - M110 detected, setting current line number to 0
2020-11-23 17:16:13,068 - octoprint.util.comm - INFO - Changing monitoring state from "Detecting serial connection" to "Error: No more candidates to test, and no working port/baudrate combination detected."
2020-11-23 17:16:13,110 - octoprint.util.comm - INFO - Changing monitoring state from "Error: No more candidates to test, and no working port/baudrate combination detected." to "Offline (Error: No more candidates to test, and no working port/baudrate combination detected.)"
2020-11-23 17:16:13,152 - octoprint.plugins.action_command_notification - INFO - Notifications cleared
2020-11-23 17:16:13,261 - octoprint.plugins.tracking - INFO - Sent tracking event commerror_autodetect, payload: {'commerror_text': 'No more candidates to test, and no working port/baudrate combination detected.'}
2020-11-23 17:30:18,507 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2020-11-23 17:30:22,651 - octoprint.plugins.tracking - INFO - Sent tracking event ping, payload: {'octoprint_uptime': 904}

serial.log

2020-11-23 17:32:17,361 - Enabling serial logging
2020-11-23 17:32:21,786 - Changing monitoring state from "Offline" to "Detecting serial connection"
2020-11-23 17:32:21,813 - Performing autodetection with 1 port/baudrate candidates: /dev/ttyUSB0@115200
2020-11-23 17:32:21,814 - Trying port /dev/ttyUSB0, baudrate 115200
2020-11-23 17:32:21,815 - Connecting to port /dev/ttyUSB0, baudrate 115200
2020-11-23 17:32:21,866 - Handshake attempt #1 with timeout 2.0s
2020-11-23 17:32:21,868 - Connected to: Serial<id=0x7f92eb2a58, open=True>(port='/dev/ttyUSB0', baudrate=115200, bytesize=8, parity='N', stopbits=1, timeout=2.0, xonxoff=False, rtscts=False, dsrdtr=False), starting monitor
2020-11-23 17:32:21,869 - Send: N0 M110 N0*125
2020-11-23 17:32:23,872 - Handshake attempt #2 with timeout 2.0s
2020-11-23 17:32:23,886 - Send: N0 M110 N0*125
2020-11-23 17:32:25,887 - Handshake attempt #3 with timeout 2.0s
2020-11-23 17:32:25,903 - Send: N0 M110 N0*125
2020-11-23 17:32:27,908 - Changing monitoring state from "Detecting serial connection" to "Error: No more candidates to test, and no working port/baudrate combination detected."
2020-11-23 17:32:27,952 - Changing monitoring state from "Error: No more candidates to test, and no working port/baudrate combination detected." to "Offline (Error: No more candidates to test, and no working port/baudrate combination detected.)"
2020-11-23 17:32:27,960 - Connection closed, closing down monitor
2020-11-23 17:32:37,395 - Changing monitoring state from "Offline" to "Detecting serial connection"
2020-11-23 17:32:37,397 - Performing autodetection with 7 port/baudrate candidates: /dev/ttyUSB0@115200, /dev/ttyUSB0@250000, /dev/ttyUSB0@230400, /dev/ttyUSB0@57600, /dev/ttyUSB0@38400, /dev/ttyUSB0@19200, /dev/ttyUSB0@9600
2020-11-23 17:32:37,397 - Trying port /dev/ttyUSB0, baudrate 115200
2020-11-23 17:32:37,398 - Connecting to port /dev/ttyUSB0, baudrate 115200
2020-11-23 17:32:37,434 - Handshake attempt #1 with timeout 2.0s
2020-11-23 17:32:37,437 - Connected to: Serial<id=0x7f92d1d5c0, open=True>(port='/dev/ttyUSB0', baudrate=115200, bytesize=8, parity='N', stopbits=1, timeout=2.0, xonxoff=False, rtscts=False, dsrdtr=False), starting monitor
2020-11-23 17:32:37,438 - Send: N0 M110 N0*125
2020-11-23 17:32:39,441 - Handshake attempt #2 with timeout 2.0s
2020-11-23 17:32:39,447 - Send: N0 M110 N0*125
2020-11-23 17:32:41,449 - Handshake attempt #3 with timeout 2.0s
2020-11-23 17:32:41,455 - Send: N0 M110 N0*125
2020-11-23 17:32:43,458 - Trying port /dev/ttyUSB0, baudrate 250000
2020-11-23 17:32:43,467 - Handshake attempt #1 with timeout 2.0s
2020-11-23 17:32:43,477 - Send: N0 M110 N0*125
2020-11-23 17:32:45,479 - Handshake attempt #2 with timeout 2.0s
2020-11-23 17:32:45,491 - Send: N0 M110 N0*125
2020-11-23 17:32:47,492 - Handshake attempt #3 with timeout 2.0s
2020-11-23 17:32:47,504 - Send: N0 M110 N0*125
2020-11-23 17:32:49,502 - Trying port /dev/ttyUSB0, baudrate 230400
2020-11-23 17:32:49,506 - Handshake attempt #1 with timeout 2.0s
2020-11-23 17:32:49,516 - Send: N0 M110 N0*125
2020-11-23 17:32:51,518 - Handshake attempt #2 with timeout 2.0s
2020-11-23 17:32:51,531 - Send: N0 M110 N0*125
2020-11-23 17:32:53,532 - Handshake attempt #3 with timeout 2.0s
2020-11-23 17:32:53,545 - Send: N0 M110 N0*125
2020-11-23 17:32:55,546 - Trying port /dev/ttyUSB0, baudrate 57600
2020-11-23 17:32:55,549 - Handshake attempt #1 with timeout 2.0s
2020-11-23 17:32:55,563 - Send: N0 M110 N0*125
2020-11-23 17:32:57,559 - Handshake attempt #2 with timeout 2.0s
2020-11-23 17:32:57,572 - Send: N0 M110 N0*125
2020-11-23 17:32:59,573 - Handshake attempt #3 with timeout 2.0s
2020-11-23 17:32:59,586 - Send: N0 M110 N0*125
2020-11-23 17:33:01,587 - Trying port /dev/ttyUSB0, baudrate 38400
2020-11-23 17:33:01,591 - Handshake attempt #1 with timeout 2.0s
2020-11-23 17:33:01,605 - Send: N0 M110 N0*125
2020-11-23 17:33:03,601 - Handshake attempt #2 with timeout 2.0s
2020-11-23 17:33:03,611 - Send: N0 M110 N0*125
2020-11-23 17:33:05,612 - Handshake attempt #3 with timeout 2.0s
2020-11-23 17:33:05,627 - Send: N0 M110 N0*125
2020-11-23 17:33:07,628 - Trying port /dev/ttyUSB0, baudrate 19200
2020-11-23 17:33:07,631 - Handshake attempt #1 with timeout 2.0s
2020-11-23 17:33:07,645 - Send: N0 M110 N0*125
2020-11-23 17:33:09,638 - Handshake attempt #2 with timeout 2.0s
2020-11-23 17:33:09,652 - Send: N0 M110 N0*125
2020-11-23 17:33:11,647 - Handshake attempt #3 with timeout 2.0s
2020-11-23 17:33:11,660 - Send: N0 M110 N0*125
2020-11-23 17:33:13,658 - Trying port /dev/ttyUSB0, baudrate 9600
2020-11-23 17:33:13,661 - Handshake attempt #1 with timeout 2.0s
2020-11-23 17:33:13,671 - Send: N0 M110 N0*125
2020-11-23 17:33:15,667 - Handshake attempt #2 with timeout 2.0s
2020-11-23 17:33:15,680 - Send: N0 M110 N0*125
2020-11-23 17:33:17,675 - Handshake attempt #3 with timeout 2.0s
2020-11-23 17:33:17,687 - Send: N0 M110 N0*125
2020-11-23 17:33:19,684 - Changing monitoring state from "Detecting serial connection" to "Error: No more candidates to test, and no working port/baudrate combination detected."
2020-11-23 17:33:19,724 - Changing monitoring state from "Error: No more candidates to test, and no working port/baudrate combination detected." to "Offline (Error: No more candidates to test, and no working port/baudrate combination detected.)"
2020-11-23 17:33:19,728 - Connection closed, closing down monitor

dmesg

[ 4884.376958] ch341 1-1.1:1.0: device disconnected
[ 6925.460607] usb 1-1.1: new full-speed USB device number 7 using xhci_hcd
[ 6925.566799] usb 1-1.1: New USB device found, idVendor=1a86, idProduct=7523, bcdDevice= 2.64
[ 6925.566816] usb 1-1.1: New USB device strings: Mfr=0, Product=2, SerialNumber=0
[ 6925.566828] usb 1-1.1: Product: USB Serial
[ 6925.575579] ch341 1-1.1:1.0: ch341-uart converter detected
[ 6925.581016] usb 1-1.1: ch341-uart converter now attached to ttyUSB0

I know this is coming up all the time, anyhow I'd really appreciate a hint or an idea to solve this. Hope I didn't forget anything necessary - if any other info is needed, I will provide (if I can).

edit: sorry for the ugly logs, I tried to put them in with scrollbars, but I don't know how ..

Ewald_Ikemann · November 23, 2020, 8:03pm

Hello @willibauer!

You can use the </> icon in the editor bar.

PrintedWeezl · November 23, 2020, 8:17pm

fixed it for you

did you configure the serial ports like this?


/**
 * Select the serial port on the board to use for communication with the host.
 * This allows the connection of wireless adapters (for instance) to non-default port pins.
 * Serial port -1 is the USB emulated serial port, if available.
 * Note: The first serial port (-1 or 0) will always be used by the Arduino bootloader.
 *
 * :[-1, 0, 1, 2, 3, 4, 5, 6, 7]
 */
#define SERIAL_PORT 1

/**
 * Select a secondary serial port on the board to use for communication with the host.
 * Currently Ethernet (-2) is only supported on Teensy 4.1 boards.
 * :[-2, -1, 0, 1, 2, 3, 4, 5, 6, 7]
 */
#define SERIAL_PORT_2 3

willibauer · November 23, 2020, 8:37pm

did you configure the serial ports like this?

geez...that did it. Damn I seem to be a noob still.
I really struggle with those pins and stuff, I just don't understand it. Is it always 1+3 or was it a blind shot? I tried before to find the right pins to control the fans, but it didn't work. This seems to be so much common knowledge that it isn't documented anywhere...or maybe it is, and I don't understand it...

Many thanks in either case, great support!

PrintedWeezl · November 23, 2020, 9:22pm

I looked it up in the example config for your board in the Marlin github repo

github.com

MarlinFirmware/Configurations/blob/08a01020b38035889757fb90c6006400946fe229/config/examples/Creality/Ender-3 V2/Configuration.h

/**
 * Marlin 3D Printer Firmware
 * Copyright (c) 2020 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
 *
 * Based on Sprinter and grbl.
 * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <https://www.gnu.org/licenses/>.
 *

This file has been truncated. show original

You're welcome
Happy printing

willibauer · November 24, 2020, 6:51am

again - learned something new. Didn't even know that exists.
Thanks!

Kapik · December 16, 2020, 7:48pm

Hi !
This solution does not work for me.
I have same logs:

Changing monitoring state from "Offline" to "Detecting serial connection"
Performing autodetection with 0 port/baudrate candidates: 
Changing monitoring state from "Detecting serial connection" to "Error: No more candidates to test, and no working port/baudrate combination detected."
Changing monitoring state from "Error: No more candidates to test, and no working port/baudrate combination detected." to "Offline (Error: No more candidates to test, and no working port/baudrate combination detected.)"

I've just tried to change Marlin's configuration with the SERIAL_PORT but without success.
Do you have any suggestion ?

willibauer · December 16, 2020, 8:08pm

Same board?
for me it works with 250000 baud with the pins configured as written above.
maybe a bad cable?