QL-800 red blinking light on print

[every-coin-online]

I didn't change anything in my environment, although I did a general update after I got this error. Ubuntu 20.04.6 LTS, can't work it out. Was working for a year prior to this. (Great app, thank you saves a lot of time).

[FriedrichFroebel]

Is there anything shown in the terminal? Did you choose the correct printer type and connection? Is the Editor Lite mode disabled?

[every-coin-online]

Hi, thank you for your response.

Terminal shows:

127.0.0.1 - - [02/May/2023 08:37:41] "POST /api/print/text HTTP/1.1" 200 17

The config.json file is as follows:

{
"SERVER": {
"PORT": 8013,
"HOST": "",
"LOGLEVEL": "WARNING",
"ADDITIONAL_FONT_FOLDER": false
},
"PRINTER": {
"MODEL": "QL-800",
"PRINTER": "file:///dev/usb/lp0"
},
"LABEL": {
"DEFAULT_SIZE": "62",
"DEFAULT_ORIENTATION": "standard",
"DEFAULT_FONT_SIZE": 70,
"DEFAULT_FONTS": [
{"family": "Minion Pro", "style": "Semibold"},
{"family": "Linux Libertine", "style": "Regular"},
{"family": "DejaVu Serif", "style": "Book"}
]
},
"WEBSITE": {
"HTML_TITLE": "Label Designer",
"PAGE_TITLE": "Brother QL Label Designer",
"PAGE_HEADLINE": "Design your label and print it…"
}
}

Editor Lite mode is disabled by default when I turn the printer on. If I turn it on and try to print, I get this in the terminal:

127.0.0.1 - - [02/May/2023 08:36:42] "POST /api/print/text HTTP/1.1" 200 17
WARNING:main:Exception happened: [Errno 2] No such file or directory: '/dev/usb/lp0'
127.0.0.1 -

[FriedrichFroebel]

This usually indicates that your USB port has changed or the udev rule is missing. What does ls -l /dev/usb show?

[every-coin-online]

Thank you for your help.

ls -l /dev/usb shows:
total 0
crw-rw---- 1 root lp 180, 0 May 3 07:32 lp0

[FriedrichFroebel]

Are your udev rules for the printer still intact? Id est, do you have any Brother-specific rules in /etc/udev/rules.d/ which match your device?

Example: File /etc/udev/rules.d/69-brotherql-labelprinter.rules with the content

# udev rules for Brother QL label printers using usb

# Source: https://github.com/pklaus/brother_ql/issues/121
# Get IDs with `lsusb`.
# Installation:
# - Copy this file to /etc/udev/rules.d/
# - Run the command:
#       udevadm control --reload && udevadm trigger

ACTION!="add|change", GOTO="brotherql_rules_end"
SUBSYSTEM!="usb|usbmisc", GOTO="brotherql_rules_end"

# QL-800
ATTRS{idVendor}=="04f9", ATTRS{idProduct}=="209b", TAG+="uaccess"

LABEL="brotherql_rules_end"

[every-coin-online]

Hi, 69-brotherql-labelprinter.rules was not there. I created it with the code above, same issue - blinking red light.

how do I check idVendor and idProduct values? Is that even the issue?

[FriedrichFroebel]

Did you trigger a reload for the rules, for example by rebooting the Ubuntu device?

[every-coin-online]

I don't believe this file reappears after a reload. I've restarted the desktop this Ubuntu instance is on several times since the issue manifested.