keithrfung
commented
4 years ago We're still working on confirming on this is a consistent bug. It has been difficult to replicate. Here are notes on the bug for future research.
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Attempts to replicate the bug can be done in two ways. 1) Suspend Ubuntu and awaken OR (2) wait for timeout. It feels to be about 10 min?
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Current scanner used is Honeywell MK7580-30B38-02-AN. This scanner can be set up by scanning barcodes from the manual (see link). There is discussion that certain possibilities lead this to become disabled. This also may affect whether the scans are seen as lines for the text file.
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Ubuntu is run on the machine with the scanner. That being said most modern operating systems have an "auto-suspend" feature to save power sent to USB devices. This could simply be related to this. This is a relatively common problem.
There seem to be many answers:
Using TLP , a package, seems to be a common one. TLP: https://linrunner.de/en/tlp/docs/tlp-configuration.html#usb
Here is another possibility. https://askubuntu.com/questions/1140925/how-can-i-disable-usb-autosuspend-on-ubuntu-18-04
Bug Report
Current Behavior Sometimes the barcode scanner goes idle, then when it wakes back up, it gets a new device ID from the operating system. This appears as if the scanner scans (beeps), but the cast/spoil count doesn't increment. You can reboot the device, which will fix it, but will also reset the count; or you can hop back out to the operating system and restart the background service, which will keep the count.
Expected behavior/code The scanner should either (1) stay active and therefore keep the same device ID or (2) the id should be updated without requiring the reboot.
Environment
Possible Solution Currently Unknown
Additional context/Screenshots