Crash of Zebra Printer (Driver)

Hello :slight_smile:
I have some Acer ZEST Plus (Android 6.0) with Zebra MZ220 Printer attached over Bluetooth.
I made a form to Register Participants for Events and Distributions and it prints a “badge” for the participants that i can scan for follow-ups and tracebility.

Generally it works really fine BUT: after some time (like 2h), It does not print anymore, no error message.
The Printer is connected with Bluetooth but nothing happens.
Also if i disconnect and connect new, it does not work
Also if i restart the Printer Driver it does not work, restart Printer has no effect…
Only a restart of the phone helps.

Somehow it feels like an Overflow of something in Driver or phone.
Did anybody experience this as well?
How can we find a solution?

Best Regards!
Michael :slight_smile:

@W_Brunette Any idea where this code lives and how @Mic can get a good stack trace?

The sensors framework code is available here: https://github.com/opendatakit/sensorsframework

The actual “Zebra Driver” for that interfaces with the sensors framework is available in the sensordrivers repo in the folder “ZebraMzSeriesPrinter”. The repo is available here: https://github.com/opendatakit/sensordrivers

If you are using the binaries from the Google Play store then you want to use the code at the tagged location as that will correspond to the code in the Play store. You should use the tag “2.0_alpha_rev_1” for sensors framework and “ZebraPrinter_v2.0_rev_1” tag for sensordrivers (assuming the code was tagged properly).

The code head has been updated to work with some of the new functionality of the ODK 2 framework but has not been thoroughly tested and some other parts have probably fallen behind. An updated release of the sensorsframework with the revised ODK 2 architecture is due by the end of the year.

@Mic, since this is somewhat reproducible, perhaps you can capture a log when it happens? https://github.com/opendatakit/collect/wiki/Getting-ODK-Collect-logs has rough steps on how to do that.

Thanks Yaw,
I recently tested it on an Acer Tablet “Irconia Tab 10” that is also running Android 6.0 and it works.
Might be a Problem with the devices Bluetooth…
As soon as i find time i will do some Research on it with Logs and so on.

And the Zebra Printer Driver just got an update a few days ago, so it might be worth trying the update.