Original Reddit post

I bought a cheap Niimbot B1 thermal printer from AliExpress a year or so ago, and it was great. Then the provided labels ran out, I’ve replaced with third party labels, and it printed poorly. Turns out Niimbot have RFID tags on their own label spools, and if that is not detected, they throttle down the printing speed and reduce the quality. There’s lots of users affected by this, the usual workaround is to put an empty branded spool next to the printer, so that it reads the RFID tag, and allows you to use the third party spool. (I think it might only be required during label calibration). I had already thrown away the original spool, and as a matter of principle I refused to buy any more branded labels. Fast forward to today, I decided to let Fable 5.1 on xHigh (with skip permissions of course) to try and decode the binary file of the printer. It took a few hours, but it made some modifications to the binary, reflashed quite a few times, it needed feedback from me, I had to restart the printer, after each re-flash, but in the end it successfully modified the firmware which now allows me to use third party spools without any degradation. Source code and binary below, proceed at your own risk. It is only for version 5.22. If you have a different version, there should be enough info to instruct your own LLM to proceed with the same modifications. https://github.com/ThreeDaPrint/niimbot submitted by /u/penny_stokker

Originally posted by u/penny_stokker on r/ClaudeCode