henrik-muehe

Controlling the Brother P-Touch Cube label maker from a computer

The Brother PTP300BT label maker is intended to be controlled using the official Brother P-Touch Design & Print iOS/Android app. The app has arbitrary limits on what you can print (1 text object and up to 3 preset icons), so I thought it would be a fun challenge to reverse engineer the protocol to print whatever I wanted.

Python code at the bottom if you want to skip the fine details.

Process

Intitially I had a quick peek at the Android APK to see if there was any useful information inside. The code that handles the communication with the printer in Print&Design turned out to be a native library, but the app clearly prepares a bitmap image and passes it to this native library for printing. Bitmaps are definitely something we can work with.

henrik-muehe

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# Fake a fuse install
RUN apt-get install libfuse2
RUN cd /tmp ; apt-get download fuse
RUN cd /tmp ; dpkg-deb -x fuse_* .
RUN cd /tmp ; dpkg-deb -e fuse_*
RUN cd /tmp ; rm fuse_*.deb
RUN cd /tmp ; echo -en '#!/bin/bash\nexit 0\n' > DEBIAN/postinst
RUN cd /tmp ; dpkg-deb -b . /fuse.deb