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No GNU licence for device creation?



  • I don't really understand if it's possible to develop a Qt-based device with an "open source license".

    The licensing page says :

    If you are developing a Qt-based device, a commercial license is recommended to embed and control Qt on your device. [...] If you do not want to share your code, leave your device “open” for external developers to alter or update your device’s functionality, you cannot use the open source licenses for device creation with Qt.

    So well... I know... We can't do proprietary stuffs with the open source licence of Qt. But that's already the case for other kind of software, not only for device creation. So what the point in saying it again?

    Then, what I understand is that if I'm OK to share my code, I may be able to use an open source license of Qt. Well... Could you tell me where to go? How can I download Qt for Device Creation or any tool to help me in building an image ? I'm a bit lost at this point.



  • What I experienced is, device creation is just like a package with Qt enterprise to let developer quickly deploy their apps onto the device. I didn't see any device creation for the open source license, since I usually downloaded the source code and cross-compile it for our device.

    Basically, if you can leave your device open for developers to modify the internals, you can use open source license. Or you must purchase the commercial license. Please notice that there is also a run-time fee per device you must pay in mass production stage.



  • So you need a GNU license,and if your using Qt for android,You also need an Apache license.



  • @charlycoste Hi, what I understand is that if you're developing a Qt-based device (i.e. medical monitor, automobile dashboard, wi-fi router, etc.) and you use Qt open source version, then you are obliged to share the source code of what you developed on user request. That's why they refer as "leaving the device open" to external developers. Given that you purchase a commercial license of Qt, you're relieved of sharing anything. It's your option based on what you expect about the lifecycle of your Qt-based device.

    Regarding how to get "Qt for Device Creation" I'd start by requesting a free trial, and I guess some sales representative from Qt will follow up with you.

    Good luck with your project!



  • @Pablo-J.-Rogina said:

    @charlycoste Hi, what I understand is that if you're developing a Qt-based device (i.e. medical monitor, automobile dashboard, wi-fi router, etc.) and you use Qt open source version, then you are obliged to share the source code of what you developed on user request.

    That's what I understand too... But where are we supposed to find Qt open source version for Device Creation ?
    On the Qt for Device Creation page, you can only request a Trial.

    And if you follow the Documentation for embedded link in the Quick Links list, and then have a look to Installation Guide, you can read:

    3. Installing Qt for Device Creation
    Download the binary Qt for Device Creation installer, and make sure it is executable by using one of the following methods: [...]
    

    OK... but where can I download this installer ?

    What I understand here, is that you can't use Qt for Device Creation if you didn't buy a commercial licence, no matter if you are doing an Open or a Closed project.



  • @charlycoste said in No GNU licence for device creation?:

    That's what I understand too... But where are we supposed to find Qt open-source version for Device Creation?
    On the Qt for Device Creation page, you can only request a Trial.

    Qt open-source for Device Creation does not exist. There's only one Qt open-source version. Qt for Device Creation is not really that unique. It's just the normal Qt for Application Development with additional modules, software stacks (e.g. Boot to Qt & Qt Automotive Suite) and pre-built images to make it easier to develop and deploy on Embedded devices. So this means you'll have to download the open-source version and configure it to cross-compile on the board (target device) you want. For beginners, I recommend starting out with Raspberry Pi. Here are a few resources you can use.
    https://mechatronicsblog.com/cross-compile-and-deploy-qt-5-12-for-raspberry-pi/
    https://medium.com/@amirmann/how-to-cross-compile-qt-for-raspberry-pi-3-on-linux-ubuntu-for-beginners-75acf2a078c

    Qt for Device Creation is already pre-configured and has pre-built images for several target devices. Not to mention it uses the commercial license so you don't have to release the source code. It also comes with support if you need it. But for a hobby project, I think the open-source version is okay if you're prepared to set up everything by yourself.

    Oh! Almost forgot. Qt Extended/Qtopia (a subset of Qt Embedded- I think this was also GPL at one point) was once released under the GPL license but it was discontinued back in 2009 when Nokia owned Qt. It was designed for embedded Linux-based mobile devices like the Greenphone or the Neo FreeRunner. After the discontinuation, it was forked in QtMoko but I don't think it's being developed anymore.


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