Your Trinkey should now be set up to type the contents of QR codes into your computer! To test it, go to a site like qr-code-generator.com and type in some text. A QR code should be displayed, and if you create a blank document in a text editor and give it keyboard focus, when you show the QR code to the Tiny Code Reader you should see the contents get typed in.

Going Further

The great thing about QR codes is that you can use them to share any short text strings without needing a special app, since they're just images that can be printed out, emailed, or texted. This means that if you have information you want to input into your project, but don't want to include a keyboard in your system, a TCR can be a helpful alternative. The full developer guide has more examples, but here are some suggested use cases.

WiFi Provisioning

On Android, you can just go to WiFi settings, choose share, and it will display a QR code containing the name and password of the network you're currently connected to. It's also possible to do the same thing on iOS but it's a bit more fiddly. If you have a project that you want to connect to WiFi without reflashing or using a keyboard, you can read these QR codes to extract the network name and password. This can be extended to may different kinds of configuration, as long as the information fits in a short text string.

Access Control

Instead of using a keypad with a PIN code to lock a box or door, why not use a password saved in a QR code? You can have a much longer secret since users don't have to remember it, and even multiple different passwords with different access levels. For example, you could program a door lock with a code that only works on a particular day between 9am and 5pm if you wanted to give a contractor temporary access.

E-ink Badges and Displays

E-ink displays are great because they don't use any power to maintain a picture. This makes them ideal for things like conference badges, price labels, or meeting room names, since the contents don't need to change frequently and so a device can run for months or years on a small battery. It's not always easy to update them though, since network protocols like Bluetooth or WiFi require extra hardware and fiddly setup to connect, and a keyboard won't fit the form factor.

Adding a Tiny Code Reader that's triggered on a button press makes it easy to update displays with new information, since the process just involves creating a QR code with the text you want and pressing a button to scan it. This Badger RP2040 project shows one way of doing that. Even better, e-ink displays are great at displaying QR codes too, so it's even possible to share information between devices by scanning displays, for example to share contact information from a conference badge.