6.6 KiB
flipperzero-qrcode
Display qrcodes on the Flipper Zero
Download
Grab the latest qrcode.fap from Releases.
Installation
Copy the qrcode.fap file onto your Flipper Zero sd card in the apps/Tools
directory. Then create a top level directory called qrcodes to store your
qrcode files. This can be done using qFlipper, for example, by
draging-and-dropping qrcode.fap into apps/Tools and then navigating back to
the top level (where the directories like infrared and nfc live), right
click, and create a new folder called qrcodes.
Creating QR Codes
qrcode files are simple text files with the extension .qrcode. This app will
expect them to live in a top-level directory on your sd card called qrcodes.
They should have the following content:
Filetype: QRCode
Version: 0
Message: your content here
Message Format
qrcodes support 4 formats called "modes": numeric, alpha-numeric, binary, and kanji. Because of the limited screen real-estate on the Flipper Zero, you'll want to pick the best mode for the data you are trying to display.
The app will automatically detect the best mode to use, so the only thing you need to do is make sure the message in your file is formatted to use the best mode. For example, if your message is entirely numeric, make sure you don't include any extraneous punctuation in your file. If you're only encoding a domain name, make sure it's uppercase to take advantage of alpha-numeric mode, etc.
Numeric Mode
Consists of only numbers, nothing else. This mode can encode the most data.
Alpha-Numeric Mode
This mode can encode numbers, uppercase letters only, spaces, and the
following symbols: $%*+-./:. This format may be appropriate for urls, as
long as you're only encoding the domain name and you remember to use uppercase
letters (ex: HTTP://EXAMPLE.COM). If your url includes some path after the
domain, you'll likely need to use binary mode because the paths are usually
case-sensitive.
A qrcode in alpha-numeric mode can encode ~40% less data than numeric mode.
Binary Mode
This mode is a little bit of a misnomer: binary mode simply means that the message will be encoded as 8-bit bytes. The qrcode standard stipulates that text will use ISO-8859-1 (also known as Latin-1) encoding, not utf8 as would be the standard these days. However, some readers may automatically detect utf8. To be standard-compliant, that basically means you can only use Latin letters, numbers, and symbols.
A qrcode in binary mode can encode ~60% less data than numeric mode, and ~30% less than alpha-numeric.
Kanji Mode
This mode is unsupported, so I won't go into detail. A limitation of the underlying qrcode library that I'm using, unfortunately. If there's interest, perhaps I'll hack in support sometime.
Using the App
The app is fairly straightforward. When it first starts, the file browser will
automatically open to the qrcodes directory and display any .qrcode files.
Select one using the arrow keys and the center button. The qrcode will display.
If you push the right arrow, some stats will display: the qrcode "Version" -
which corresponds to how big it is; the ECC level - which determines the
qrcode's resilience to damage, such as a dirty screen (Low, Medium, Quartile,
and High); and the qrcode Mode (Numeric, Alpha-Numeric, Binary, or Kanji).
While viewing the stats, you can select Version or ECC using the up and down arrows and the center button. You can then increase or decrease the Version or ECC using up and down and save your choice using the center buttton. This feature was mostly added for my own amusement and testing, but, theoretically, it may help a reader that's having trouble if the default ECC is less than the highest value ("H"): you can increase the Version by 1 and then set the ECC to "H". Whether or not this helps depends on the reader.
You can hide the stats by pressing the left arrow.
When you're done viewing the qrcode, press the back button to return to the file browser. If you push the back button in the file browser, the app will exit.
I will ask that you temper your expectations: the Flipper Zero screen is small and many readers may have difficulty reading the qrcodes, especially if they are encoding a lot of data. However, I have successfully got my iPhone to read qrcodes encoding phone numbers, wifi info, and a url, all the way up to a version 11 qrcode (ie, the largest size the screen will fit).
Example: Wifi QRCodes
Most phones can automatically connect to wifi networks from a qrcode. If you should like to encode your wifi's connection info into a qrcode, here's how you'd do it:
Filetype: QRCode
Version: 0
Message: WIFI:S:<ssid>;P:<password>;T:<encryption>;
Replace <ssid> with the name of your wifi, <password> with the password.
<encryption> would be "WPA" or "WEP". If your wifi is open (no password),
this can be "None" and you can remove P:<password>; from the message. If your
wifi is hidden (ie, does not broadcast the ssid), you can add H:true; to the
end.
Note that if your ssid or password contain any of these characters: \";,:,
you'll need to "escape" it by placing a backslash (\) before it.
For example, if my ssid was "wifiball" and not broadcast, and the password was "pa$$:word" with WPA encryption, the message would be:
Message: WIFI:S:wifiball;P:pa$$\:word;T:WPA;H:true;
Building
First, clone the flipperzero-firmware repo and then clone this repo in the
applications_user directory:
git clone git@github.com:flipperdevices/flipperzero-firmware.git
cd flipperzero-firmware/applications_user
git clone git@github.com:bmatcuk/flipperzero-qrcode.git
Next, in the base of the flipperzero-firmware directory, run fbt:
cd ..
./fbt fap_qrcode
This will automatically install dependencies and build the application. When it
has finished building, the .fap will be in
build/f7-firmware-D/.extapps/qrcode.fap (fbt output will tell you where to
find the .fap, should it change in the future).
qrcode library
This application uses the QRCode library by ricmoo. This is the same library that is in the lib directory of the flipper-firmware repo (which was originally included for a now-removed demo app), but modified slightly to fix some compiler errors.