Most bitcoin wallets can read QR codes with additional parameters in BNF grammar above for the normative syntax. You can add amount, name, description and other parameters to your wallet. Some parameters may be changed, some cannot be understood or can be ignored by the wallet. Only the address and the amount will be stored in the bitcoin blockchain. Other parameters can or may be stored in your bitcoin wallet, it depends on the software.
Just the address:
Address with amount (recomended to use):
Request 20.30 BTC to "Luke-Jr":
Request 50 BTC with message:
Some future version that has variables which are (currently) not understood and required and thus invalid:
Some future version that has variables which are (currently) not understood but not required and thus valid:
|Parameter||Experiment with a value|