Emv About Fallback - chuwuwang/ReadingNote GitHub Wiki
When the IC card data is corrupted and the contact transaction cannot be execute, the card is allowed to be downgraded and the transaction is made using the magnetic stripe card, a process called Fallback.
When to Fallback is performed when:
- when reset fails.
- when cannot find an application that matches the terminal
- when the initialization application returns something other than 9000 and 6985
- the first GAC returned at 6985
Processing flow: When the contact transaction is unsuccessful, the terminal will prompt the card swipe operation. When the contact transaction is invalid, only magnetic card transaction can be carried out.
Message processing: If the IC card is swiped, the related message goes to Fallback message. If not swiped IC card, or the normal magnetic stripe card message.
Note
IN China, at present, the People's Bank of China has made a notice to close the processing of financial IC composite card downgrade transactions, requiring the issuing end of the card to close the downgrade transaction should be a uniform return to the receiving end of the "45" code.
The "45" code returned by the processing terminal to the issuing terminal to close a downgrade transaction should read "Please use the chip, if it is damaged please contact the issuing bank".