I know that ISO 7816 compliant cards, like modern EMV Chip and PIN cards, are typically used in a command response scenario, the reader sends a command APDU to the card, and the latter sends a response. However, can the card perform concurrent activities, such as perform any dummy action while it waits for a command from the reader, or does it have to wait passively?
The card does the action only based on the APDU command request. For a request, a response is expected, and in most cases in a sequence too. To say, you cannot do a GET PO before SELECT, you cannot request a GEN AC before GET PO.
But I am curious what the 'concurrent activities' possible, could you think aloud?