retryCounter property

int? get retryCounter

The attempts still left before the card locks, when it answered 63Cx to a failed verification. Null for every other warning.

Zero is a real answer and means the next failure is not survivable -- which is exactly the moment to stop retrying a PIN rather than burning the last attempt.

Implementation

int? get retryCounter => statusWord1 == 0x63 && (statusWord2 & 0xF0) == 0xC0 ? statusWord2 & 0x0F : null;