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# CardSession.APDU

An Application Programming Data Unit (APDU) received from the NFC card reader.

```
final class APDU
```

## Topics

### Receiving data

[`let payload: Data`](/documentation/CoreNFC/CardSession/APDU/payload)

The APDU data received from the NFC reader.

### Communicating with the card session

[`func respond(response: Data) async throws`](/documentation/CoreNFC/CardSession/APDU/respond(response:))

Respond to the session after receiving and processing an APDU.

## Relationships

### Conforms To

[`Escapable`](/documentation/Swift/Escapable)

[`Sendable`](/documentation/Swift/Sendable)

[`CustomDebugStringConvertible`](/documentation/Swift/CustomDebugStringConvertible)

[`Copyable`](/documentation/Swift/Copyable)

[`Equatable`](/documentation/Swift/Equatable)

[`SendableMetatype`](/documentation/Swift/SendableMetatype)

---

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