# Notification Structures

This page aggregates all notification-related structures shared by the C and C++ APIs.

Note

`Notification::i3cHotJoin()`, `Notification::i3cIbi()`, `Notification::gpio()` and `Notification::uartRx()` are C++ convenience methods only (available under `#ifdef __cplusplus`). They are not part of the C API. In C, use `CosmicSDK_notificationAsI3cHotJoin`, `CosmicSDK_notificationAsI3cIbi`, `CosmicSDK_notificationAsGpio` and `CosmicSDK_notificationAsUartRx` from `CosmicSDK_API_c.h`.

group Notification-related structures
  struct I3cHotJoinNotification
    #include <CosmicNotifications.h>

    Parsed I3C Hot-Join notification information.

    Public Members

    uint8_t pid[6]

      Provisional ID (48-bit) reported by the device during Hot-Join.

    uint8_t bcr

      Bus Characteristics Register value of the joining device.

    uint8_t dcr

      Device Characteristics Register value of the joining device.

    uint8_t dynamicAddress

      Dynamic address assigned by the controller after Hot-Join.

  struct I3cIbiNotification
    #include <CosmicNotifications.h>

    Parsed I3C In-Band Interrupt (IBI) notification information.

    Public Members

    uint8_t address

      Dynamic address of the device that generated the IBI.

    const uint8_t *payload

      Pointer to the optional IBI payload data (if present).

    size_t payloadLength

      Length in bytes of the IBI payload.

  struct UartRxNotification
    #include <CosmicNotifications.h>

    Parsed UART RX notification. This struct holds the data received through the UART.

    Public Members

    const uint8_t *data

      Pointer to the received UART data buffer.

    size_t dataLength

      Number of bytes received in the buffer.

  struct GpioInterruptNotification
    #include <CosmicNotifications.h>

    Parsed GPIO Interrupt notification information.

    Public Members

    uint8_t pinNumber

      GPIO pin number that triggered the interrupt.

  struct Notification
    #include <CosmicNotifications.h>

    Generic notification wrapper used by both C and C++ APIs.

    This structure is delivered by callback-based APIs:

    - C API: CosmicSDK_onNotification

    - C++ API: CosmicSDK::onNotification

    The `type` field identifies the notification category. The payload bytes are exposed through `payload` and `payloadLength`.

    Parsing:

    - C users should call the dedicated parser helpers: CosmicSDK_notificationAsI3cHotJoin, CosmicSDK_notificationAsI3cIbi, CosmicSDK_notificationAsGpio, CosmicSDK_notificationAsUartRx.

    - C++ users can call the convenience methods: i3cHotJoin, i3cIbi, gpio, uartRx.

    Public Functions

    inline Notification(NotificationType t, const uint8_t *p, size_t len) noexcept

      Constructs a Notification with the given type and payload.

      Note

      C++ only. Not available in the C API.

      Parameters:

        - t – The notification type.

        - p – Pointer to the notification payload data.

        - len – Length of the payload data in bytes.

    const I3cHotJoinNotification *i3cHotJoin() const noexcept

      Parses this notification as I3C Hot-Join data.

      This method validates `type` and payload length before decoding.

      Note

      C++ only. Not available in the C API.

      Returns:

        Pointer to parsed I3cHotJoinNotification when this is a valid `NOTIF_I3C_HJ` notification; otherwise `nullptr`.

    const I3cIbiNotification *i3cIbi() const noexcept

      Parses this notification as I3C In-Band Interrupt (IBI) data.

      This method validates `type` and payload length before decoding.

      Note

      C++ only. Not available in the C API.

      Returns:

        Pointer to parsed I3cIbiNotification when this is a valid `NOTIF_I3C_IBI` notification; otherwise `nullptr`.

    const GpioInterruptNotification *gpio() const noexcept

      Parses this notification as GPIO interrupt data.

      This method validates `type` and payload length before decoding.

      Note

      C++ only. Not available in the C API.

      Returns:

        Pointer to parsed GpioInterruptNotification when this is a valid `NOTIF_GPIO` notification; otherwise `nullptr`.

    const UartRxNotification *uartRx() const noexcept

      Parses this notification as UART RX data.

      This method validates `type` and payload length before decoding.

      Note

      C++ only. Not available in the C API.

      Returns:

        Pointer to parsed UartRxNotification when this is a valid `NOTIF_UART` notification; otherwise `nullptr`.

    Public Members

    NotificationType type

      Notification type. See NotificationType for valid values.

    const uint8_t *payload

      Pointer to raw notification payload bytes.

      The payload format depends on `type`.

    size_t payloadLength

      Payload size in bytes.