pw::spi::Responder Class Reference

Overview

Provides an abstract interface used to receive and transmit data on the responder side of a SPI bus. It is the common interface for implementing a SPI responder. It provides a way to respond to SPI transactions coming from a SPI initiator in a non-target specific way. A concrete implementation of the Responder class should be provided for the target hardware. Applications can then use it to implement their specific protocols.

Public Member Functions
void	SetCompletionHandler (Function< void(ByteSpan, Status)> callback)
Status	WriteReadAsync (ConstByteSpan tx_data, ByteSpan rx_data)
void	Cancel ()

Member Function Documentation

Cancel()

void pw::spi::Responder::Cancel ( )

inline

Cancel the outstanding WriteReadAsync call. The completion handler will be called with a Status of CANCELLED after this is called.

SetCompletionHandler()

void pw::spi::Responder::SetCompletionHandler ( Function< void(ByteSpan, Status)>  callback )

inline

Sets callback to be called when SPI transaction completes. callback can be called in an interrupt context. callback should not be changed during execution of a completion.

A value of CANCELLED for the Status parameter indicates Cancel() was called. Partially transferred data may be passed in that case as well. Other Status values are implementer-defined.

WriteReadAsync()

Status pw::spi::Responder::WriteReadAsync ( ConstByteSpan  tx_data, ByteSpan  rx_data  )

inline

tx_data is queued for TX when called, but only transmitted when the initiator starts the next transaction. It's up to the implementer to define how stuffing bytes are handled. rx_data is populated as the initiator transfers data. A slice of rx_data is passed as a span to the completion callback.

Only one outstanding request should be active. UNAVAILABLE will be returned if a transaction is already established.

The completion handler will always be invoked, even in the case of an Cancel(). In that case a Status value of CANCELLED will be passed.

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The documentation for this class was generated from the following file:

• pw_spi/public/pw_spi/responder.h