EVT_SERCX2_PIO_RECEIVE_INITIALIZE_TRANSACTION callback function (sercx.h)

Article
02/22/2024

The EvtSerCx2PioReceiveInitializeTransaction event callback function is called by version 2 of the serial framework extension (SerCx2) to prepare the serial controller to perform a PIO-receive transaction.

Syntax

EVT_SERCX2_PIO_RECEIVE_INITIALIZE_TRANSACTION EvtSercx2PioReceiveInitializeTransaction;

void EvtSercx2PioReceiveInitializeTransaction(
  [in] SERCX2PIORECEIVE PioReceive,
  [in] ULONG Length
)
{...}

Parameters

[in] PioReceive

A SERCX2PIORECEIVE handle to a PIO-receive object. The serial controller driver previously called the SerCx2PioReceiveCreate method to create this object.

[in] Length

The number of bytes to be transferred in the PIO-receive transaction.

Return value

None

Remarks

Your serial controller driver can, as an option, implement this function. If implemented, the driver registers the function in the call to the SerCx2PioReceiveCreate method that creates the PIO-receive object.

Your driver should implement an EvtSerCx2PioReceiveInitializeTransaction function if it needs to initialize the serial controller and associated hardware in preparation for a new PIO-receive transaction. SerCx2 calls this function, if it is implemented, before a PIO-receive transaction starts. In response to this call, the serial controller driver must call the SerCx2PioReceiveInitializeTransactionComplete method to notify SerCx2 after the initialization is finished.

For more information, see SerCx2 PIO-Receive Transactions.

Examples

To define an EvtSerCx2PioReceiveInitializeTransaction callback function, you must first provide a function declaration that identifies the type of callback function you're defining. Windows provides a set of callback function types for drivers. Declaring a function using the callback function types helps Code Analysis for Drivers, Static Driver Verifier (SDV), and other verification tools find errors, and it's a requirement for writing drivers for the Windows operating system.

For example, to define an EvtSerCx2PioReceiveInitializeTransaction callback function that is named MyPioReceiveInitializeTransaction, use the EVT_SERCX2_PIO_RECEIVE_INITIALIZE_TRANSACTION function type, as shown in this code example:

EVT_SERCX2_PIO_RECEIVE_INITIALIZE_TRANSACTION  MyPioReceiveInitializeTransaction;

Then, implement your callback function as follows:

_Use_decl_annotations_
VOID
  MyPioReceiveInitializeTransaction(
    SERCX2PIORECEIVE  PioReceive,
    ULONG  Length
    )
  {...}

The EVT_SERCX2_PIO_RECEIVE_INITIALIZE_TRANSACTION function type is defined in the Sercx.h header file. To more accurately identify errors when you run the code analysis tools, be sure to add the Use_decl_annotations annotation to your function definition. The Use_decl_annotations annotation ensures that the annotations that are applied to the EVT_SERCX2_PIO_RECEIVE_INITIALIZE_TRANSACTION function type in the header file are used. For more information about the requirements for function declarations, see Declaring Functions by Using Function Role Types for KMDF Drivers. For more information about Use_decl_annotations, see Annotating Function Behavior.

Requirements

Requirement	Value
Minimum supported client	Available starting with Windows 8.1.
Target Platform	Desktop
Header	sercx.h
IRQL	Called at IRQL <= DISPATCH_LEVEL.