Module for advanced isochronous transfers. (libusbK only) More...

Data Structures
struct	KISO_PACKET
	Structure describing an isochronous transfer packet for libusbK. More...

struct	KISO_WUSB_PACKET
	Structure describing an isochronous transfer packet for winusb. More...

struct	KISO_CONTEXT
	Structure describing a user defined isochronous transfer. More...

struct	KISOCH_PACKET_INFORMATION
	Structure describing additional information about how an isochronous pipe transfers data. More...

Typedefs
typedef BOOL KUSB_API	KISO_ENUM_PACKETS_CB (_in UINT PacketIndex, _in PKISO_PACKET IsoPacket, _in PVOID UserState)
	Callback function typedef for IsoK_EnumPackets.

typedef BOOL KUSB_API	KISOCH_ENUM_PACKETS_CB (_in UINT PacketIndex, _ref PUINT Offset, _ref PUINT Length, _ref PUINT Status, _in PVOID UserState)
	Callback function typedef for IsochK_EnumPackets.

typedef KISO_PACKET *	PKISO_PACKET
	pointer to a `KISO_PACKET` structure

typedef KISO_WUSB_PACKET *	PKISO_WUSB_PACKET
	pointer to a `KISO_PACKET` structure

typedef KISO_CONTEXT *	PKISO_CONTEXT
	pointer to a `KISO_CONTEXT` structure

typedef KISOCH_PACKET_INFORMATION *	PKISOCH_PACKET_INFORMATION
	pointer to a `KISOCH_PACKET_INFORMATION` structure

Enumerations
enum	KISO_FLAG { , KISO_FLAG_SET_START_FRAME = 0x00000001 }
	Additional ISO transfer flags. More...

Functions
KUSB_EXP BOOL KUSB_API	IsoK_Init (_out PKISO_CONTEXT *IsoContext, _in INT NumberOfPackets, _inopt INT StartFrame)
	Creates a new isochronous transfer context for libusbK only. More...

KUSB_EXP BOOL KUSB_API	IsoK_Free (_in PKISO_CONTEXT IsoContext)
	Destroys an isochronous transfer context. More...

KUSB_EXP BOOL KUSB_API	IsoK_SetPackets (_in PKISO_CONTEXT IsoContext, _in INT PacketSize)
	Convenience function for setting the offset of all ISO packets of an isochronous transfer context. More...

KUSB_EXP BOOL KUSB_API	IsoK_SetPacket (_in PKISO_CONTEXT IsoContext, _in INT PacketIndex, _in PKISO_PACKET IsoPacket)
	Convenience function for setting all fields of a KISO_PACKET. More...

KUSB_EXP BOOL KUSB_API	IsoK_GetPacket (_in PKISO_CONTEXT IsoContext, _in INT PacketIndex, _out PKISO_PACKET IsoPacket)
	Convenience function for getting all fields of a KISO_PACKET. More...

KUSB_EXP BOOL KUSB_API	IsoK_EnumPackets (_in PKISO_CONTEXT IsoContext, _in KISO_ENUM_PACKETS_CB *EnumPackets, _inopt INT StartPacketIndex, _inopt PVOID UserState)
	Convenience function for enumerating ISO packets of an isochronous transfer context. More...

KUSB_EXP BOOL KUSB_API	IsoK_ReUse (_ref PKISO_CONTEXT IsoContext)
	Convenience function for re-using an isochronous transfer context in a subsequent request. More...

Detailed Description

Module for advanced isochronous transfers. (libusbK only)

Enumeration Type Documentation

enum KISO_FLAG

Additional ISO transfer flags.

Enumerator

KISO_FLAG_SET_START_FRAME

Do not start the transfer immediately, instead use KISO_CONTEXT::StartFrame.

By default, isochronous transfers start on the next frame and KISO_CONTEXT::StartFrame is ignored. If this flag is specified, the transfer is postponed until the current usb frame number equals that specified by KISO_CONTEXT::StartFrame.

Under certain circumstances, the driver can specify 0 for KISO_CONTEXT::StartFrame, and the bus driver will begin the transaction in the next available frame.

Specifing 0 for KISO_CONTEXT::StartFrame (start transfer ASAP) is restricted to the first transaction on a newly opened or reset pipe. Furthermore, the USB stack contains a bug in Microsoft Windows Server 2003 and Windows XP that limits the use of this to an isochronous context with 255 or fewer packets.

For more information about resetting pipes, see UsbK_ResetPipe.

Function Documentation

KUSB_EXP BOOL KUSB_API IsoK_Init	(	_out PKISO_CONTEXT *	IsoContext,
		_in INT	NumberOfPackets,
		_inopt INT	StartFrame
	)

Creates a new isochronous transfer context for libusbK only.

Parameters

[out]	IsoContext	Receives a new isochronous transfer context.
[in]	NumberOfPackets	The number of KISO_PACKET structures allocated to `IsoContext`. Assigned to KISO_CONTEXT::NumberOfPackets. The KISO_CONTEXT::NumberOfPackets field is assignable by `IsoK_Init` only and must not be changed by the user.
[in]	StartFrame	The USB frame number this request must start on (or 0 for ASAP) and assigned to KISO_CONTEXT::StartFrame. The KISO_CONTEXT::StartFrame may be chamged by the user in subsequent request. For more information, see KISO_CONTEXT::StartFrame.

Returns: On success, TRUE. Otherwise FALSE. Use GetLastError() to get extended error information.

IsoK_Init is performs the following tasks in order:

Allocates the IsoContext and the required KISO_PACKET structures.
Zero-initializes all ISO context memory.
Assigns NumberOfPackets, PipeID, and StartFrame to IsoContext.

KUSB_EXP BOOL KUSB_API IsoK_Free ( _in PKISO_CONTEXT IsoContext )

Destroys an isochronous transfer context.

Parameters

[in] IsoContext A pointer to an isochronous transfer context created with IsoK_Init.

Returns: On success, TRUE. Otherwise FALSE. Use GetLastError() to get extended error information.

KUSB_EXP BOOL KUSB_API IsoK_SetPackets	(	_in PKISO_CONTEXT	IsoContext,
		_in INT	PacketSize
	)

Convenience function for setting the offset of all ISO packets of an isochronous transfer context.

Parameters

[in]	IsoContext	A pointer to an isochronous transfer context.
[in]	PacketSize	The packet size used to calculate and assign the absolute data offset for each KISO_PACKET in `IsoContext`.

Returns: On success, TRUE. Otherwise FALSE. Use GetLastError() to get extended error information.

IsoK_SetPackets updates all KISO_PACKET::Offset fields in a KISO_CONTEXT so all offset are PacketSize apart. For example:

The offset of the first (0-index) packet is 0.
The offset of the second (1-index) packet is PacketSize.
The offset of the third (2-index) packet is PacketSize*2.

for (packetIndex = 0; packetIndex < IsoContext->NumberOfPackets; packetIndex++)

IsoContext->IsoPackets[packetIndex].Offset = packetIndex * PacketSize;

KUSB_EXP BOOL KUSB_API IsoK_SetPacket	(	_in PKISO_CONTEXT	IsoContext,
		_in INT	PacketIndex,
		_in PKISO_PACKET	IsoPacket
	)

Convenience function for setting all fields of a KISO_PACKET.

Parameters

[in]	IsoContext	A pointer to an isochronous transfer context.
[in]	PacketIndex	The packet index to set.
[in]	IsoPacket	Pointer to a user allocated `KISO_PACKET` which is copied into the PKISO_CONTEXT::IsoPackets array at the specified index.

Returns: On success, TRUE. Otherwise FALSE. Use GetLastError() to get extended error information.

KUSB_EXP BOOL KUSB_API IsoK_GetPacket	(	_in PKISO_CONTEXT	IsoContext,
		_in INT	PacketIndex,
		_out PKISO_PACKET	IsoPacket
	)

Convenience function for getting all fields of a KISO_PACKET.

Parameters

[in]	IsoContext	A pointer to an isochronous transfer context.
[in]	PacketIndex	The packet index to get.
[out]	IsoPacket	Pointer to a user allocated `KISO_PACKET` which receives a copy of the ISO packet in the PKISO_CONTEXT::IsoPackets array at the specified index.

Returns: On success, TRUE. Otherwise FALSE. Use GetLastError() to get extended error information.

KUSB_EXP BOOL KUSB_API IsoK_EnumPackets	(	_in PKISO_CONTEXT	IsoContext,
		_in KISO_ENUM_PACKETS_CB *	EnumPackets,
		_inopt INT	StartPacketIndex,
		_inopt PVOID	UserState
	)

Convenience function for enumerating ISO packets of an isochronous transfer context.

Parameters

[in]	IsoContext	A pointer to an isochronous transfer context.
[in]	EnumPackets	Pointer to a user supplied callback function which is executed for all ISO packets in `IsoContext` or until the user supplied callback function returns `FALSE`.
[in]	StartPacketIndex	The zero-based ISO packet index to begin enumeration at.
[in]	UserState	A user defined value which is passed as a parameter to the user supplied callback function.

Returns: On success, TRUE. Otherwise FALSE. Use GetLastError() to get extended error information.

KUSB_EXP BOOL KUSB_API IsoK_ReUse ( _ref PKISO_CONTEXT IsoContext )

Convenience function for re-using an isochronous transfer context in a subsequent request.

Parameters

[in,out] IsoContext A pointer to an isochronous transfer context.

Returns: On success, TRUE. Otherwise FALSE. Use GetLastError() to get extended error information.

IsoK_ReUse does the following:

Zero-initializes the Length and Status fields of all KISO_PACKET structures.
Zero-initializes the StartFrame and ErrorCount of the KISO_CONTEXT.

Data Structures

Typedefs

Enumerations

Functions

Detailed Description

Enumeration Type Documentation

Function Documentation