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IRB_REQ_ISOCH_MODIFY_STREAM_PROPERTIES structure (1394.h)

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This structure contains the fields necessary for the Bus driver to carry out an IsochModifyStreamProperties request. This request is used to dynamically change the properties of an allocated resource, without the need to free and re-allocate the resource. The resource must not be streaming when this is issued. The caller should issue an ISOCH_STOP first and then an ISOCH_START. Also, no buffer can be pending after the ISOCH_STOP and before this call is made.

Syntax

typedef struct _IRB_REQ_ISOCH_MODIFY_STREAM_PROPERTIES {
  HANDLE         hResource;
  ULARGE_INTEGER ChannelMask;
  ULONG          fulSpeed;
} IRB_REQ_ISOCH_MODIFY_STREAM_PROPERTIES;

Members

hResource

The handle for the allocated resource.

ChannelMask

Specifies the allocated channel.

fulSpeed

Specifies the connection speed to use for communication on the channel. The possible speed values are SPEED_FLAGS_xxx, where xxx is the (approximate) transfer rate in megabits per second. Existing hardware supports transfer rates of 100, 200, and 400 Mb/sec.

Transfer Rate Description
SPEED_FLAGS_100 100 Mb/s
SPEED_FLAGS_200 200 Mb/s
SPEED_FLAGS_400 400 Mb/s
 
Note  In Windows 7 and later versions of Windows, you can specify new values higher speed and greater sized payloads. For more information, see New Flags for Speed and Payload Size and IEEE 1394 IOCTL Changes in Device Driver Interface (DDI) Changes in Windows 7.
 

Remarks

The resource must not be streaming when REQUEST_ISOCH_MODIFY_STREAM_PROPERTIES is issued. Before issuing REQUEST_ISOCH_MODIFY_STREAM_PROPERTIES, the caller must send a REQUEST_ISOCH_STOP request followed by a start request. Also make sure that there are no pending buffers after the caller sends a REQUEST_ISOCH_STOP request and before the caller sends a REQUEST_ISOCH_MODIFY_STREAM_PROPERTIES request.

Requirements

Requirement Value
Header 1394.h