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Chapter 8

 

Wire Adapter

Wireless Universal Serial Bus Specification, Revision 1.0

8.4.3.16Isochronous Streaming OUT Endpoint Companion Descriptor

Table 8-30. Isochronous Streaming OUT Endpoint Companion Descriptor

Offset

Field

Size

Value

Description

 

 

 

 

 

0

bLength

1

0AH

Size of this descriptor in bytes

 

 

 

 

 

1

bDescriptorType

1

17

WIRELESS_ENDPOINT_COMPANION Descriptor

 

 

 

 

Type

 

 

 

 

 

2

bMaxBurst

1

Number

The value of this field must adhere to the rules

 

 

 

 

specified in Section 4.7.1

 

 

 

 

 

3

bMaxSequence

1

Number

The maximum sequence used for data bursting.

 

 

 

 

Valid values are in the range 2 to 32.

 

 

 

 

 

4

wMaxStreamDelay

2

Number

Maximum supported stream delay.

 

 

 

 

The actual stream delay is determined by the DWA

 

 

 

 

driver.

6

wOverTheAirPacketSize

2

Number

Maximum packet size this endpoint is capable of

 

 

 

 

receiving over the air.

8

bOverTheAirInterval

1

00H

Interval for polling endpoint for data transfers. Since

 

 

 

 

this is a dynamic switching capable endpoint, this

 

 

 

 

endpoint supports all valid values from 4 through

 

 

 

 

255.

 

 

 

 

 

9

bmCompAttributes

1

02H

This endpoint supports continuously scalable

 

 

 

 

dynamic switching.

 

 

 

 

 

8.4.3.17Isochronous Streaming IN Endpoint Descriptor

Table 8-31. Isochronous Streaming IN Endpoint Descriptor

Offset

Field

Size

Value

Description

 

 

 

 

 

0

bLength

1

7

Size of this descriptor in bytes, including this field.

 

 

 

 

 

1

bDescriptorType

1

5

ENDPOINT Descriptor Type

 

 

 

 

 

2

bEndpointAddress

1

Number

The address of this endpoint

 

 

 

 

 

3

bmAttributes

1

01H

Isochronous endpoint.

 

 

 

 

 

4

wMaxPacketSize

2

Number

The logical MaxPacketSize must be set to the same

 

 

 

 

value as the over the air MaxPacketSize.

6

bInterval

1

0

The logical service Interval must be set to the same

 

 

 

 

value as the over-the-air service interval.

226

Chapter 8

 

Wire Adapter

Wireless Universal Serial Bus Specification, Revision 1.0

8.4.3.18Isochronous Streaming IN Endpoint Companion Descriptor

Table 8-32. Isochronous Streaming IN Endpoint Companion Descriptor

Offset

Field

Size

Value

Description

 

 

 

 

 

0

bLength

1

0AH

Size of this descriptor in bytes

 

 

 

 

 

1

bDescriptorType

1

17

WIRELESS_ENDPOINT_COMPANION Descriptor

 

 

 

 

Type

 

 

 

 

 

2

bMaxBurst

1

Number

The value of this field must adhere to the rules

 

 

 

 

specified in Section 4.7.1

 

 

 

 

 

3

bMaxSequence

1

Number

The maximum sequence used for data bursting.

 

 

 

 

Valid values are in the range 2 to 32.

 

 

 

 

 

4

wMaxStreamDelay

2

Number

Maximum supported stream delay. The actual

 

 

 

 

stream delay is determined by the DWA driver.

 

 

 

 

 

6

wOverTheAirPacketSize

2

Number

Maximum packet size this endpoint is capable of

 

 

 

 

sending over the air.

 

 

 

 

 

8

bOverTheAirInterval

1

00H

Interval for polling endpoint for data transfers. Since

 

 

 

 

this is a dynamic switching capable endpoint, this

 

 

 

 

endpoint supports all valid values from 4 through

 

 

 

 

255.

9

bmCompAttributes

1

02H

This endpoint supports continuously scalable

 

 

 

 

dynamic switching.

8.4.3.19Wire Adapter RPipe Descriptor

The Wire Adapter RPipe descriptors are not returned as part of the configuration descriptor for a DWA. Host software can get each RPipe descriptor by sending a Get RPipe Descriptor (See Section 8.3.1.4) request to the DWA. The format of the Wire Adapter RPipe descriptor and the description of the fields is given in Table 8-33.

Table 8-33. Wire Adapter RPipe Descriptor

Offset

Field

Size

Value

Description

 

 

 

 

 

0

bLength

1

1CH

Size of this descriptor in bytes, including this field.

 

 

 

 

This is a read only field.

1

bDescriptorType

1

22H

Wire Adapter RPipe Descriptor Type. This is a read

 

 

 

 

only field.

 

 

 

 

 

2

wRPipeIndex

2

Number

Number of this RPipe. Zero-based value identifying

 

 

 

 

the index in the array of concurrent RPipes

 

 

 

 

supported by this Wire Adapter. This is a read only

 

 

 

 

field.

 

 

 

 

 

4

wRequests

2

Number

The number of concurrent requests that can be

 

 

 

 

assigned to this RPipe. This is a read only field.

6

wBlocks

2

Number

The number of buffer blocks assigned to this RPipe.

 

 

 

 

If the value in this field is zero then the Set RPipe

 

 

 

 

Descriptor request can be used to set the number of

 

 

 

 

blocks to be assigned to this RPipe.

 

 

 

 

If the value in this field is not zero then the number

 

 

 

 

of blocks assigned to this RPipe cannot be changed

 

 

 

 

by host software.

 

 

 

 

This field may be modified by host software if this is

 

 

 

 

set to zero.

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Chapter 8

 

Wire Adapter

Wireless Universal Serial Bus Specification, Revision 1.0

Table 8-33. Wire Adapter RPipe Descriptor (cont.)

Offset

Field

Size

Value

 

Description

 

 

 

 

 

8

wMaxPacketSize

2

Number

Maximum packet size that this RPipe will use to

 

 

 

 

communicate with attached device.

 

 

 

 

 

10

bHSHubAddress

1

Number

This is the address of the attached device’s parent

 

 

 

 

high speed hub. This number is used only when a

 

 

 

 

full/low device is connected to the DWA through a

 

 

 

 

high speed hub. This field must be set to Zero if the

 

 

 

 

full/low speed device is directly connected to the

 

 

 

 

DWA.

 

 

 

 

 

This field is reserved if the bSpeed field is set to

 

 

 

 

High Speed.

 

 

 

 

 

 

11

bHSHubPort

1

Number

This is the Port number on which the attached

 

 

 

 

device is connected to its parent high speed hub.

 

 

 

 

This number is used only when a full/low device is

 

 

 

 

connected to the DWA through a high speed hub.

 

 

 

 

This field must be set to Zero if the full/low speed

 

 

 

 

device is directly connected to the DWA.

 

 

 

 

This field is reserved if the bSpeed field is set to

 

 

 

 

High Speed.

 

 

 

 

 

 

12

bSpeed

1

Number

The speed of device to be targeted by RPipe.

 

 

 

 

Value

Description

 

 

 

 

00B

Full-Speed (12Mbs)

 

 

 

 

01B

Low-Speed (1.5Mbs)

 

 

 

 

10B

High-Speed (480 Mbs)

 

 

 

 

11B

Reserved

 

 

 

 

 

13

bDeviceAddress

1

Number

Address to be used with attached device

 

 

 

 

 

14

bEndpointAddress

1

Number

Endpoint Address to be used with this RPipe.

 

 

 

 

Bit

Description

 

 

 

 

3:0

The endpoint number

 

 

 

 

6:4

Reserved; set to zero

 

 

 

 

7

Direction, ignored for control

 

 

 

 

 

endpoints

 

 

 

 

 

0 = OUT endpoint

 

 

 

 

 

1 = IN endpoint

 

 

 

 

 

15

bDataSequence

1

Number

Current data sequence. This is the next data

 

 

 

 

sequence value to be used when sending data to

 

 

 

 

the endpoint that this RPipe is targeted at.

 

 

 

 

 

16

dwCurrentWindow

4

Number

Reserved and must be set to zero.

 

 

 

 

 

20

bMaxDataSequence

1

Number

Reserved and must be set to zero.

 

 

 

 

 

21

bInterval

1

Number

Polling interval to be used by this RPipe in

 

 

 

 

downstream communications

 

 

 

 

 

22

bOverTheAirInterval

1

Number

If the transfer type is Isochronous, then this is the

 

 

 

 

interval at which the upstream wireless endpoint is

 

 

 

 

polled. See bOverTheAirInterval in Table 7-32 for

 

 

 

 

the encoding of this field.

 

 

 

 

This field is Reserved and must be set to zero for all

 

 

 

 

other transfer types.

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Chapter 8

 

Wire Adapter

Wireless Universal Serial Bus Specification, Revision 1.0

Table 8-33. Wire Adapter RPipe Descriptor (cont.)

Offset

Field

Size

Value

 

Description

 

 

 

 

 

 

23

bmAttribute

1

Bitmap

Bit

Description

 

 

 

 

1:0

Value

Transfer Type

 

 

 

 

 

00B

Control

 

 

 

 

 

01B

Isochronous

 

 

 

 

 

10B

Bulk

 

 

 

 

 

11B

Interrupt

 

 

 

 

5:2

If the transfer type is Isochronous,

 

 

 

 

 

then this field indicates the

 

 

 

 

 

associated upstream Isochronous

 

 

 

 

 

endpoint on the DWA.

 

 

 

 

 

This field is Reserved and must be

 

 

 

 

 

set to zero for all other transfer

 

 

 

 

 

types.

 

 

 

 

 

7:6

Reserved

 

 

 

 

 

 

24

bmCharacteristics

1

Bitmap

Transfer types supported on this RPipe

 

 

 

 

Bit

Description

 

 

 

 

0

1: Control Transfer supported

 

 

 

 

 

0: Control Transfer NOT supported

 

 

 

 

1

1: Isochronous Transfer supported

 

 

 

 

 

0: Isochronous Transfer NOT

 

 

 

 

 

supported

 

 

 

 

2

1: Bulk Transfer supported

 

 

 

 

 

0: Bulk Transfer NOT supported

 

 

 

 

3

1: Interrupt Transfer supported

 

 

 

 

 

0: Interrupt Transfer NOT

 

 

 

 

 

supported

 

 

 

 

7:4

Reserved

 

 

 

 

 

This is a read only field.

 

 

 

 

 

 

 

25

bmRetryOptions

1

Bitmap

Bit

Description

 

 

 

 

2:0

The maximum number of times a

 

 

 

 

 

transaction must be retried before

 

 

 

 

 

the transfer request is failed.

 

 

 

 

 

The valid values are 0 through 3. A

 

 

 

 

 

value of zero in this field indicates

 

 

 

 

 

that the DWA must not count errors

 

 

 

 

 

and there is no limit on the retries.

 

 

 

 

 

For Isochronous transfers this field is

 

 

 

 

 

set to zero.

 

 

 

 

 

7:3

Reserved.

 

 

 

 

 

 

26

wNumTransactionErrors

2

Number

The DWA increments this field when it encounters

 

 

 

 

an error while performing transactions to the

 

 

 

 

downstream endpoint targeted by this RPipe.

 

 

 

 

The host is responsible for resetting this field.

 

 

 

 

 

 

 

229

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