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nRF24AP2-USB Product Specification

The interface descriptor contains information about the number of endpoints and their class.

Table 7. Interface descriptor

Endpoint descriptors contain information about the transfer type, interval and the packet size. The host will

use the information to decide on the requirements for the bus. The nRF24AP2-USB uses two endpoints for

communication with the host, one configured as IN and the other as OUT.

Table 8. Endpoint descriptor 1 IN

Table 9. Endpoint descriptor 1 OUT

Field

Notes

Value

Description

bLength

0x09

Valid

bDescriptorType

0x04

INTERFACE

bInterfaceNumber

0x00

0

bAlternateSetting

0x00

0

bNumEndpoints

0x02

2

bInterfaceClass

0xFF

Vendor-specific

bInterfaceSubClass

0x00

Vendor-specific

bInterfaceProtocol

0x00

None

iInterface

0x02

2

Field

Notes

Value

Description

bLength

0x07

Valid

bDescriptorType

0x05

ENDPOINT

bEndpointAddress

0x81

1 IN

bmAttributes.

TransferType

0x2

Bulk

bmAttributes. Reserved

0x00

Zero

wMaxPacketSize

0x0040

64 bytes

bInterval

0x01

Ignored for full speed,

Bulk endpoints

Field

Notes

Value

Description

bLength

0x07

Valid

bDescriptorType

0x05

ENDPOINT

bEndpointAddress

0x01

1 OUT

bmAttributes.

TransferType

0x2

Bulk

bmAttributes. Reserved

0x00

Zero

wMaxPacketSize

0x0040

64 bytes

bInterval

0x01

Ignored for full speed,

Bulk endpoints