Lucent Technologies manual Preliminary Data Sheet, Rev, USS-720 Instant USB, September

Preliminary Data Sheet, Rev. 5				USS-720Instant USB
September 1999				USB-to-IEEE1284 Bridge
USB Port (continued)
Interface 0, Alternate Setting 1 (I0:A1)
Table 8. Interface Descriptor, I0:A1
Offset	Field	Size	Value	Description
0	bLength	Byte	0x09	Size of this descriptor in bytes.
1	bDescriptorType	Byte	0x04	Interface descriptor type.
2	bInterfaceNumber	Byte	0x00	Zero-based value identifying the number of this interface.
3	bAlternateSetting	Byte	0x01	Value used to select this alternate interface.
4	bNumEndpoints	Byte	0x02	Number of endpoints used by this descriptor.
5	bInterfaceClass	Byte	0x07	Printer class.
6	iInterfaceSubClass	Byte	0x01	Printer subclass.
7	bInterfaceProtocol	Byte	0x02	Bidirectional interface.
8	iInterface	Byte	0x00	Index to string describing this interface.
Table 9. Bulk Out Endpoint Descriptor, I0:A1:E1
Offset	Field	Size	Value	Description
0	bLength	Byte	0x07	Size of this descriptor in bytes.
1	bDescriptorType	Byte	0x05	Endpoint descriptor type.
2	bEndpointAddress	Byte	0x01	This is an Out endpoint, endpoint number 1.
3	bmAttributes	Byte	0x02	This is a Bulk endpoint.
4	wMaxPacketSize	Word	0x0040	Maximum data transfer size.
6	bInterval	Byte	0x00	Does not apply to Bulk endpoints.
Table 10. Bulk In Endpoint Descriptor, I0:A1:E2
Offset	Field	Size	Value	Description
0	bLength	Byte	0x07	Size of this descriptor in bytes.
1	bDescriptorType	Byte	0x05	Endpoint descriptor type.
2	bEndpointAddress	Byte	0x82	This is an In endpoint, endpoint number 2.
3	bmAttributes	Byte	0x02	This is a Bulk endpoint.
4	wMaxPacketSize	Word	0x0040	Maximum data transfer size.
6	bInterval	Byte	0x00	Does not apply to Bulk endpoints.

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