Philips Universal Serial Bus ISP1122 - Manual (Page 15)

Philips Semiconductors
ISP1122
USB stand-alone hub
Product specification Rev. 03 — 29 March 2000 15 of 48
9397 750 07002 © Philips Electronics N.V. 2000. All rights reserved.
9.3 Descriptors
The ISP1122 hub controller supports the following standard USB descriptors:
• Device
• Configuration
• Interface
• Endpoint
• Hub
• String.
Table 10: Device descriptor
Values in square brackets are optional.
Offset
(bytes) Field name Size
(bytes) Value
(Hex) Comments
0 bLength 1 12 descriptor length = 18 bytes
1 bDescriptorType 1 01 type = DEVICE
2 bcdUSB 2 10, 01 USB Specification Rev. 1.1
4 bDeviceClass 1 09 HUB_CLASSCODE
5 bDeviceSubClass 1 00 -
6 bDeviceProtocol 1 00 -
7 bMaxPacketSize0 1 40 packet size = 64 bytes
8 idVendor 2 CC, 04 Philips Semiconductors vendor ID
(04CC); can be customized using an
external EEPROM (see
Table 23 )
10 idProduct 2 22, 11 ISP1122 product ID; can be
customized using an external
EEPROM (see
Table 23 )
12 bcdDevice 2 01, 01 device release 1.1; silicon revision
increments this value
14 iManufacturer 1 00 no manufacturer string (default)
[01] manufacturer string enabled
(using an external EEPROM)
15 iProduct 1 00 no product string (default)
[02] product string enabled
(using an external EEPROM)
16 iSerialNumber 1 00 no serial number string
17 bNumConfigurations 1 01 one configuration