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Philips Semiconductors
ISP1521
Hi-Speed USB hub controller
Product data Rev. 03 — 24 November 2004 27 of 53
9397 750 13702
© Koninklijke Philips Electronics N.V. 2004. All rights reserved.
[1] Value in units of 2 ms.
Table 19: Interface descriptor
Offset
(bytes)
Field name Value (hex) Comments
Full-speed High-speed
0 bLength 09 09 descriptor length=9bytes
1 bDescriptorType 04 04 type = INTERFACE
2 bInterfaceNumber 00 00 -
3 bAlternateSetting 00 00 no alternate setting
4 bNumEndpoints 01 01 status change (interrupt) endpoint
5 bInterfaceClass 09 09 HUB_CLASSCODE
6 bInterfaceSubClass 00 00 HubSubClassCode
7 bInterfaceProtocol 00 00 -
8 bInterface 00 00 no interface string descriptor
Table 20: Endpoint descriptor
Offset
(bytes)
Field name Value (hex) Comments
Full-speed High-speed
0 bLength 07 07 descriptor length=7bytes
1 bDescriptorType 05 05 type = ENDPOINT
2 bEndpointAddress 81 81 endpoint 1 at the address number 1
3 bmAttributes 03 03 interrupt endpoint
4 wMaxPacketSize 01 01 packet size = 1 byte
50000
6 bInterval FF 0C polling interval
Table 21: Hub descriptor
Offset
(bytes)
Field name Value (hex) Comments
Full-speed High-speed
0 bDescLength 09 09 descriptor length=9bytes
1 bDescriptorType 29 29 type = HUB
2 bNbrPorts 07 07 number of enabled downstream facing ports; selectable by
DP/DM strapping
06 06
05 05
04 04
03 03
02 02
3 wHubCharacteristics A9 A9 see Ta bl e 22
40000
5 bPwrOn2PwrGood
[1]
32 32 ganged or individual mode = 100 ms
00 00 no power switching mode=0ms
6 bHubContrCurrent 64 64 -
7 DeviceRemovable 00 00 seven downstream facing ports, no embedded port
8 PortPwrCtrlMask FF FF -