
Philips Semiconductors
ISP1122
USB stand-alone hub
Product specification
Rev. 03 — 29 March 2000
12 of 48
9397 750 07002
© Philips Electronics N.V. 2000. All rights reserved.
9.
Host requests
The ISP1122 handles all standard USB requests from the host via control endpoint 0.
The control endpoint can handle a maximum of 64 bytes per transfer.
Remark: Please note that the USB data transmission order is Least Significant Bit
(LSB) first. In the following tables multi-byte variables are displayed least significant
byte first.
9.1 Standard requests
shows the supported standard USB requests. Some requests are explicitly
unsupported. All other requests will be responded with a STALL packet.
Table 6:
Status Change byte: bit allocation
Bit
Symbol
Description
0
Hub SC
a logic 1 indicates a status change on the hub’s upstream port
1
Port 1 SC
a logic 1 indicates a status change on downstream port 1
2
Port 2 SC
a logic 1 indicates a status change on downstream port 2
3
Port 3 SC
a logic 1 indicates a status change on downstream port 3
4
Port 4 SC
a logic 1 indicates a status change on downstream port 4
5
Port 5 SC
a logic 1 indicates a status change on downstream port 5
6
reserved
not used
7
reserved
not used
Table 7:
Standard USB requests
Request name
bmRequestType
byte 0 [7:0]
(Bin)
bRequest
byte 1
(Hex)
wValue
byte 2, 3
(Hex)
wIndex
byte 4, 5
(Hex)
wLength
byte 6, 7
(Hex)
Data
Address
Set Address
X000 0000
05
address
00, 00
00, 00
none
Configuration
Get Configuration
1000 0000
08
00, 00
00, 00
01, 00
configuration
value = 01H
Set Configuration (0)
X000 0000
09
00, 00
00, 00
00, 00
none
Set Configuration (1)
X000 0000
09
01, 00
00, 00
00, 00
none
Descriptor
Get Configuration
Descriptor
1000 0000
06
00, 02
00, 00
length
configuration,
interface and
endpoint
descriptors
Get Device Descriptor
1000 0000
06
00, 01
00, 00
length
device
descriptor
Get String Descriptor (0)
1000 0000
06
03, 00
00, 00
length
language ID
string
Get String Descriptor (1)
1000 0000
06
03, 01
00, 00
length
manufacturer
string
Get String Descriptor (2)
1000 0000
06
03, 02
00, 00
length
product string