Philips Semiconductors
UM10011_4
ISP1521 Hi-Speed USB Hub Demo Board
© Koninklijke Philips Electronics N.V. 2004. All rights reserved.
User manual
Rev. 04.00 — 17 June 2004
10 of 20
Figure 5-2: Windows Reporting of the Self-Powered Mode
5.8. I
2
C-Bus Interface
The ISP1521 can use either its USB descriptors from the internal ROM, or from an external I
2
C-
Bus
TM
EEPROM or microcontroller. Mode selection is done through jumpers J11and J12 (see
Table 5-3).
Table 5-3: Mode Selection Using J11 and J12
*—Default settings.
An external I
2
C-Bus controller acting as a master can also be used to update hub descriptors
through the CN1 connector.
Note
: The I
2
C-Bus external EEPROM cannot be programmed on-board.
J11
J12
Mode
SCL
SDA
ON ON
Internal
ROM LOW LOW
OFF OFF
I
2
C-Bus EEPROM*
HIGH
HIGH
