USB2504 SMSC Corporation, USB2504 Datasheet - Page 33

• Manufacturer Part Number: USB2504
• Description: Integrated USB 2.0 Compatible 4-Port Hub
• Manufacturer: SMSC Corporation

Integrated USB 2.0 Compatible 4-Port Hub
Datasheet
SMSC USB2504/USB2504A
5.3.9.17
5.3.9.18
5.3.9.19
5.4
5.5
NUMBER
BIT
7:0
Default Configuration Option:
Default Strapping Options:
Register 10h: Power-On Time (Reset = 0x00)
Undefined Registers
The registers shown in
return 00h. Writes to undefined registers have no effect and do not return an error.
Reserved Registers
Unless otherwise instructed, only a ‘0’ may be written to all reserved registers or bits.
The SMSC Hub can be configured via its internal default configuration. (please see for specific details
on how to enable default configuration.
Please refer to
selected.
The SMSC Hub can be configured via a combination of internal default values and pin strap options.
Please see
default/pin-strap configuration option.
The strapping option pins only cover a limited sub-set of the configuration options. The internal default
values will be used for the bits & registers that are not controlled by a strapping option pin. Please
refer to
The Amber and Green LED pins are sampled after RESET_N negation, and the logic values are used
to configure the hub if the internal default configuration mode is selected. The implementation shown
below (see
High” configuration, the LED functions with active low signalling, and the PAD will “sink” the current
from the external supply. When a pin is configured with a “Strap Low” configuration, the LED functions
with active high signalling, and the PAD will “source” the current to the external LED.
POWER_ON_TIME
BIT NAME
Table 5.1 on page 20
Figure
Table 4.1, "4-Port Hub Pin Descriptions"
Table 5.1 on page 20
5.1) shows a recommended passive scheme. When a pin is configured with a “Strap
Table 5.4
Power On Time: The length of time that is takes (in 2 ms intervals) from the
time the host initiated power-on sequence begins on a port until power is
good on that port.
for the internal default values that are loaded when this option is selected.
are the defined registers in the Hub. Reads to undefined registers
DATASHEET
for the internal default values that are loaded when this option is
33
DESCRIPTION
for specific details on how to enable the
Revision 2.1 (12-06-06)