2-Port USB 2.0 Hub Controller

Datasheet

5.3.9.14Register 0Dh: Max Power For Bus Powered Operation (Reset = 0x00)

BIT

 

 

NUMBER

BIT NAME

DESCRIPTION

 

 

 

7:0

MAX_PWR_BP

Max Power Bus_Powered: Value in 2mA increments that the Hub consumes

 

 

from an upstream port (VBUS) when operating as a bus-powered hub. This

 

 

value includes the hub silicon along with the combined power consumption

 

 

(from VBUS) of all associated circuitry on the board. This value also includes

 

 

the power consumption of a permanently attached peripheral if the hub is

 

 

configured as a compound device, and the embedded peripheral reports

 

 

0mA in its descriptors.

 

 

A value of 50 (decimal) indicates 100mA.

 

 

 

5.3.9.15Register 0Eh: Hub Controller Max Current For Self Powered Operation (Reset = 0x00)

BIT

 

 

NUMBER

BIT NAME

DESCRIPTION

 

 

 

7:0

HC_MAX_C_SP

Hub Controller Max Current Self-Powered: Value in 2mA increments that the

 

 

Hub consumes from an upstream port (VBUS) when operating as a self-

 

 

powered hub. This value includes the hub silicon along with the combined

 

 

power consumption (from VBUS) of all associated circuitry on the board.

 

 

This value does NOT include the power consumption of a permanently

 

 

attached peripheral if the hub is configured as a compound device.

 

 

Note: The USB 2.0 Specification does not permit this value to exceed

 

 

100mA

 

 

A value of 50 (decimal) indicates 100mA, which is the default value.

 

 

 

5.3.9.16Register 0Fh: Hub Controller Max Current For Bus Powered Operation (Reset = 0x00)

BIT

 

 

NUMBER

BIT NAME

DESCRIPTION

 

 

 

7:0

HC_MAX_C_BP

Hub Controller Max Current Bus-Powered: Value in 2mA increments that the

 

 

Hub consumes from an upstream port (VBUS) when operating as a bus-

 

 

powered hub. This value will include the hub silicon along with the combined

 

 

power consumption (from VBUS) of all associated circuitry on the board.

 

 

This value will NOT include the power consumption of a permanently

 

 

attached peripheral if the hub is configured as a compound device.

 

 

A value of 50 (decimal) would indicate 100mA, which is the default value.

 

 

 

5.3.9.17Register 10h: Power-On Time (Reset = 0x00)

BIT

 

 

NUMBER

BIT NAME

DESCRIPTION

 

 

 

7:0

POWER_ON_TIME

Power On Time: The length of time that it 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.

 

 

 

5.3.9.18Undefined Registers

The registers shown in Table 5.4 are the defined registers in the Hub. Reads to undefined registers return 00h. Writes to undefined registers have no effect and do not return an error.

SMSC USB2502

31

Revision 2.3 (08-27-07)

 

DATASHEET