Datasheet

USB 2.0 Hi-Speed 7-Port Hub Controller
Datasheet
Revision 2.8 (09-17-12) 22 SMSC USB2517
DATASHEET
7.2.1.5 Register 04h: Device ID (LSB)
7.2.1.6 Register 05h: Device ID (MSB)
7.2.1.7 Register 06h: CONFIG_BYTE_1
BIT
NUMBER BIT NAME DESCRIPTION
7:0 DID_LSB Least Significant Byte of the Device ID. This is a 16-bit device release
number in BCD format (assigned by OEM). This field is set by the OEM
using either the SMBus or EEPROM interface options.
BIT
NUMBER BIT NAME DESCRIPTION
7:0 DID_MSB Most Significant Byte of the Device ID. This is a 16-bit device release
number in BCD format (assigned by OEM). This field is set by the OEM
using either the SMBus or EEPROM interface options.
BIT
NUMBER BIT NAME DESCRIPTION
7 SELF_BUS_PWR Self or Bus Power: Selects between Self- and Bus-Powered operation.
The Hub is either Self-Powered (draws less than 2mA of upstream bus
power) or Bus-Powered (limited to a 100mA maximum of upstream power
prior to being configured by the host controller).
When configured as a Bus-Powered device, the SMSC Hub consumes less
than 100mA of current prior to being configured. After configuration, the Bus-
Powered SMSC Hub (along with all associated hub circuitry, any embedded
devices if part of a compound device, and 100mA per externally available
downstream port) must consume no more than 500mA of upstream VBUS
current. The current consumption is system dependent, and the OEM must
ensure that the USB 2.0 specifications are not violated.
When configured as a Self-Powered device, <1mA of upstream VBUS
current is consumed and all ports are available, with each port being capable
of sourcing 500mA of current.
This field is set by the OEM using either the SMBus or EEPROM interface
options.
Please see the description under Dynamic Power for the self/bus power
functionality when dynamic power switching is enabled.
0 = Bus-Powered operation
1 = Self-Powered operation
Note: If Dynamic Power Switching is enabled, this bit is ignored and the
LOCAL_PWR pin is used to determine if the hub is operating from
self or bus power.
6 Reserved Reserved
5 HS_DISABLE High Speed Disable: Disables the capability to attach as either a High/Full-
speed device, and forces attachment as Full-speed only (i.e. no Hi-Speed
support).
0 = High-/Full-Speed
1 = Full-Speed-Only (Hi-Speed disabled!)