LAN9514_12 Datasheet, PDF (31/52 Pages) SMSC Corporation – USB 2.0 Hub and 10/100 Ethernet Controller

USB 2.0 Hub and 10/100 Ethernet Controller
Datasheet
Table 3.4 Config Data Byte 1 Register (CFG1) Format
BITS
7
6
5
4
3
DESCRIPTION
Self or Bus Power (SELF_BUS_PWR)
Selects between Self or Bus-Powered operation.
0 = Bus-Powered
1 = Self-Powered
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 USB2.0 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.
RESERVED
High Speed Disable (HS_DISABLE)
Disables the capability to attach as either a High/Full-Speed device, and forces
attachment as Full-Speed only (no High-Speed support).
0 = High-/Full-Speed
1 = Full-Speed-Only (High-Speed disabled)
Multiple TT Enable (MTT_ENABLE)
Enables one transaction translator per port operation.
Selects between a mode where only one transaction translator is available for all ports
(Single-TT), or each port gets a dedicated transaction translator (Multi-TT) {Note: The
host may force Single-TT mode only}.
0 = Single TT for all ports.
1 = One TT per port (multiple TT's supported)
EOP Disable (EOP_DISABLE)
Disables EOP generation of EOF1 when in Full-Speed mode. During FS operation
only, this permits the Hub to send EOP if no downstream traffic is detected at EOF1.
See Section 11.3.1 of the USB 2.0 Specification for additional details.
Note: Generation of an EOP at the EOF1 point may prevent a Host controller
(operating in FS mode) from placing the USB bus in suspend.
0 = An EOP is generated at the EOF1 point if no traffic is detected.
1 = EOP generation at EOF1 is disabled (note: this is normal USB operation).
Note:
This is a rarely used feature in the PC environment, existing drivers may not
have been thoroughly debugged with this feature enabled. It is included
because it is a permitted feature in Chapter 11 of the USB specification.
DEFAULT
1b
0b
0b
1b
1b
SMSC LAN9514/LAN9514i
31
DATASHEET
Revision 1.2 (02-29-12)