LAN9514_12 Datasheet, PDF (32/52 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 (continued)
BITS
2:1
0
DESCRIPTION
Over Current Sense (CURRENT_SNS)
Selects current sensing on a port-by-port basis, all ports ganged, or none (only for
bus-powered hubs) The ability to support current sensing on a port or ganged basis
is hardware implementation dependent.
00 = Ganged sensing (all ports together)
01 = Individual port-by-port
1x = Over current sensing not supported (must only be used with Bus- Powered
configurations!)
Port Power Switching (PORT_PWR)
Enables power switching on all ports simultaneously (ganged), or port power is
individually switched on and off on a port by port basis (individual). The ability to
support power enabling on a port or ganged basis is hardware implementation
dependent.
0 = Ganged switching (all ports together)
1 = Individual port by port switching
DEFAULT
01b
1b
Table 3.5 Config Data Byte 2 Register (CFG2) Format
BITS
7:6
5:4
3
2:0
DESCRIPTION
RESERVED
Over Current Timer (OC_TIMER)
Over Current Timer delay
00 = 50ns
01 = 100ns (This is the recommended value)
10 = 200ns
11 = 400ns
Compound Device (COMPOUND)
Allows the OEM to indicate that the Hub is part of a compound (see the USB
Specification for definition) device. The applicable port(s) must also be defined as
having a “Non-Removable Device”.
0 = No
1 = Yes, Hub is part of a compound device
RESERVED
DEFAULT
00b
01b
1b
000b
Revision 1.2 (02-29-12)
32
DATASHEET
SMSC LAN9514/LAN9514i