SMSC LAN9512 - Manual (Page 29)

USB Hub with Integrated 10/100 Ethernet Controller
Datasheet
SMSC LAN9512 29 Revision 1.0 (04-20-09)
DATASHEET
2:1 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!)
01b
0 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
1b
Table 3.5 Config Data Byte 2 Register (CFG2) Format
BITS DESCRIPTION DEFAULT
7:6 RESERVED 00b
5:4 Over Current Timer (OC_TIMER)
Over Current Timer delay
00 = 50ns
01 = 100ns (This is the recommended value)
10 = 200ns
11 = 400ns
01b
3 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
1b
2:0 RESERVED 000b
Table 3.4 Config Data Byte 1 Register (CFG1) Format (continued)
BITS DESCRIPTION DEFAULT