lan9512 Standard Microsystems Corp., lan9512 Datasheet - Page 31

• Manufacturer Part Number: lan9512
• Description: Usb Hub With Integrated 10/100 Ethernet Controller
• Manufacturer: Standard Microsystems Corp.

USB Hub with Integrated 10/100 Ethernet Controller
Datasheet
SMSC LAN9512
BITS
BITS
1:0
7:2
3:2
1
0
Upstream USB Electrical Signaling Drive Strength Boost Bit for
Downstream Port 2 (BOOST_IOUT_2)
00 = Normal electrical drive strength
01 = Elevated electrical drive strength (+4% boost)
10 = Elevated electrical drive strength (+8% boost)
11 = Elevated electrical drive strength (+12% boost)
RESERVED
RESERVED
Reset (RESET)
Resets the internal memory back to nRESET assertion default settings.
0 = Normal Run/Idle State
1 = Force a reset of the registers to their default state
Note:
USB Attach and Write Protect (USB_ATTACH)
0 = Device is in configuration state
1 = Hub will signal a USB attach event to an upstream device, and the
internal memory (address range 00h - FEh) is “write-protected” to prevent
unintentional data corruption.
Note:
Table 3.8 Boost_3:2 Register (BOOST32) Format (continued)
During this reset, this bit is automatically cleared to its default value
of 0.
This bit is write once and is only cleared by assertion of the external
nRESET or POR.
Table 3.9 Status/Command Register (STCD) Format
DESCRIPTION
DESCRIPTION
DATASHEET
31
Revision 1.0 (04-20-09)
DEFAULT
DEFAULT
000000b
00b
00b
0b
1b