Integrated USB 2.0 Compatible 4-Port Hub
Datasheet
Revision 2.3 (08-27-07)
30
SMSC USB2504/USB2504A
DATASHEET
5.3.9.9
Register 08h: Configuration Data Byte 2 (Reset = 0x00)
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 High-Speed
support).
0 = High-/Full-Speed.
1 = Full-Speed-Only (High-Speed disabled!)
4
MTT_ENABLE
Multi-TT enable: Enables one transaction translator per port operation.
0 = single TT for all ports.
1 = one TT per port (multiple TT’s supported)
3
EOP_DISABLE
EOP Disable: Disables EOP generation of EOF1 when in Full-Speed mode.
0 = EOP generation is normal.
1 = EOP generation is disabled.
2:1
CURRENT_SNS
Over Current Sense: Indicates whether current sensing is on a port-by-port
basis, or ganged, or no overcurrent sensing.
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!)
0
PORT_PWR
Port Power Switching: Indicates whether port power switching is on a port-
by-port basis or ganged.
0 = Ganged switching (all ports together)
1 = Individual port-by-port switching.
BIT
NUMBER
BIT NAME
DESCRIPTION
7
DYNAMIC
Dynamic Power Enable: Controls the ability for the Hub to transition to Bus-
Powered operation if the local power source is removed (can revert back to
Self-Power if local power source is restored).
0 = No Dynamic auto-switching.
1 = Dynamic Auto-switching capable.
6
Reserved
Reserved
5:4
OC_TIMER
OverCurrent Timer: Over Current Timer delay.
00 = 0.1ms
01 = 2ms
10 = 4ms
11 = 6ms
3
COMPOUND
Compound Device: Designates if Hub is part of a compound device.
0 = No.
1 = Yes, Hub is part of a compound device.
2:0
Reserved
Reserved
BIT
NUMBER
BIT NAME
DESCRIPTION
