USB 2.0 Hi-Speed 3-Port Hub Controller Optimized for Portable Applications
Datasheet
8.2
Flex Connect
This feature allows the upstream port to be swapped with downstream physical port 1. Only
downstream port 1 can be swapped physically. Using port remapping, any logical port (number
assignment) can be swapped with the upstream port (non-physical).
Flex Connect is enabled/disabled via two control bits in the
The
FLEXCONNECT configuration bit switches the port, and EN_FLEX_MODE enables the mode.
8.2.1
Port Control
Once EN_FLEX_MODE bit is set, the functions of certain pins change, as outlined below.
If EN_FLEX_MODE is set and FLEXCONNECT is not set:
1. SUSPEND outputs ‘0’ to keep any upstream power controller off
If EN_FLEX_MODE is set and FLEXCONNECT is set:
1. The normal upstream VBUS pin becomes a don’t care
2. SUSPEND becomes PRTPWR1/OCS1_N for the port power controller for the connector port
8.3
Resets
The device has the following chip level reset sources:
8.3.1
Power-On Reset (POR)
A power-on reset occurs whenever power is initially supplied to the device, or if power is removed and
reapplied to the device. A timer within the device will assert the internal reset per the specifications
listed in
8.3.2
External Chip Reset (RESET_N)
A valid hardware reset is defined as assertion of RESET_N, after all power supplies are within
operating range, per the specifications in
While reset is asserted, the device (and its associated external circuitry) enters Standby Mode
and consumes minimal current.
Assertion of RESET_N causes the following:
1. The PHY is disabled and the differential pairs will be in a high-impedance state.
2. All transactions immediately terminate; no states are saved.
3. All internal registers return to the default state.
4. The external crystal oscillator is halted.
5. The PLL is halted.
6. The HSIC Strobe and Data pins are driven low.
SMSC USB3813
53
Revision 1.0 (06-17-13)
DATASHEET
SMSC [ SMSC CORPORATION ]
