Freescale Semiconductor MPC8313E PowerQUICC II Pro Family Reference Manual page 958

Universal Serial Bus Interface
Bits Name
5 OCC Over-current change. This bit gets set when there is a change to over-current active. Software clears this bit
by writing a one to this bit position.
Host/OTG mode:
• The user can provide over-current detection to the USB n _PWRFAULT signal for this condition.
Device mode:
• This bit must always be 0.
1 Over current detect.
0 No over current.
4 OCA Over-current active. This bit will automatically transition from one to zero when the over current condition is
removed.
Host/OTG mode:
• The user can provide over-current detection to the USB n _PWRFAULT signal for this condition.
Device mode:
• This bit must always be 0.
1 Port currently in over-current condition.
0 Port not in over-current condition.
3 PEC Port enable/disable change.
For the root hub, this bit gets set only when a port is disabled due to disconnect on the port or due to the
appropriate conditions existing at the EOF2 point (See Chapter 11 of the USB Specification). Software clears
this by writing a one to it.[
In device mode:
• The device port is always enabled. (This bit will be zero.)
1 Port disabled.
0 No change.
This field is zero if Port Power(PP) is zero.
2 PE Port enabled/disabled.
Host mode:
• Ports can only be enabled by the controller as a part of the reset and enable. Software cannot enable a port
by writing a one to this field. Ports can be disabled by either a fault condition (disconnect event or other fault
condition) or by the host software. Note that the bit status does not change until the port state actually
changes. There may be a delay in disabling or enabling a port due to other host and bus events.
• When the port is disabled, (0) downstream propagation of data is blocked except for reset.
• This field is zero if Port Power(PP) is zero in host mode.
Device mode:
• The device port is always enabled. (This bit will be one.)
MPC8313E PowerQUICC™ II Pro Integrated Processor Family Reference Manual, Rev. 2
16-30
Table 16-23. PORTSC Register Field Descriptions (continued)
Description
Freescale Semiconductor