ISP1160
Embedded USB Host Controller
Philips Semiconductors
Table 35: HcRshPortStatus[1:2] register: bit description…continued
Bit
Symbol
Description
2
PSS
On read—PortSuspendStatus: This bit indicates whether the port
is suspended or in the resume sequence. It is set by a
SetSuspendState write and cleared when
PortSuspendStatusChange is set at the end of the resume
interval. This bit cannot be set if CurrentConnectStatus is cleared.
This bit is also cleared when PortResetStatusChange is set at the
end of the port reset or when the HC is placed in the USBResume
state. If an upstream resume is in progress, it should propagate to
the HC.
0 — port is not suspended
1 — port is suspended
On write—SetPortSuspend: The HCD sets
bit PortSuspendStatus by writing a logic 1 to this bit. Writing a
logic 0 has no effect. If CurrentConnectStatus is cleared, this write
does not set PortSuspendStatus; instead it sets
ConnectStatusChange. This informs the driver that it attempted to
suspend a disconnected port.
1
PES
On read—PortEnableStatus: This bit indicates whether the port is
enabled or disabled. The Root Hub may clear this bit when an
overcurrent condition, disconnect event, switched-off power, or
operational bus error such as babble is detected. This change also
causes PortEnabledStatusChange to be set. The HCD sets this bit
by writing SetPortEnable and clears it by writing ClearPortEnable.
This bit cannot be set when CurrentConnectStatus is cleared. This
bit is also set at the completion of a port reset when
ResetStatusChange is set or port is suspended when
SuspendStatusChange is set.
0 — port is disabled
1 — port is enabled
On write—SetPortEnable: The HCD sets PortEnableStatus by
writing a logic 1. Writing a logic 0 has no effect. If
CurrentConnectStatus is cleared, this write does not set
PortEnableStatus, but instead sets ConnectStatusChange. This
informs the driver that it attempted to enable a disconnected port.
0
CCS
On read—CurrentConnectStatus: This bit reflects the current
state of the downstream port.
0 — no device connected
1 — device connected
On write—ClearPortEnable: The HCD writes a logic 1 to this bit to
clear bit PortEnableStatus. Writing a logic 0 has no effect.
CurrentConnectStatus is not affected by any write.
Remark: This bit always reads logic 1 when the attached device is
nonremovable (DeviceRemoveable[NDP]).
9397 750 11371
© Koninklijke Philips Electronics N.V. 2003. All rights reserved.
Product data
Rev. 04 — 04 July 2003
56 of 88
NXP [ NXP ]
