FW82801EB Intel, FW82801EB Datasheet - Page 225

• Manufacturer Part Number: FW82801EB
• Manufacturer: Intel

Specifications of FW82801EB

• Lead Free Status / RoHS Status: Not Compliant

5.20.8.3
5.20.8.4
5.20.9
Intel
®
82801EB ICH5 / 82801ER ICH5R Datasheet
Effect of Resets on Port-Routing Logic
USB 2.0 Legacy Keyboard Operation
Device Disconnects
The Enhanced Host Controller Interface Specification for Universal Serial Bus, Revision 1.0
describes the details of handling Device Connects in Section 4.2. There are three general scenarios
that are summarized below.
As mentioned above, the Port Routing logic is implemented in the Suspend power well so that
remuneration and re-mapping of the USB ports is not required following entering and exiting a
system sleep state in which the core power is turned off.
The ICH5 must support the possibility of a keyboard downstream from either a full speed/low
speed or a high speed port. The description of the legacy keyboard support is unchanged from
USB 1.1 (See
The EHC provides the basic ability to generate SMIs on an interrupt event, along with more
sophisticated control of the generation of SMIs.
Suspend Well Reset
Core Well Reset
D3-to-D0 Reset
HCRESET
1. Configure Flag = 0 and the device is disconnected
2. Configure Flag = 1 and a full speed/low speed-capable Device is disconnected
3. Configure Flag = 1 and a high speed-capable Device is disconnected
— In this case, the UHC is the owner of the port both before and after the disconnect occurs.
— In this case, the UHC is the owner of the port before the disconnect occurs. The
— In this case, the EHC is the owner of the port before, and remains the owner after, the
Reset Event
The EHC (except for the port-routing logic) never sees a device attached. The UHCI
driver handles disconnection process.
disconnect is reported by the UHC and serviced by the associated UHCI driver. The
port-routing logic in the EHC cluster forces the Port Owner bit to 0, indicating that the
EHC owns the unconnected port.
disconnect occurs. The EHCI hardware and driver handle the disconnection process. The
UHC never sees a device attached.
Section
5.19.8).
Effect on Configure Flag
cleared (0)
cleared (0)
no effect
no effect
Effect on Port Owner Bits
no effect
no effect
set (1)
set (1)
Functional Description
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