AMD SB600 Technical Reference Manual page 58

Field Name Bits
Reserved 3:0
PCED 31:4
Field Name Bits
Reserved 3:0
CHED 31:4
Field Name Bits
Reserved 3:0
CCED 31:4
Field Name Bits
Reserved 3:0
BHED 31:4
Field Name Bits
Reserved 3:0
©2008 Advanced Micro Devices, Inc.
AMD SB600 Register Reference Manual
HcPeriodCurrentED - 32 bits - [MEM_Reg : 1Ch]
Default HCD HC
0000000 R RW
h
HcControlHeadED- 32 bits - [MEM_Reg : 20h]
Default HCD HC
0000000 RW R
h
HcControlCurrentED - 32 bits - [MEM_Reg : 24h]
Default HCD HC
0000000 RW RW
h
HcBulkHeadED - 32 bits - [MEM_Reg : 28h]
Default HCD HC
0b RW R
HcBulkCurrentED - 32 bits - [MEM_Reg : 2Ch]
Default HCD HC
Description
Reserved
PeriodCurrentED
This is used by HC to point to the head of one of the
Periodic lists which will be processed in the current
Frame. The content of this register is updated by HC
after a periodic ED has been processed. HCD may
read the content in determining which ED is currently
being processed at the time of reading.
Description
Reserved
ControlHeadED
HC traverses the Control list starting with the
HcControlHeadED pointer. The content is loaded
from HCCA during the initialization of HC.
Description
Reserved
ControlCurrentED
This pointer is advanced to the next ED after serving
the present one. HC will continue processing the list
from where it left off in the last Frame. When it
reaches the end of the Control list, HC checks the
ControlListFilled of in HcCommandStatus. If set, it
copies the content of HcControlHeadED to
HcControlCurrentED and clears the bit. If not set, it
does nothing. HCD is allowed to modify this register
only when the ControlListEnable of HcControl is
cleared. When set, HCD only reads the
instantaneous value of this register. Initially, this is set
to zero to indicate the end of the Control list.
Description
Reserved
BulkHeadED
HC traverses the Bulk list starting with the
HcBulkHeadED pointer. The content is loaded from
HCCA during the initialization of HC.
Description
Reserved
OCHI USB 1.1 and EHCI USB 2.0 Controllers
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