AMD SB600 - Manual (Page 58)

©2008 Advanced Micro Devices, Inc. OCHI USB 1.1 and EHCI USB 2.0 Controllers
AMD SB600 Register Reference Manual Proprietary Page 58
HcPeriodCurrentED - 32 bits - [MEM_Reg : 1Ch]
Field Name Bits Default HCD HC Description
Reserved 3:0 Reserved
PCED 31:4 0000000
h
R RW 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.
HcControlHeadED- 32 bits - [MEM_Reg : 20h]
Field Name Bits Default HCD HC Description
Reserved 3:0 Reserved
CHED 31:4 0000000
h
RW R ControlHeadED
HC traverses the Control list starting with the
HcControlHeadED
pointer. The content is loaded
from HCCA during the initialization of HC.
HcControlCurrentED - 32 bits - [MEM_Reg : 24h]
Field Name Bits Default HCD HC Description
Reserved 3:0 Reserved
CCED 31:4 0000000
h
RW RW 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.
HcBulkHeadED - 32 bits - [MEM_Reg : 28h]
Field Name Bits Default HCD HC Description
Reserved 3:0 Reserved
BHED 31:4 0b RW R BulkHeadED
HC traverses the Bulk list starting with the
HcBulkHeadED
pointer. The content is loaded from
HCCA during the initialization of HC.
HcBulkCurrentED - 32 bits - [MEM_Reg : 2Ch]
Field Name Bits Default HCD HC Description
Reserved 3:0 Reserved