Owners manual

Interfaces
H3 Datasheet(Revision1.2) Copyright© 2015 Allwinner Technology Co.,Ltd.All Rights Reserved. Page 512
Because the general TD length is 16 bytes, the memory structure for the
TD must be aligned to a 16-byte boundary. So the lower bits in the PCED,
through bit 0 to bit 3 must be zero in this field.
8.5.2.6.13. HcDoneHead Register(Default Value: 0x00000000)
Offset: 0x430
Register Name: HcDoneHead
Bit
Read/Write
Default/Hex
Description
HCD
HC
31:4
R
R/W
0x0
HcDoneHead[31:4]
When a TD is completed, HC writes the content of HcDoneHead to the
NextTD field of the TD. HC then overwrites the content of HcDoneHead
with the address of this TD. This is set to zero whenever HC writes the
content of this register to HCCA. It also sets the WritebackDoneHead of
HcInterruptStatus.
3:0
R
R
0x0
HcDoneHead[3:0]
Because the general TD length is 16 bytes, the memory structure for the
TD must be aligned to a 16-byte boundary. So the lower bits in the PCED,
through bit 0 to bit 3 must be zero in this field.
8.5.2.6.14. HcFmInterval Register(Default Value: 0x00002EDF)
Offset: 0x434
Register Name: HcFmInterval Register
Bit
Read/Write
Default/Hex
Description
HCD
HC
31
R/W
R
0x0
FrameIntervalToggler
HCD toggles this bit whenever it loads a new value to FrameInterval.
30:16
R/W
R
0x0
FSLargestDataPacket
This field specifies a value which is loaded into the Largest Data Packet
Counter at the beginning of each frame. The counter value represents the
largest amount of data in bits which can be sent or received by the HC in a
single transaction at any given time without causing scheduling overrun.
The field value is calculated by the HCD.
15:14
/
/
0x0
Reserved
13:0
R/W
R
0x2edf
FrameInterval
This specifies the interval between two consecutive SOFs in bit times. The
nominal value is set to be 11,999. HCD should store the current value of
this field before resetting HC. By setting the HostControllerReset field of
HcCommandStatus as this will cause the HC to reset this field to its
nominal value. HCD may choose to restore the stored value upon the
completion of the Reset sequence.
confidential