Download SH7760 Group USB Host Module Application Note

Table 2.2
Field Definitions for General TD
Name
HC Access
Description
R
R
bufferRounding
If the last packet generated by GTD is short packet, a DataUnderrun
error is generated. When this field is set to 1, a DataUnderrun error is
neglected.
DP
R
Direction/PID
Direction of transfer and PID are set.
Code
00b
01b
10b
11b
DI
R
PID Type
SETUP
OUT
IN
Reserved
Data Direction
to endpoint
to endpoint
from endpoint
DelayInterrupt
The timing of an interrupt (WriteBackDoneHead) generation which is
generated after the TD has been completed is defined. The HC waits
for frames set by this field before generating an interrupt. If setting value
is 0, an interrupt is generated immediately. If the setting value is 1, an
interrupt is generated after waiting for one frame. If setting value is
111b, no interrupt is generated.
T
R/W
DataToggle
Sets the PID (DATA0/DATA1) of data packet by LSb. It is updated after
each successful transmission/reception of a data packet. The MSb of
this bit is 0 when the data toggle value is acquired from the toggleCarry
field in the ED. The MSb of this bit is 1 when the data toggle value is
acquired from this field.
EC
R/W
ErrorCount
For each transmission error, this value is incremented. If ErrorCount is
2 and another transfer error occurs, the error type is recorded in the
ConditionCode field and placed on the Done Queue. When a
transaction completes without error, ErrorCount is reset to 0.
CC
R/W
ConditionCode
Indicates the status of the last transfer generated by GTD.
CBP
R/W
CurrentBufferPointer
Indicates the buffer area for transfer to/from the endpoint. The address
of buffer to be accessed next is always indicated. When
CurrentBufferPointer is 0, data of size 0 will be transferred or the
transfer has been completed.
NextTD
R/W
NextTD
Points the next TD.
BE
R
BufferEnd
Indicates the last address of the buffer area.
Rev. 1.00, 10/03, page 11 of 90