Hclsthreshold register, Table 439: hcperiodicstart register – Digi NS9750 User Manual
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U S B C o n t r o l l e r M o d u l e
HcLsThreshold register
Address: 9010 1044
The HcLSThreshold register contains a value used by the host controller to determine
whether to commit to the transfer of a maximum-of-8-byte LS packet before EOF.
Neither the host controller driver not the host controller is allowed to change this
value.
D13:00
R/W
PS
0h
PeriodicStart
Determines when is the earliest time the host controller
should start processing the periodic list.
After a hardware reset, the PS field is cleared. The field is
then set by the host controller driver during the host
controller initialization. The value is calculated as
approximately 10% off from the FrameInterval.
A typical value is
3E67h
. When FrameRemaining reaches
the value specified, processing the periodic lists will have
priority over control/bulk processing. The host controller
starts processing the interrupt list after completing the
current control or bulk transaction in progress.
Bits
Access
Mnemonic
Reset
Description
Table 439: HcPeriodicStart register
13
12
11
10
9
8
7
6
5
4
3
2
1
0
15
14
31
29
28
27
26
25
24
23
22
21
20
19
18
17
16
30
Reserved
LSThreshold(LST)
Reserved