Hccontrolheaded register, Register bit assignment, Table 430: hcperiodcurrented – 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
Register bit assignment
HcControlHeadED register
Address: 9010 1020
The HcHeadControlED register contains the physical address of the first endpoint
descriptor of the control list.
Bits
Access
Mnemonic
Reset
Description
D31:04
R
PCED
0h
PeriodCurrentED
Used by the host controller to point to the head of one of
the periodic lists that will be processed in the current
frame. The content of this register is updated by the host
controller after a periodic endpoint has been processed.
The host controller driver can read the content to
determine which endpoint currently is being processed at
the time of the reading.
D03:00
N/A
Not used
0
Must be written to 0.
Table 430: HcPeriodCurrentED
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
CHED
Not used
CHED