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NUC970 Technical Reference Manual
Publication Release Date: Dec. 15, 2015
- 733 -
Revision V1.30
NUC97
0
T
E
CHNIC
A
L
RE
F
E
RE
N
CE
MA
NUA
L
USB Frame Index Register (UFINDR)
Register
Offset
R/W
Description
Reset Value
UFINDR
0x02C
R/W
USB Frame Index Register
0x0000_0000
31
30
29
28
27
26
25
24
Reserved
23
22
21
20
19
18
17
16
Reserved
15
14
13
12
11
10
9
8
Reserved
FI
7
6
5
4
3
2
1
0
FI
Bits
Description
[31:14]
Reserved
Reserved.
[13:0]
FI
Frame Index
The value in this register increment at the end of each time frame (e.g. micro-frame). Bits
[N:3] are used for the Frame List current index. This means that each location of the frame
list is accessed 8 times (frames or micro-frames) before moving to the next index. The
following illustrates values of N based on the value of the Frame List Size field in the
USBCMD register.
FLSZ (UCMDR[3:2] Number Elements N
0x0 1024 12
0x1 512 11
0x2 256 10
0x3 Reserved