Atmel Xplained Evaluation Board AT32UC3A3-XPLD AT32UC3A3-XPLD 数据表
产品代码
AT32UC3A3-XPLD
725
32072H–AVR32–10/2012
AT32UC3A3
27.8.3.8
Host Frame Number Register
Register Name:
UHFNUM
Access Type:
Read/Write
Offset:
0x0420
Reset Value:
0x00000000
• FLENHIGH: Frame Length
In Full speed mode, this field contains the 8 high-order bits of the 16-bit internal frame counter (at 30MHz, counter length is
30000 to ensure a SOF generation every 1 ms).
In High speed mode, this field contains the 8 high-order bits of the 16-bit internal frame counter (at 30MHz, counter length is
3750 to ensure a SOF generation every 125 us).
• FNUM: Frame Number
This field contains the current SOF number.
This field can be written. In this case, the MFNUM field is reset to zero.
• MFNUM: Micro Frame Number
This field contains the current Micro Frame number (can vary from 0 to 7) updated every 125us.
When operating in full-speed mode, this field is tied to zero.
31
30
29
28
27
26
25
24
-
-
-
-
-
-
-
-
23
22
21
20
19
18
17
16
FLENHIGH
15
14
13
12
11
10
9
8
-
-
FNUM[10:5]
7
6
5
4
3
2
1
0
FNUM[4:0]
MFNUM