39.8.2.4. Device Frame Number
Name:
FNUM
Offset:
0x10
Reset:
0x0000
Property:
Read only
Bit
15
14
13
12
11
10
9
8
FNCERR
FNUM[10:5]
Access
R
R
R
R
R
R
R
Reset
0
0
0
0
0
0
0
Bit
7
6
5
4
3
2
1
0
FNUM[4:0]
MFNUM[2:0]
Access
R
R
R
R
R
R
R
R
Reset
0
0
0
0
0
0
0
0
Bit 15 – FNCERR: Frame Number CRC Error
This bit is cleared upon receiving a USB reset.
This bit is set when a corrupted frame number (or micro-frame number) is received.
This bit and the SOF (or MSOF) interrupt bit are updated at the same time.
Bits 13:3 – FNUM[10:0]: Frame Number
These bits are cleared upon receiving a USB reset.
These bits are updated with the frame number information as provided from the last SOF packet even if a
corrupted SOF is received.
Bits 2:0 – MFNUM[2:0]: Micro Frame Number
These bits are cleared upon receiving a USB reset or at the beginning of each Start-of-Frame (SOF
interrupt).
These bits are updated with the micro-frame number information as provided from the last MSOF packet
even if a corrupted MSOF is received.
Atmel SAM L22G / L22J / L22N [DATASHEET]
Atmel-42402E-SAM L22G / L22J / L22N_Datasheet_Complete-07/2016
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