Datasheet

32.8.5.4 Host Frame Number
Name: FNUM
Offset: 0x10
Reset: 0x0000
Property: PAC Write-Protection
Bit 15 14 13 12 11 10 9 8
FNUM[10:5]
Access
R/W R/W R/W R/W R/W R/W
Reset 0 0 0 0 0 0
Bit 7 6 5 4 3 2 1 0
FNUM[4:0]
Access
R/W R/W R/W R/W R/W
Reset 0 0 0 0 0
Bits 13:3 – FNUM[10:0] Frame Number
These bits contains the current SOF number.
These bits can be written by software to initialize a new frame number value. In this case, at the next
SOF, the FNUM field takes its new value.
As the FNUM register lies across two consecutive byte addresses, writing byte-wise (8-bits) to the FNUM
register may produce incorrect frame number generation. It is recommended to write FNUM register
word-wise (32-bits) or half-word-wise (16-bits).
SAM D21 Family
USB – Universal Serial Bus
© 2018 Microchip Technology Inc.
Datasheet Complete
DS40001882D-page 860