Datasheet

1155
SAM3X / SAM3A [DATASHEET]
Atmel-11057C-ATARM-SAM3X-SAM3A-Datasheet_23-Mar-15
39.6.3.8 Host Frame Number Register
Name: UOTGHS_HSTFNUM
Address: 0x400AC420
Access: Read-write
• FLENHIGH: Frame Length
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
76543210
FNUM MFNUM