Datasheet

39.6.13 Device Frame Number Register
Name: USBHS_DEVFNUM
Offset: 0x0020
Reset: 0x00000000
Property: Read-only
Bit 31 30 29 28 27 26 25 24
Access
Reset
Bit 23 22 21 20 19 18 17 16
Access
Reset
Bit 15 14 13 12 11 10 9 8
FNCERR FNUM[10:5]
Access
Reset 0 0 0 0 0 0 0
Bit 7 6 5 4 3 2 1 0
FNUM[4:0] MFNUM[2:0]
Access
Reset 0 0 0 0 0 0 0 0
Bit 15 – FNCERR Frame Number CRC Error
Value Description
0
Cleared upon receiving a USB reset.
1
Set when a corrupted frame number (or microframe 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
This field contains the 1
1-bit frame number information. It is provided in the last received SOF packet.
This field is cleared upon receiving a USB reset.
FNUM is updated even if a corrupted SOF is received.
Bits 2:0 – MFNUM[2:0] Micro Frame Number
This field contains the 3-bit micro frame number information. It is provided in the last received MSOF packet.
This field is cleared at the beginning of each start of frame (SOF interrupt) or upon receiving a USB reset.
MFNUM is updated even if a corrupted MSOF is received.
SAM E70/S70/V70/V71 Family
USB High-Speed Interface (USBHS)
©
2019 Microchip Technology Inc.
Datasheet
DS60001527D-page 827