Регистры H616: OHCI Frame Remaining Register

O_HcFmRemaining

9.5.3. OHCI Frame Remaining Register - адрес: 0x5200438 0x5310438 0x5311438 (смещение: 0x0438)

Хост-контроллер USB2.0: список регистров

31 |•|•|•|•|•|•|•|•|•|•|•|•|•|•|•|•| 16
15 |•|•|•|•|•|•|•|•|•|•|•|•|•|•|•|•| 00

FRAME_REMAINING_TOGGLE

Bit 31
R (R/W)
0x0

This bit is loaded from the FrameIntervalToggle field of HcFmInterval whenever FrameRemaining reaches 0.
This bit is used by HCD for the synchronization between FrameInterval and FrameRemaining.

Unused

Bits 30 : 14

FRAME_REMAINING

Bits 13 : 0
R (RW)
0x0

This counter is decremented at each bit time. When it reaches zero, it is reset by loading the FrameInterval value specified in HcFmInterval at the next bit time boundary.
When entering the USBOPERATIONAL state, HC re-loads the content with the FrameInterval of HcFmInterval and uses the updated value from the next SOF.

HCD (HC)

Bit fields structure

typedef union o_hcfmremaining { struct { unsigned frame_remaining : 14; unsigned unused0 : 17; unsigned frame_remaining_toggle : 1; } b; unsigned long w; } O_HcFmRemaining