hfnum
This register contains the free space information for the Periodic TxFIFO and the Periodic Transmit Request Queue
| Module Instance | Base Address | Register Address |
|---|---|---|
| usb0 | 0xFFB00000 | 0xFFB00408 |
| usb1 | 0xFFB40000 | 0xFFB40408 |
Offset: 0x408
Access: RO
| Bit Fields | |||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 31 | 30 | 29 | 28 | 27 | 26 | 25 | 24 | 23 | 22 | 21 | 20 | 19 | 18 | 17 | 16 |
frrem RO 0x0 |
|||||||||||||||
| 15 | 14 | 13 | 12 | 11 | 10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 |
frnum RO 0x3FFF |
|||||||||||||||
hfnum Fields
| Bit | Name | Description | Access | Reset | ||||||
|---|---|---|---|---|---|---|---|---|---|---|
| 31:16 | frrem | Indicates the amount of time remaining in the current microframe (HS) or Frame (FS/LS), in terms of PHY clocks. This field decrements on each PHY clock. When it reaches zero, this field is reloaded with the value in the Frame Interval register and a new SOF is transmitted on the USB. |
RO | 0x0 | ||||||
| 15:0 | frnum | This field increments when a new SOF is transmitted on the USB, and is reset to 0 when it reaches 0x3FFF. Reads Return the Frame number value.
|
RO | 0x3FFF |