Register Map
13-30
13.2.10.2
Time Stamp OK(TS_OK)
This bit indicates that the time stamp in the TS field is valid for the current
frame. It returns a 1 if a valid SOF packet was received from the USB host and
a 0 otherwise.
0: Time stamp is invalid.
1: Time stamp is valid.
Value after local host or USB reset is low.
13.2.10.3
Time Stamp Number(TS)
This field returns the time stamp from last USB host valid SOF packet. The
frame number is valid if the TS_OK is 1. In case of a SOF miss, this value is
not updated and TS_OK is cleared.
Value after local host or USB reset is low (all 11 bits).
13.2.11
Interrupt Enable Register (IRQ_EN)
The read/write interrupt enable register (IRQ_EN) enables all non-DMA
interrupts (control, state changed, isochronous, non-isochronous).
Table 13–12. Interrupt Enable Register (IRQ_EN)
Bit
Name
Description
15–8
–
Reserved
7
SOF_IE
Start-of-frame interrupt enable
6
–
Reserved
5
EPn_RX_IE
Receive endpoint n interrupt enable (non-isochronous)
4
EPn_TX_IE
Transmit endpoint n interrupt enable (non-isochronous)
3
DS_Chg_IE
Device state changed interrupt enable
2–1
–
Reserved
0
EP0_IE
EP0 transactions interrupt enable
When a bit position is set to 1 by the local host, an interrupt is signaled to the
local host if the corresponding IRQ_SRC bit is asserted to 1 by the core, for
any IRQ_SRC bit controlled by this bit. If reset to 0, the interrupt is masked and
not signaled to the local host.
0: Interrupt disabled
1: Interrupt enabled
Value after local host or USB reset is low for all bits except the DS_Chg_IE bit,
which remains unchanged after a reset from USB host.