USB Device Controller
1581
SPNU503C – March 2018
Copyright © 2018, Texas Instruments Incorporated
Universal Serial Bus (USB)
29.3.1.14 Non-ISO Endpoint Interrupt Status Register (EPN_STAT)
This read-only register identifies the non-ISO endpoint causing an EPn interrupt. A write into it is denied.
NOTE:
If a nontransparent transaction occurs before a previous one on another endpoint in the
same direction that has been handled, the second interrupt is asserted only after the USB
device controller clears the first one and EPN_STAT is updated with the corresponding
interrupt assertion.
Figure 29-41. Non-ISO Endpoint Interrupt Status Register (EPN_STAT) [address = FCF78A1Ah]
15
12
11
8
Reserved
EPn_RX_IT_SRC
R-0
R-0
7
4
3
0
Reserved
EPn_TX_IT_SRC
R-0
R-0
LEGEND: R = Read only; -
n
= value at reset
Table 29-45. Non-ISO Endpoint Interrupt Status Register (EPN_STAT) Field Descriptions
Bit
Field
Value
Description
15-12
Reserved
0
Reserved
11-8
EPn_RX_IT_SRC
The receive endpoint interrupt source (non-ISO) bit only concerns non-ISO endpoints. When the
IRQ_SRC.EPn_RX flag is set, the endpoint causing the interrupt condition is encoded in these four
register bits. When the IRQ_SRC.EPn_RX flag is cleared, the four bits read as 0.
0
No receive endpoint interrupt is pending.
1h
EP1
:
:
Fh
EP15
Values after system reset or USB reset are low (all four bits).
7-4
Reserved
0
Reserved
3-0
EPn_TX_IT_SRC
Transmit endpoint interrupt source (non-ISO) bit only concerns non-ISO endpoints. When the
IRQ_SRC.EPn_TX flag is set, the endpoint that causes this flag to be set is encoded in these four
register bits. When the IRQ_SRC.EPn_TX flag is cleared, the four bits read as 0.
0
No transmit endpoint interrupt is pending.
1h
EP1
:
:
Fh
EP15
Values after system reset or USB reset are low (all 4 bits).