
USB Registers
1703
SLAU723A – October 2017 – Revised October 2018
Copyright © 2017–2018, Texas Instruments Incorporated
Universal Serial Bus (USB) Controller
27.5.3 USBTXIS Register (Offset = 0x2) [reset = 0x0]
USB Transmit Interrupt Status (USBTXIS)
OTG A / Host
OTG B / Device
USBTXIS is a 16-bit read-only register that indicates which interrupts are currently active for endpoint 0
and the transmit endpoints 1–7. The meaning of the EPn bits in this register is based on the mode of the
device. The EP1 through EP7 bits always indicate that the USB controller is sending data; however, in
Host mode, the bits refer to OUT endpoints; while in Device mode, the bits refer to IN endpoints. The EP0
bit is special in Host and Device modes and indicates that either a control IN or control OUT endpoint has
generated an interrupt.
NOTE:
Bits relating to endpoints that have not been configured always return 0. Note also that all
active interrupts are cleared when this register is read.
USBTXIS is shown in
and described in
Return to
Figure 27-5. USBTXIS Register
7
6
5
4
3
2
1
0
EP7
EP6
EP5
EP4
EP3
EP2
EP1
EP0
R-0x0
R-0x0
R-0x0
R-0x0
R-0x0
R-0x0
R-0x0
R-0x0
Table 27-10. USBTXIS Register Field Descriptions
Bit
Field
Type
Reset
Description
7
EP7
R
0x0
TX Endpoint 7 Interrupt.
0x0 = No interrupt.
0x1 = The Endpoint 7 transmit interrupt is asserted.
6
EP6
R
0x0
TX Endpoint 6 Interrupt.
Same description as EP7.
5
EP5
R
0x0
TX Endpoint 5 Interrupt.
Same description as EP7.
4
EP4
R
0x0
TX Endpoint 4 Interrupt.
Same description as EP7.
3
EP3
R
0x0
TX Endpoint 3 Interrupt.
Same description as EP7.
2
EP2
R
0x0
TX Endpoint 2 Interrupt.
Same description as EP7.
1
EP1
R
0x0
TX Endpoint 1 Interrupt.
Same description as EP7.
0
EP0
R
0x0
TX and RX Endpoint 0 Interrupt.
0x0 = No interrupt.
0x1 = The Endpoint 0 transmit and receive interrupt is asserted.