LM3S3749 Datasheet, PDF (649/898 Pages) Texas Instruments – Stellaris® LM3S3749 Microcontroller

Stellaris® LM3S3749 Microcontroller
Register 3: USB Transmit Interrupt Status (USBTXIS), offset 0x002
Important: This register is read-sensitive. See the register description for details.
Host
Device
USBTXIS is a 16-bit read-only register that indicates which interrupts are currently active for endpoint
0 and the transmit endpoints 1–3. The meaning of the EPn bits in this register are based on the
mode of the device. The EP1, EP2 and EP3 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.
USB Transmit Interrupt Status (USBTXIS)
Base 0x4005.0000
Offset 0x002
Type RO, reset 0x0000
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
reserved
EP3
EP2
EP1
EP0
Type RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
Reset
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Bit/Field
15:4
3
Name
reserved
EP3
Type
RO
RO
Reset
0x00
0
Description
Software should not rely on the value of a reserved bit. To provide
compatibility with future products, the value of a reserved bit should be
preserved across a read-modify-write operation.
TX Endpoint 3 Interrupt
Value Description
0 No interrupt.
1 The Endpoint 3 transmit interrupt is asserted.
2
EP2
RO
0
TX Endpoint 2 Interrupt
Same description as EP15.
1
EP1
RO
0
TX Endpoint 1 Interrupt
Same description as EP15.
0
EP0
RO
0
TX and RX Endpoint 0 Interrupt
Value Description
0 No interrupt.
1 The Endpoint 0 transmit and receive interrupt is asserted.
November 17, 2011
649
Texas Instruments-Production Data