TM4C123GH6PM Datasheet, PDF (1191/1409 Pages) Texas Instruments – Tiva Microcontroller

Tiva^™ TM4C123GH6PM Microcontroller
OTG A /
Host
Register 149: USB Host Receive Polling Interval Endpoint 1
(USBRXINTERVAL1), offset 0x11D
Register 150: USB Host Receive Polling Interval Endpoint 2
(USBRXINTERVAL2), offset 0x12D
Register 151: USB Host Receive Polling Interval Endpoint 3
(USBRXINTERVAL3), offset 0x13D
Register 152: USB Host Receive Polling Interval Endpoint 4
(USBRXINTERVAL4), offset 0x14D
Register 153: USB Host Receive Polling Interval Endpoint 5
(USBRXINTERVAL5), offset 0x15D
Register 154: USB Host Receive Polling Interval Endpoint 6
(USBRXINTERVAL6), offset 0x16D
Register 155: USB Host Receive Polling Interval Endpoint 7
(USBRXINTERVAL7), offset 0x17D
USBRXINTERVALn is an 8-bit register that, for interrupt and isochronous transfers, defines the
polling interval for the currently selected receive endpoint. For bulk endpoints, this register defines
the number of frames after which the endpoint should time out on receiving a stream of NAK
responses.
The USBRXINTERVALn register value defines a number of frames, as follows:
Transfer Type
Interrupt
Isochronous
Bulk
Speed
Low-Speed or Full-Speed
Full-Speed
Full-Speed
Valid values (m)
0x01 – 0xFF
0x01 – 0x10
0x02 – 0x10
Interpretation
The polling interval is m frames.
The polling interval is 2^(m-1) frames/microframes.
The NAK Limit is 2^(m-1) frames/microframes. A
value of 0 or 1 disables the NAK timeout
function.
USB Host Receive Polling Interval Endpoint n (USBRXINTERVALn)
Base 0x4005.0000
Offset 0x11D
Type RW, reset 0x00
7
6
5
4
3
2
1
0
TXPOLL / NAKLMT
Type RW
RW
RW
RW
RW
RW
RW
RW
Reset
0
0
0
0
0
0
0
0
Bit/Field
7:0
Name
TXPOLL / NAKLMT
Type
RW
Reset
0x00
Description
RX Polling / NAK Limit
The polling interval for interrupt/isochronous transfers; the NAK limit for
bulk transfers. See table above for valid entries; other values are
reserved.
June 12, 2014
Texas Instruments-Production Data
1191