
UARTx_SFIFO field descriptions (continued)
Field
Description
0
Transmit buffer is not empty.
1
Transmit buffer is empty.
6
RXEMPT
Receive Buffer/FIFO Empty
Asserts when there is no data in the receive FIFO/Buffer. This field does not take into account data that is
in the receive shift register.
0
Receive buffer is not empty.
1
Receive buffer is empty.
5–3
Reserved
This field is reserved.
This read-only field is reserved and always has the value 0.
2
RXOF
Receiver Buffer Overflow Flag
Indicates that more data has been written to the receive buffer than it can hold. This field will assert
regardless of the value of CFIFO[RXOFE]. However, an interrupt will be issued to the host only if
CFIFO[RXOFE] is set. This flag is cleared by writing a 1.
0
No receive buffer overflow has occurred since the last time the flag was cleared.
1
At least one receive buffer overflow has occurred since the last time the flag was cleared.
1
TXOF
Transmitter Buffer Overflow Flag
Indicates that more data has been written to the transmit buffer than it can hold. This field will assert
regardless of the value of CFIFO[TXOFE]. However, an interrupt will be issued to the host only if
CFIFO[TXOFE] is set. This flag is cleared by writing a 1.
0
No transmit buffer overflow has occurred since the last time the flag was cleared.
1
At least one transmit buffer overflow has occurred since the last time the flag was cleared.
0
RXUF
Receiver Buffer Underflow Flag
Indicates that more data has been read from the receive buffer than was present. This field will assert
regardless of the value of CFIFO[RXUFE]. However, an interrupt will be issued to the host only if
CFIFO[RXUFE] is set. This flag is cleared by writing a 1.
0
No receive buffer underflow has occurred since the last time the flag was cleared.
1
At least one receive buffer underflow has occurred since the last time the flag was cleared.
47.3.19 UART FIFO Transmit Watermark (UARTx_TWFIFO)
This register provides the ability to set a programmable threshold for notification of
needing additional transmit data. This register may be read at any time but must be
written only when C2[TE] is not set. Changing the value of the watermark will not clear
the S1[TDRE] flag.
Address: Base a 13h offset
Bit
7
6
5
4
3
2
1
0
Read
Write
Reset
0
0
0
0
0
0
0
0
Chapter 47 Universal Asynchronous Receiver/Transmitter (UART)
K22F Sub-Family Reference Manual, Rev. 4, 08/2016
NXP Semiconductors
1245
Содержание K22F series
Страница 2: ...K22F Sub Family Reference Manual Rev 4 08 2016 2 NXP Semiconductors...
Страница 150: ...Private Peripheral Bus PPB memory map K22F Sub Family Reference Manual Rev 4 08 2016 150 NXP Semiconductors...
Страница 168: ...Module clocks K22F Sub Family Reference Manual Rev 4 08 2016 168 NXP Semiconductors...
Страница 198: ...Security Interactions with other Modules K22F Sub Family Reference Manual Rev 4 08 2016 198 NXP Semiconductors...
Страница 258: ...Functional description K22F Sub Family Reference Manual Rev 4 08 2016 258 NXP Semiconductors...
Страница 292: ...Functional description K22F Sub Family Reference Manual Rev 4 08 2016 292 NXP Semiconductors...
Страница 398: ...Functional description K22F Sub Family Reference Manual Rev 4 08 2016 398 NXP Semiconductors...
Страница 628: ...Initialization and application information K22F Sub Family Reference Manual Rev 4 08 2016 628 NXP Semiconductors...
Страница 740: ...Initialization Application Information K22F Sub Family Reference Manual Rev 4 08 2016 740 NXP Semiconductors...
Страница 750: ...Functional description K22F Sub Family Reference Manual Rev 4 08 2016 750 NXP Semiconductors...
Страница 816: ...Application information K22F Sub Family Reference Manual Rev 4 08 2016 816 NXP Semiconductors...
Страница 866: ...Initialization Application Information K22F Sub Family Reference Manual Rev 4 08 2016 866 NXP Semiconductors...
Страница 890: ...Application information K22F Sub Family Reference Manual Rev 4 08 2016 890 NXP Semiconductors...
Страница 1028: ...Initialization Procedure K22F Sub Family Reference Manual Rev 4 08 2016 1028 NXP Semiconductors...
Страница 1040: ...Example configuration for chained timers K22F Sub Family Reference Manual Rev 4 08 2016 1040 NXP Semiconductors...
Страница 1118: ...Device mode IRC48 operation K22F Sub Family Reference Manual Rev 4 08 2016 1118 NXP Semiconductors...
Страница 1122: ...USB Voltage Regulator Module Signal Descriptions K22F Sub Family Reference Manual Rev 4 08 2016 1122 NXP Semiconductors...
Страница 1180: ...Initialization application information K22F Sub Family Reference Manual Rev 4 08 2016 1180 NXP Semiconductors...
Страница 1302: ...Application information K22F Sub Family Reference Manual Rev 4 08 2016 1302 NXP Semiconductors...
Страница 1374: ...Functional description K22F Sub Family Reference Manual Rev 4 08 2016 1374 NXP Semiconductors...