flag is often used in systems with modems to determine when it is safe to turn off the
modem. If the transmit complete interrupt enable (LPUART_CTRL[TCIE]) bit is set, a
hardware interrupt is requested when LPUART_STAT[TC] is set. Instead of hardware
interrupts, software polling may be used to monitor the LPUART_STAT[TDRE] and
LPUART_STAT[TC] status flags if the corresponding LPUART_CTRL[TIE] or
LPUART_CTRL[TCIE] local interrupt masks are cleared.
When a program detects that the receive data register is full (LPUART_STAT[RDRF] =
1), it gets the data from the receive data register by reading LPUART_DATA. The
LPUART_STAT[RDRF] flag is cleared by reading LPUART_DATA.
The IDLE status flag includes logic that prevents it from getting set repeatedly when the
LPUART_RX line remains idle for an extended period of time. IDLE is cleared by
writing 1 to the LPUART_STAT[IDLE] flag. After LPUART_STAT[IDLE] has been
cleared, it cannot become set again until the receiver has received at least one new
character and has set LPUART_STAT[RDRF].
If the associated error was detected in the received character that caused
LPUART_STAT[RDRF] to be set, the error flags - noise flag (LPUART_STAT[NF]),
framing error (LPUART_STAT[FE]), and parity error flag (LPUART_STAT[PF]) - are
set at the same time as LPUART_STAT[RDRF]. These flags are not set in overrun cases.
If LPUART_STAT[RDRF] was already set when a new character is ready to be
transferred from the receive shifter to the receive data buffer, the overrun
(LPUART_STAT[OR]) flag is set instead of the data along with any associated NF, FE,
or PF condition is lost.
If the received character matches the contents of MATCH[MA1] and/or MATCH[MA2]
then the LPUART_STAT[MA1F] and/or LPUART_STAT[MA2F] flags are set at the
same time that LPUART_STAT[RDRF] is set.
At any time, an active edge on the LPUART_RX serial data input pin causes the
LPUART_STAT[RXEDGIF] flag to set. The LPUART_STAT[RXEDGIF] flag is
cleared by writing a 1 to it. This function depends on the receiver being enabled
(LPUART_CTRL[RE] = 1).
Functional description
KL27 Sub-Family Reference Manual , Rev. 5, 01/2016
676
Freescale Semiconductor, Inc.
Содержание MKL27Z128VFM4
Страница 2: ...KL27 Sub Family Reference Manual Rev 5 01 2016 2 Freescale Semiconductor Inc...
Страница 54: ...AWIC introduction KL27 Sub Family Reference Manual Rev 5 01 2016 54 Freescale Semiconductor Inc...
Страница 100: ...Module operation in low power modes KL27 Sub Family Reference Manual Rev 5 01 2016 100 Freescale Semiconductor Inc...
Страница 142: ...Functional description KL27 Sub Family Reference Manual Rev 5 01 2016 142 Freescale Semiconductor Inc...
Страница 248: ...Memory map and register descriptions KL27 Sub Family Reference Manual Rev 5 01 2016 248 Freescale Semiconductor Inc...
Страница 256: ...Memory map register descriptions KL27 Sub Family Reference Manual Rev 5 01 2016 256 Freescale Semiconductor Inc...
Страница 262: ...Initialization application information KL27 Sub Family Reference Manual Rev 5 01 2016 262 Freescale Semiconductor Inc...
Страница 292: ...Functional description KL27 Sub Family Reference Manual Rev 5 01 2016 292 Freescale Semiconductor Inc...
Страница 324: ...Functional Description KL27 Sub Family Reference Manual Rev 5 01 2016 324 Freescale Semiconductor Inc...
Страница 390: ...Application information KL27 Sub Family Reference Manual Rev 5 01 2016 390 Freescale Semiconductor Inc...
Страница 422: ...Functional description KL27 Sub Family Reference Manual Rev 5 01 2016 422 Freescale Semiconductor Inc...
Страница 432: ...Initialization Application Information KL27 Sub Family Reference Manual Rev 5 01 2016 432 Freescale Semiconductor Inc...
Страница 442: ...Functional description KL27 Sub Family Reference Manual Rev 5 01 2016 442 Freescale Semiconductor Inc...
Страница 512: ...Functional description KL27 Sub Family Reference Manual Rev 5 01 2016 512 Freescale Semiconductor Inc...
Страница 610: ...Initialization application information KL27 Sub Family Reference Manual Rev 5 01 2016 610 Freescale Semiconductor Inc...
Страница 646: ...Initialization application information KL27 Sub Family Reference Manual Rev 5 01 2016 646 Freescale Semiconductor Inc...
Страница 744: ...Application information KL27 Sub Family Reference Manual Rev 5 01 2016 744 Freescale Semiconductor Inc...
Страница 784: ...Application Information KL27 Sub Family Reference Manual Rev 5 01 2016 784 Freescale Semiconductor Inc...
Страница 830: ...Functional description KL27 Sub Family Reference Manual Rev 5 01 2016 830 Freescale Semiconductor Inc...
Страница 850: ...Application information KL27 Sub Family Reference Manual Rev 5 01 2016 850 Freescale Semiconductor Inc...
Страница 886: ...Functional description KL27 Sub Family Reference Manual Rev 5 01 2016 886 Freescale Semiconductor Inc...