NXP Semiconductors Kinetis KE1xZ256, Reference Manual

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character time of idle. When LPUART_CTRL[ILT] is set, the idle bit counter does not
start until after the stop bit time, so the idle detection is not affected by the data in the last
character of the previous message.
46.4.3.2.2 Address-mark wakeup
When LPUART_CTRL[WAKE] is set, the receiver is configured for address-mark
wakeup. In this mode, LPUART_CTRL[RWU] is cleared automatically when the
receiver detects a logic 1 in the most significant bit of a received character.
Address-mark wakeup allows messages to contain idle characters, but requires the MSB
be reserved for use in address frames. The logic 1 in the MSB of an address frame clears
the LPUART_CTRL[RWU] bit before the stop bits are received and sets the
LPUART_STAT[RDRF] flag. In this case, the character with the MSB set is received
even though the receiver was sleeping during most of this character time.
46.4.3.2.3 Data match wakeup
When LPUART_CTRL[RWU] is set and LPUART_BAUD[MATCFG] equals 11, the
receiver is configured for data match wakeup. In this mode, LPUART_CTRL[RWU] is
cleared automatically when the receiver detects a character that matches MATCH[MA1]
field when BAUD[MAEN1] is set, or that matches MATCH[MA2] when
BAUD[MAEN2] is set.
46.4.3.2.4 Address Match operation
Address match operation is enabled when the LPUART_BAUD[MAEN1] or
LPUART_BAUD[MAEN2] bit is set and LPUART_BAUD[MATCFG] is equal to 00. In
this function, a character received by the RXD pin with a logic 1 in the bit position
immediately preceding the stop bit is considered an address and is compared with the
associated MATCH[MA1] or MATCH[MA2] field. The character is only transferred to
the receive buffer, and LPUART_STAT[RDRF] is set, if the comparison matches. All
subsequent characters received with a logic 0 in the bit position immediately preceding
the stop bit are considered to be data associated with the address and are transferred to the
receive data buffer. If no marked address match occurs then no transfer is made to the
receive data buffer, and all following characters with logic zero in the bit position
immediately preceding the stop bit are also discarded. If both the
LPUART_BAUD[MAEN1] and LPUART_BAUD[MAEN2] bits are negated, the
receiver operates normally and all data received is transferred to the receive data buffer.
Address match operation functions in the same way for both MATCH[MA1] and
MATCH[MA2] fields.
Chapter 46 Low Power Universal Asynchronous Receiver/Transmitter (LPUART)
Kinetis KE1xZ256 Sub-Family Reference Manual, Rev. 3, 07/2018
NXP Semiconductors 1213