During receiver address matching, the address matching is performed in hardware and the
LPUART receiver will ignore all characters that do not meet the address match
requirements.
Table 48-2. Receiver Wakeup Options
RWU MA1 | MA2 MATCFG WAKE:RWUID Receiver Wakeup
0 0 X X Normal operation
1 0 00 00 Receiver wakeup on
idle line, IDLE flag not
set
1 0 00 01 Receiver wakeup on
idle line, IDLE flag set
1 0 00 10 Receiver wakeup on
address mark
1 1 11 X0 Receiver wakeup on
data match
0 1 00 X0 Address mark address
match, IDLE flag not set
for discarded
characters
0 1 00 X1 Address mark address
match, IDLE flag set for
discarded characters
0 1 01 X0 Idle line address match
0 1 10 X0 Address match on and
address match off,
IDLE flag not set for
discarded characters
0 1 10 X1 Address match on and
address match off,
IDLE flag set for
discarded characters
48.3.3.2.1 Idle-line wakeup
When wake is cleared, the receiver is configured for idle-line wakeup. In this mode,
LPUART_CTRL[RWU] is cleared automatically when the receiver detects a full
character time of the idle-line level. The LPUART_CTRL[M] and
LPUART_BAUD[M10] control bit selects 8-bit to 10-bit data mode and the
LPUART_BAUD[SBNS] bit selects 1-bit or 2-bit stop bit number that determines how
many bit times of idle are needed to constitute a full character time, 10 to 13 bit times
because of the start and stop bits.
When LPUART_CTRL[RWU] is one and LPUART_STAT[RWUID] is zero, the idle
condition that wakes up the receiver does not set the LPUART_STAT[IDLE] flag. The
receiver wakes up and waits for the first data character of the next message that sets the
Functional description
K22F Sub-Family Reference Manual, Rev. 4, 08/2016
1328 NXP Semiconductors