LPUARTx_CTRL field descriptions (continued)
Field
Description
0
MA1F interrupt disabled
1
MA1F interrupt enabled
14
MA2IE
Match 2 Interrupt Enable
0
MA2F interrupt disabled
1
MA2F interrupt enabled
13–11
Reserved
This field is reserved.
This read-only field is reserved and always has the value 0.
10–8
IDLECFG
Idle Configuration
Configures the number of idle characters that must be received before the IDLE flag is set.
000
1 idle character
001
2 idle characters
010
4 idle characters
011
8 idle characters
100
16 idle characters
101
32 idle characters
110
64 idle characters
111
128 idle characters
7
LOOPS
Loop Mode Select
When LOOPS is set, the LPUART_RX pin is disconnected from the LPUART and the transmitter output is
internally connected to the receiver input. The transmitter and the receiver must be enabled to use the
loop function.
0
Normal operation - LPUART_RX and LPUART_TX use separate pins.
1
Loop mode or single-wire mode where transmitter outputs are internally connected to receiver input
(see RSRC bit).
6
DOZEEN
Doze Enable
0
LPUART is enabled in Doze mode.
1
LPUART is disabled in Doze mode.
5
RSRC
Receiver Source Select
This field has no meaning or effect unless the LOOPS field is set. When LOOPS is set, the RSRC field
determines the source for the receiver shift register input.
0
Provided LOOPS is set, RSRC is cleared, selects internal loop back mode and the LPUART does not
use the LPUART_RX pin.
1
Single-wire LPUART mode where the LPUART_TX pin is connected to the transmitter output and
receiver input.
4
M
9-Bit or 8-Bit Mode Select
0
Receiver and transmitter use 8-bit data characters.
1
Receiver and transmitter use 9-bit data characters.
3
WAKE
Receiver Wakeup Method Select
Determines which condition wakes the LPUART when RWU=1:
• Address mark in the most significant bit position of a received data character, or
• An idle condition on the receive pin input signal.
Table continues on the next page...
Register definition
K22F Sub-Family Reference Manual , Rev. 3, 7/2014
1230
Freescale Semiconductor, Inc.