Signal
Description
I/O
LPUART_RX
Receive data.
I
LPUART_CTS
Clear to send.
I
LPUART_RTS
Request to send.
O
47.1.4 Block diagram
The following figure shows the transmitter portion of the LPUART.
H 8
7
6
5
4
3
2
1
0
L
LPUART_D – Tx Buffer
(Write-Only)
Internal Bus
S
to
p
11-BIT Transmit Shift Register
S
ta
rt
SHIFT DIRECTION
ls
b
Parity
Generation
Transmit Control
S
hif
t E
na
bl
e
Prea
mb
le
(All
1
s)
B
re
ak
(
A
ll
0s
)
LPUART Controls TxD
TxD Direction
TO TxD
Pin Logic
Loop
Control
To Receive
Data In
To TxD Pin
Tx Interrupt
Request
LOOPS
RSRC
TIE
TC
TDRE
M
PT
PE
TCIE
TE
SBK
T8
TXDIR
Load From LPUARTx_D
TXINV
BRK13
ASYNCH
MODULE
CLOCK
BAUD
Divider
OSR
Divider
Figure 47-1. LPUART transmitter block diagram
The following figure shows the receiver portion of the LPUART.
Chapter 47 Low Power Universal asynchronous receiver/transmitter (LPUART)
K22F Sub-Family Reference Manual , Rev. 3, 7/2014
Freescale Semiconductor, Inc.
1219