Datasheet

Table Of Contents
DS13105 Rev 4 45/135
STM32WLE5J8/JB/JC Functional overview
46
The LPUART has a clock domain independent from the CPU clock, and can wake up the
system from Stop mode using baudrates up to 220 Kbaud. The wakeup events from Stop
mode are programmable and can be one of the following:
start bit detection
any received data frame
a specific programmed data frame
Only a 32.768 kHz clock (LSE) is needed to allow LPUART communication up to
9600 baud. Therefore, even in Stop mode, the LPUART can wait for an incoming frame
while having an extremely low-energy consumption. Higher speed clock can be used to
reach higher baudrates.
The LPUART interface can be served by the DMA controller.
3.28 Serial peripheral interface (SPI)/integrated-interchip sound
interface (I2S)
The SPI/I2S interface can be used to communicate with external devices using the SPI
protocol or the I
2
S audio protocol. SPI or I2S mode is selectable by software. SPI Motorola
®
mode is selected by default after a device reset.
The SPI protocol supports half-duplex, full-duplex and simplex synchronous, serial
communication with external devices. The SPI interface can be configured as master and, in
Table 16. USART/LPUART features
USART modes/features
(1)
1. X = supported.
USART1/2 LPUART1
Hardware flow control for modem X X
Continuous communication using DMA X X
Multiprocessor communication X X
Synchronous mode (Master/Slave) X -
Smartcard mode X -
Single-wire half-duplex communication X X
IrDA SIR ENDEC block X -
LIN mode X -
Dual clock domain and wakeup from low-power mode X X
Receiver timeout interrupt X -
Modbus communication X -
Auto baud rate detection X -
Driver enable X X
USART data length 7, 8 and 9 bits
Tx/Rx FIFO X X
Tx/Rx FIFO size 8