
RM0453 Rev 2
RM0453
Low-power universal asynchronous receiver transmitter (LPUART)
1257
36.7 LPUART
registers
for a list of abbreviations used in register descriptions.
The peripheral registers have to be accessed by words (32 bits).
36.7.1
LPUART control register 1 [alternate] (LPUART_CR1)
Address offset: 0x00
Reset value: 0x0000 0000
The same register can be used in FIFO mode enabled (this section) and FIFO mode
disabled (next section).
FIFO mode enabled
1. The LPUART can wake up the device from Stop mode only if the peripheral instance supports the Wakeup from Stop mode
feature. Refer to
Section 36.3: LPUART implementation
for the list of supported Stop modes.
2. RXFF flag is asserted if the LPUART receives n+1 data (n being the RXFIFO size): n data in the RXFIFO and 1 data in
LPUART_RDR. In Stop mode, LPUART_RDR is not clocked. As a result, this register is not written and once n data are
received and written in the RXFIFO, the RXFF interrupt is asserted (RXFF flag is not set).
3. When OVRDIS = 0.
31
30
29
28
27
26
25
24
23
22
21
20
19
18
17
16
RXF
FIE
TXFEIE
FIFO
EN
M1
Res.
Res.
DEAT[4:0]
DEDT[4:0]
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15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
Res.
CMIE
MME
M0
WAKE
PCE
PS
PEIE
TXFN
FIE
TCIE
RXFN
EIE
IDLEIE
TE
RE
UESM
UE
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Bit 31
RXFFIE:
RXFIFO Full interrupt enable
This bit is set and cleared by software.
0: Interrupt is inhibited
1: An LPUART interrupt is generated when RXFF = 1 in the LPUART_ISR register
Bit 30
TXFEIE:
TXFIFO empty interrupt enable
This bit is set and cleared by software.
0: Interrupt is inhibited
1: An LPUART interrupt is generated when TXFE = 1 in the LPUART_ISR register
Bit 29
FIFOEN:
FIFO mode enable
This bit is set and cleared by software.
0: FIFO mode is disabled.
1: FIFO mode is enabled.