RM0440 Rev 4 1723/2126
RM0440 Low-power universal asynchronous receiver transmitter (LPUART)
1733
Bit 19 RWU: Receiver wakeup from Mute mode
This bit indicates if the LPUART is in Mute mode. It is cleared/set by hardware when a
wakeup/mute sequence is recognized. The Mute mode control sequence (address or IDLE)
is selected by the WAKE bit in the LPUART_CR1 register.
When wakeup on IDLE mode is selected, this bit can only be set by software, writing 1 to the
MMRQ bit in the LPUART_RQR register.
0: Receiver in Active mode
1: Receiver in Mute mode
Note: If the LPUART does not support the wakeup from Stop feature, this bit is reserved and
kept at reset value.
Bit 18 SBKF: Send break flag
This bit indicates that a send break character was requested. It is set by software, by writing
1 to the SBKRQ bit in the LPUART_CR3 register. It is automatically reset by hardware
during the stop bit of break transmission.
0: No break character transmitted
1: Break character transmitted
Bit 17 CMF: Character match flag
This bit is set by hardware, when a the character defined by ADD[7:0] is received. It is
cleared by software, writing 1 to the CMCF in the LPUART_ICR register.
An interrupt is generated if CMIE=1in the LPUART_CR1 register.
0: No Character match detected
1: Character Match detected
Bit 16 BUSY: Busy flag
This bit is set and reset by hardware. It is active when a communication is ongoing on the
RX line (successful start bit detected). It is reset at the end of the reception (successful or
not).
0: LPUART is idle (no reception)
1: Reception on going
Bits 15:11 Reserved, must be kept at reset value.
Bit 10 CTS: CTS flag
This bit is set/reset by hardware. It is an inverted copy of the status of the nCTS input pin.
0: nCTS line set
1: nCTS line reset
Note: If the hardware flow control feature is not supported, this bit is reserved and kept at
reset value.
Bit 9 CTSIF: CTS interrupt flag
This bit is set by hardware when the nCTS input toggles, if the CTSE bit is set. It is cleared
by software, by writing 1 to the CTSCF bit in the LPUART_ICR register.
An interrupt is generated if CTSIE=1 in the LPUART_CR3 register.
0: No change occurred on the nCTS status line
1: A change occurred on the nCTS status line
Note: If the hardware flow control feature is not supported, this bit is reserved and kept at
reset value.
Bit 8 Reserved, must be kept at reset value.
To Next Page
Loading...
Need help?
General
