ST STM32F101 series Reference Manual page 815

Universal synchronous asynchronous receiver transmitter (USART)
Bit 6 TCIE: Transmission complete interrupt enable
Bit 5 RXNEIE: RXNE interrupt enable
Bit 4 IDLEIE: IDLE interrupt enable
Bit 3 TE: Transmitter enable
Note: 1: During transmission, a "0" pulse on the TE bit ("0" followed by "1") sends a preamble
Bit 2 RE: Receiver enable
Bit 1 RWU: Receiver wakeup
Note: 1: Before selecting Mute mode (by setting the RWU bit) the USART must first receive a
Bit 0 SBK: Send break
815/1128
This bit is set and cleared by software.
0: Interrupt is inhibited
1: A USART interrupt is generated whenever TC=1 in the USART_SR register
This bit is set and cleared by software.
0: Interrupt is inhibited
1: A USART interrupt is generated whenever ORE=1 or RXNE=1 in the USART_SR register
This bit is set and cleared by software.
0: Interrupt is inhibited
1: A USART interrupt is generated whenever IDLE=1 in the USART_SR register
This bit enables the transmitter. It is set and cleared by software.
0: Transmitter is disabled
1: Transmitter is enabled
(idle line) after the current word, except in smartcard mode.
2: When TE is set there is a 1 bit-time delay before the transmission starts.
This bit enables the receiver. It is set and cleared by software.
0: Receiver is disabled
1: Receiver is enabled and begins searching for a start bit
This bit determines if the USART is in mute mode or not. It is set and cleared by software and
can be cleared by hardware when a wakeup sequence is recognized.
0: Receiver in active mode
1: Receiver in mute mode
data byte, otherwise it cannot function in Mute mode with wakeup by Idle line detection.
2: In Address Mark Detection wakeup configuration (WAKE bit=1) the RWU bit cannot
be modified by software while the RXNE bit is set.
This bit set is used to send break characters. It can be set and cleared by software. It should
be set by software, and will be reset by hardware during the stop bit of break.
0: No break character is transmitted
1: Break character will be transmitted
DocID13902 Rev 15
RM0008