Fujitsu F2MC-16LX Hardware Manual page 521

Synchronous type
Either asynchronous method or (start-stop synchronization) clock synchronous method can be selected.
Signal type
Data in NRZ (Non Return to Zero) format is only supported.
Start of transmission/reception
When the bit indicating that sending operation is enabled (SCR0 to SCR3: TXE) is set to "1", sending
operation starts.
Receiving operation starts when the reception enable bit of the serial control register (SCR0 to SCR3:RXE)
is set to "1".
Stop of transmission/reception
Transmission stops when the transmission enable bit (SCR0 to SCR3:TXE) in the serial control register is
set to "0".
Reception stops when the reception enable bit (SCR0 to SCR3:RXE) in the serial control register is set to
"0".
Stop during transmission/reception
When receiving operation (SCR0 to SCR3: RXE=0) is disabled in the middle of reception (while data is
being input to the receiving shift register), the receiving operation is halted after the frame that is being
received has completely received and the received data has been stored into the serial input data registers 0
to 3 (SIDR0 to SIDR3).
When sending operation (SCR0 to SCR3: TXE=0) is disabled in the middle of transmission (while data is
being output from the sending shift register), the sending operation is halted after one frame has been
completely sent.
CHAPTER 21 UART
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