426
Bit 5—Overrun Error (ORER):
Indicates that an overrun error occurred during reception,
causing abnormal termination.
Bit 5
ORER
Description
0
[Clearing condition]
When 0 is written to ORER after reading ORER = 1
(Initial value)
*
1
1
[Setting condition]
When the next serial reception is completed while RDRF = 1
Notes: 1. The ORER flag is not affected and retains its previous state when the RE bit in SCR is
cleared to 0.
2. The receive data prior to the overrun error is retained in RDR, and the data received
subsequently is lost. Also, subsequent serial reception cannot be continued while the
ORER flag is set to 1. In clocked synchronous mode, serial transmission cannot be
continued, either.
Bit 4—Framing Error (FER):
Indicates that a framing error occurred during reception in
asynchronous mode, causing abnormal termination.
Bit 4
FER
Description
0
[Clearing condition]
(Initial value)
*
1
When 0 is written to FER after reading FER = 1
[Setting condition]
When the SCI checks whether the stop bit at the end of the receive data when
reception ends, and the stop bit is 0
*
2
Notes: 1. The FER flag is not affected and retains its previous state when the RE bit in SCR is
cleared to 0.
2. In 2-stop-bit mode, only the first stop bit is checked for a value of 0; the second stop bit
is not checked. If a framing error occurs, the receive data is transferred to RDR but the
RDRF flag is not set. Also, subsequent serial reception cannot be continued while the
FER flag is set to 1. In clocked synchronous mode, serial transmission cannot be
continued, either.
1