R01UH0823EJ0100 Rev.1.00
Page 985 of 1823
Jul 31, 2019
RX23W Group
33. Serial Communications Interface (SCIg, SCIh)
Indicates that a parity error has occurred during reception in asynchronous mode and the reception ends abnormally.
[Setting condition]
When a parity error is detected during reception
Although receive data when the parity error occurs is transferred to RDR, no RXI interrupt request occurs. Note that
when the PER flag is being set to 1, the subsequent receive data is not transferred to RDR.
[Clearing condition]
When 0 is written to PER after reading PER = 1
When setting the PER flag to 0 to complete the interrupt handling, refer to
section 15.4.1.2, Operation of Status
Flags for Level-Detected Interrupts
.
Even when the SCR.RE bit is set to 0 (serial reception is disabled), the PER flag is not affected and retains its
previous value.
ERS Flag (Error Signal Status Flag)
[Setting condition]
When a low error signal is sampled
[Clearing condition]
When 0 is written to ERS after reading ERS = 1
When setting the ERS flag to 0 to complete the interrupt handling, refer to
section 15.4.1.2, Operation of Status
Flags for Level-Detected Interrupts
.
Even when the SCR.RE bit is set to 0, the ERS flag is not affected and retains its previous value.
ORER Flag (Overrun Error Flag)
Indicates that an overrun error has occurred during reception and the reception ends abnormally.
[Setting condition]
When the next data is received before receive data is read from RDR
In RDR, the receive data prior to an overrun error occurrence is retained, but data received following the overrun
error occurrence is lost. When the ORER flag is set to 1, subsequent serial reception cannot be performed.
[Clearing condition]
When 0 is written to ORER after reading ORER = 1
When setting the ORER flag to 0 to complete the interrupt handling, refer to
section 15.4.1.2, Operation of
Status Flags for Level-Detected Interrupts
Even when the SCR.RE bit is set to 0, the ORER flag is not affected and retains its previous value.
RDRF Flag (Receive Data Full Flag)
Indicates whether the RDR register has received data.
[Setting condition]
When data has been received normally, and transferred from RSR to RDR
[Clearing condition]
When data is read from RDR
TDRE Flag (Transmit Data Empty Flag)
Indicates whether the TDR register has data to be transmitted.
[Setting condition]
When data is transferred from TDR to TSR
[Clearing condition]
When data is written to TDR