Renesas H8SX/1650, Руководство по оборудованию

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Section 13 Serial Communication Interface (SCI)
Rev.2.00 Jun. 28, 2007 Page 467 of 666
REJ09B0311-0200
Bit Bit Name
Initial
Value R/W Description
6 RDRF 0 R/(W) * Receive Data Register Full
Indicates whether receive data is stored in RDR.
[Setting condition]
•
When serial reception ends normally and receive
data is transferred from RSR to RDR
[Clearing conditions]
•
When 0 is written to RDRF after reading RDRF = 1
(When the CPU is used to clear this flag by writing 0
while the corresponding interrupt is enabled, be
sure to read the flag after writing 0 to it.)
•
When an RXI interrupt request is issued allowing
DTC to read data from RDR
The RDRF flag is not affected and retains its previous
value even when the RE bit in SCR is cleared to 0.
Note that when the next reception is completed while
the RDRF flag is being set to 1, an overrun error occurs
and the received data is lost.
5 ORER 0 R/(W) * Overrun Error
Indicates that an overrun error has occurred during
reception and the reception ends abnormally.
[Setting condition]
•
When the next serial reception is completed while
RDRF = 1
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. Note that, in clocked
synchronous mode, serial transmission also cannot
continue.
[Clearing condition]
•
When 0 is written to ORER after reading ORER = 1
(When the CPU is used to clear this flag by writing 0
while the corresponding interrupt is enabled, be
sure to read the flag after writing 0 to it.)
Even when the RE bit in SCR is cleared, the ORER
flag is not affected and retains its previous value.