Datasheet

Section 12 Serial Communication Interface (SCI)
Rev.7.00 Feb. 14, 2007 page 487 of 1108
REJ09B0089-0700
Yes
<End>
[1]
No
Initialization
Start of reception
[2]
No
Yes
Read RDRF flag in SSR [4]
[5]
Clear RE bit in SCR to 0
Error processing
(Continued below)
[3]
Read receive data in RDR, and
clear RDRF flag in SSR to 0
No
Yes
ORER = 1?
RDRF = 1?
All data received?
Read ORER flag in SSR
[1]
[2] [3]
[4]
[5]
SCI initialization:
The RxD pin is automatically
designated as the receive data
input pin.
Receive error handling:
If a receive error occurs, read the
ORER flag in SSR,
and after
performing the appropriate error
handling, clear the ORER flag to
0. Transfer cannot be resumed if
the ORER flag is set to 1.
SCI status check and receive
data read:
Read SSR and check that the
RDRF flag i
s set to 1, then read
the receive data in RDR and
clear the RDRF flag to 0.
Transition of the RDRF flag from
0 to 1 can also be identified by
an RXI interrupt.
Serial reception continuation
procedure:
To continue serial reception,
before the MSB (bit 7) of the
current frame is received, finish
reading the RDRF flag, reading
RDR, and clearing the RDRF flag
to 0. The RDRF flag is
cleared
automatically when the DTC is
activated by a receive-data-full
interrupt (RXI) request and the
RDR value is read.
<End>
Error handling
Overrun error handling
[3]
Clear ORER flag in SSR to 0
Figure 12.18 Sample Serial Reception Flowchart