Datasheet

Section 17 Serial Communications Interface 3 (SCI3, IrDA)
Rev. 2.00 Jul. 04, 2007 Page 394 of 692
REJ09B0309-0200
Reception cannot be resumed while a receive error flag is set to 1. Accordingly, clear the OER,
FER, PER, and RDRF bits to 0 before resuming reception. Figure 17.13 shows a sample flowchart
for serial data reception.
Yes
<End>
No
Start reception
[1]
[4]
No
Yes
Read RDRF flag in SSR [2]
[3]
Clear RE bit in SCR to 0
Overrun error processing
(Continued below)
Read receive data in RDR
Yes
No
OER = 1?
RDRF = 1?
Data reception continued?
Read OER flag in SSR
Start overrun error processing
Overrun error processing
Clear OER flag in SSR to 0
[4]
[1] Read the OER flag in SSR to determine if
there is an error. If an overrun error has
occurred, execute overrun error processing.
[2] Read SSR and check that the RDRF flag is
set to 1, then read the receive data in RDR.
When data is read from RDR, the RDRF
flag is automatically cleared to 0.
[3] To continue serial reception, before the
MSB (bit 7) of the current frame is received,
reading the RDRF flag and reading RDR
should be finished. When data is read from
RDR, the RDRF flag is automatically
cleared to 0.
[4] If an overrun error occurs, read the OER
flag in SSR, and after performing the
appropriate error processing, clear the OER
flag to 0. Reception cannot be resumed if
the OER flag is set to 1.
End
Figure 17.13 Sample Serial Reception Flowchart (Clock Synchronous Mode)